applies new string literal convention in railties/test

The current code base is not uniform. After some discussion,
we have chosen to go with double quotes by default.

95 files changed, 1595 insertions, 1595 deletions

diff --git a/railties/test/abstract_unit.rb b/railties/test/abstract_unit.rb
index 2a5a731fe2..fd1e1b9662 100644
--- a/railties/test/abstract_unit.rb
+++ b/railties/test/abstract_unit.rb
@@ -1,28 +1,28 @@
 ENV["RAILS_ENV"] ||= "test"
 
-require 'stringio'
-require 'active_support/testing/autorun'
-require 'active_support/testing/stream'
-require 'fileutils'
+require "stringio"
+require "active_support/testing/autorun"
+require "active_support/testing/stream"
+require "fileutils"
 
-require 'active_support'
-require 'action_controller'
-require 'action_view'
-require 'rails/all'
+require "active_support"
+require "action_controller"
+require "action_view"
+require "rails/all"
 
 module TestApp
   class Application < Rails::Application
     config.root = File.dirname(__FILE__)
-    secrets.secret_key_base = 'b3c631c314c0bbca50c1b2843150fe33'
+    secrets.secret_key_base = "b3c631c314c0bbca50c1b2843150fe33"
   end
 end
 
 # Skips the current run on Rubinius using Minitest::Assertions#skip
-def rubinius_skip(message = '')
-  skip message if RUBY_ENGINE == 'rbx'
+def rubinius_skip(message = "")
+  skip message if RUBY_ENGINE == "rbx"
 end
 # Skips the current run on JRuby using Minitest::Assertions#skip
-def jruby_skip(message = '')
+def jruby_skip(message = "")
   skip message if defined?(JRUBY_VERSION)
 end
 
diff --git a/railties/test/app_loader_test.rb b/railties/test/app_loader_test.rb
index 5946c8fd4c..7fd5c72c1c 100644
--- a/railties/test/app_loader_test.rb
+++ b/railties/test/app_loader_test.rb
@@ -1,6 +1,6 @@
-require 'tmpdir'
-require 'abstract_unit'
-require 'rails/app_loader'
+require "tmpdir"
+require "abstract_unit"
+require "rails/app_loader"
 
 class AppLoaderTest < ActiveSupport::TestCase
   def loader
@@ -27,12 +27,12 @@ class AppLoaderTest < ActiveSupport::TestCase
   end
 
   setup do
-    @tmp = Dir.mktmpdir('railties-rails-loader-test-suite')
+    @tmp = Dir.mktmpdir("railties-rails-loader-test-suite")
     @cwd = Dir.pwd
     Dir.chdir(@tmp)
   end
 
-  ['bin', 'script'].each do |script_dir|
+  ["bin", "script"].each do |script_dir|
     exe = "#{script_dir}/rails"
 
     test "is not in a Rails application if #{exe} is not found in the current or parent directories" do
@@ -47,7 +47,7 @@ class AppLoaderTest < ActiveSupport::TestCase
       assert !loader.exec_app
     end
 
-    ['APP_PATH', 'ENGINE_PATH'].each do |keyword|
+    ["APP_PATH", "ENGINE_PATH"].each do |keyword|
       test "is in a Rails application if #{exe} exists and contains #{keyword}" do
         write exe, keyword
 
@@ -66,7 +66,7 @@ class AppLoaderTest < ActiveSupport::TestCase
         write "foo/bar/#{exe}"
         write "foo/#{exe}", keyword
 
-        Dir.chdir('foo/bar')
+        Dir.chdir("foo/bar")
 
         loader.exec_app
 
diff --git a/railties/test/application/asset_debugging_test.rb b/railties/test/application/asset_debugging_test.rb
index 19327efcc8..ccecf2c09e 100644
--- a/railties/test/application/asset_debugging_test.rb
+++ b/railties/test/application/asset_debugging_test.rb
@@ -1,5 +1,5 @@
-require 'isolation/abstract_unit'
-require 'rack/test'
+require "isolation/abstract_unit"
+require "rack/test"
 
 module ApplicationTests
   class AssetDebuggingTest < ActiveSupport::TestCase
@@ -51,7 +51,7 @@ module ApplicationTests
       class ::PostsController < ActionController::Base ; end
 
       # the debug_assets params isn't used if compile is off
-      get '/posts?debug_assets=true'
+      get "/posts?debug_assets=true"
       assert_match(/<script src="\/assets\/application-([0-z]+)\.js"><\/script>/, last_response.body)
       assert_no_match(/<script src="\/assets\/xmlhr-([0-z]+)\.js"><\/script>/, last_response.body)
     end
@@ -64,7 +64,7 @@ module ApplicationTests
 
       class ::PostsController < ActionController::Base ; end
 
-      get '/posts?debug_assets=true'
+      get "/posts?debug_assets=true"
       assert_match(/<script src="\/assets\/application(\.self)?-([0-z]+)\.js\?body=1"><\/script>/, last_response.body)
       assert_match(/<script src="\/assets\/xmlhr(\.self)?-([0-z]+)\.js\?body=1"><\/script>/, last_response.body)
     end
diff --git a/railties/test/application/assets_test.rb b/railties/test/application/assets_test.rb
index 20329c6e60..3b5bf7ce87 100644
--- a/railties/test/application/assets_test.rb
+++ b/railties/test/application/assets_test.rb
@@ -1,6 +1,6 @@
-require 'isolation/abstract_unit'
-require 'rack/test'
-require 'active_support/json'
+require "isolation/abstract_unit"
+require "rack/test"
+require "active_support/json"
 
 module ApplicationTests
   class AssetsTest < ActiveSupport::TestCase
@@ -35,7 +35,7 @@ module ApplicationTests
 
     def clean_assets!
       quietly do
-        assert Dir.chdir(app_path) { system('bin/rails assets:clobber') }
+        assert Dir.chdir(app_path) { system("bin/rails assets:clobber") }
       end
     end
 
@@ -52,7 +52,7 @@ module ApplicationTests
       app_file "app/assets/images/rails.png", "notactuallyapng"
       app_file "app/assets/javascripts/demo.js.erb", "a = <%= image_path('rails.png').inspect %>;"
 
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get '*path', to: lambda { |env| [200, { "Content-Type" => "text/html" }, ["Not an asset"]] }
         end
@@ -110,8 +110,8 @@ module ApplicationTests
       eoruby
 
       precompile! \
-        RAILS_ENV: 'production',
-        DATABASE_URL: 'postgresql://baduser:badpass@127.0.0.1/dbname'
+        RAILS_ENV: "production",
+        DATABASE_URL: "postgresql://baduser:badpass@127.0.0.1/dbname"
 
       files = Dir["#{app_path}/public/assets/application-*.js"]
       files << Dir["#{app_path}/public/assets/foo/application-*.js"].first
@@ -176,19 +176,19 @@ module ApplicationTests
       assert_file_exists("#{app_path}/public/assets/something/index-*.js")
     end
 
-    test 'precompile use assets defined in app env config' do
-      add_to_env_config 'production', 'config.assets.precompile = [ "something.js" ]'
-      app_file 'app/assets/javascripts/something.js.erb', 'alert();'
+    test "precompile use assets defined in app env config" do
+      add_to_env_config "production", 'config.assets.precompile = [ "something.js" ]'
+      app_file "app/assets/javascripts/something.js.erb", "alert();"
 
-      precompile! RAILS_ENV: 'production'
+      precompile! RAILS_ENV: "production"
 
       assert_file_exists("#{app_path}/public/assets/something-*.js")
     end
 
-    test 'sprockets cache is not shared between environments' do
+    test "sprockets cache is not shared between environments" do
       app_file "app/assets/images/rails.png", "notactuallyapng"
       app_file "app/assets/stylesheets/application.css.erb", "body { background: '<%= asset_path('rails.png') %>'; }"
-      add_to_env_config 'production', 'config.assets.prefix = "production_assets"'
+      add_to_env_config "production", 'config.assets.prefix = "production_assets"'
 
       precompile!
 
@@ -197,7 +197,7 @@ module ApplicationTests
       file = Dir["#{app_path}/public/assets/application-*.css"].first
       assert_match(/assets\/rails-([0-z]+)\.png/, File.read(file))
 
-      precompile! RAILS_ENV: 'production'
+      precompile! RAILS_ENV: "production"
 
       assert_file_exists("#{app_path}/public/production_assets/application-*.css")
 
@@ -205,17 +205,17 @@ module ApplicationTests
       assert_match(/production_assets\/rails-([0-z]+)\.png/, File.read(file))
     end
 
-    test 'precompile use assets defined in app config and reassigned in app env config' do
+    test "precompile use assets defined in app config and reassigned in app env config" do
       add_to_config 'config.assets.precompile = [ "something_manifest.js" ]'
-      add_to_env_config 'production', 'config.assets.precompile += [ "another_manifest.js" ]'
+      add_to_env_config "production", 'config.assets.precompile += [ "another_manifest.js" ]'
 
-      app_file 'app/assets/config/something_manifest.js', '//= link something.js'
-      app_file 'app/assets/config/another_manifest.js', '//= link another.js'
+      app_file "app/assets/config/something_manifest.js", "//= link something.js"
+      app_file "app/assets/config/another_manifest.js", "//= link another.js"
 
-      app_file 'app/assets/javascripts/something.js.erb', 'alert();'
-      app_file 'app/assets/javascripts/another.js.erb', 'alert();'
+      app_file "app/assets/javascripts/something.js.erb", "alert();"
+      app_file "app/assets/javascripts/another.js.erb", "alert();"
 
-      precompile! RAILS_ENV: 'production'
+      precompile! RAILS_ENV: "production"
 
       assert_file_exists("#{app_path}/public/assets/something_manifest-*.js")
       assert_file_exists("#{app_path}/public/assets/something-*.js")
@@ -261,7 +261,7 @@ module ApplicationTests
       app_file "app/assets/javascripts/application.js", "alert();"
       add_to_env_config "production", "config.public_file_server.enabled = true"
 
-      precompile! RAILS_ENV: 'production'
+      precompile! RAILS_ENV: "production"
 
       manifest = Dir["#{app_path}/public/assets/.sprockets-manifest-*.json"].first
       assets = ActiveSupport::JSON.decode(File.read(manifest))
@@ -292,7 +292,7 @@ module ApplicationTests
 
       app_file "app/assets/stylesheets/application.css.erb", "p { background-image: url(<%= asset_path('rails.png') %>) }"
 
-      precompile! RAILS_ENV: 'production'
+      precompile! RAILS_ENV: "production"
 
       manifest = Dir["#{app_path}/public/assets/.sprockets-manifest-*.json"].first
       assets = ActiveSupport::JSON.decode(File.read(manifest))
@@ -310,7 +310,7 @@ module ApplicationTests
       app_file "app/assets/images/rails.png", "notactuallyapng"
       app_file "app/assets/stylesheets/application.css.erb", "p { background-image: url(<%= asset_path('rails.png') %>) }"
 
-      precompile! RAILS_ENV: 'production'
+      precompile! RAILS_ENV: "production"
 
       file = Dir["#{app_path}/public/assets/application-*.css"].first
       assert_match(/\/assets\/rails-([0-z]+)\.png/, File.read(file))
@@ -380,7 +380,7 @@ module ApplicationTests
       end
 
       get "/omg"
-      assert_equal 'ok', last_response.body
+      assert_equal "ok", last_response.body
 
       get "/assets/demo.js"
       assert_match "alert()", last_response.body
@@ -408,7 +408,7 @@ module ApplicationTests
       app_with_assets_in_view
 
       # config.assets.debug and config.assets.compile are false for production environment
-      precompile! RAILS_ENV: 'production'
+      precompile! RAILS_ENV: "production"
 
       # Load app env
       app "production"
@@ -416,7 +416,7 @@ module ApplicationTests
       class ::PostsController < ActionController::Base ; end
 
       # the debug_assets params isn't used if compile is off
-      get '/posts?debug_assets=true'
+      get "/posts?debug_assets=true"
       assert_match(/<script src="\/assets\/application-([0-z]+)\.js"><\/script>/, last_response.body)
       assert_no_match(/<script src="\/assets\/xmlhr-([0-z]+)\.js"><\/script>/, last_response.body)
     end
@@ -475,9 +475,9 @@ module ApplicationTests
 
       class ::PostsController < ActionController::Base; end
 
-      get '/posts', {}, {'HTTPS'=>'off'}
+      get "/posts", {}, {"HTTPS"=>"off"}
       assert_match('src="http://example.com/assets/application.self.js', last_response.body)
-      get '/posts', {}, {'HTTPS'=>'on'}
+      get "/posts", {}, {"HTTPS"=>"on"}
       assert_match('src="https://example.com/assets/application.self.js', last_response.body)
     end
 
diff --git a/railties/test/application/bin_setup_test.rb b/railties/test/application/bin_setup_test.rb
index ba700df1d6..2f076ea2f6 100644
--- a/railties/test/application/bin_setup_test.rb
+++ b/railties/test/application/bin_setup_test.rb
@@ -1,4 +1,4 @@
-require 'isolation/abstract_unit'
+require "isolation/abstract_unit"
 
 module ApplicationTests
   class BinSetupTest < ActiveSupport::TestCase
@@ -14,7 +14,7 @@ module ApplicationTests
 
     def test_bin_setup
       Dir.chdir(app_path) do
-        app_file 'db/schema.rb', <<-RUBY
+        app_file "db/schema.rb", <<-RUBY
           ActiveRecord::Schema.define(version: 20140423102712) do
             create_table(:articles) {}
           end
@@ -23,7 +23,7 @@ module ApplicationTests
         list_tables = lambda { `bin/rails runner 'p ActiveRecord::Base.connection.tables'`.strip }
         File.write("log/test.log", "zomg!")
 
-        assert_equal '[]', list_tables.call
+        assert_equal "[]", list_tables.call
         assert_equal 5, File.size("log/test.log")
         assert_not File.exist?("tmp/restart.txt")
         `bin/setup 2>&1`
@@ -35,7 +35,7 @@ module ApplicationTests
 
     def test_bin_setup_output
       Dir.chdir(app_path) do
-        app_file 'db/schema.rb', ""
+        app_file "db/schema.rb", ""
 
         output = `bin/setup 2>&1`
         assert_equal(<<-OUTPUT, output)
diff --git a/railties/test/application/configuration/custom_test.rb b/railties/test/application/configuration/custom_test.rb
index 677cb8328c..13fc98f0d6 100644
--- a/railties/test/application/configuration/custom_test.rb
+++ b/railties/test/application/configuration/custom_test.rb
@@ -1,4 +1,4 @@
-require 'isolation/abstract_unit'
+require "isolation/abstract_unit"
 
 module ApplicationTests
   module ConfigurationTests
@@ -13,7 +13,7 @@ module ApplicationTests
         FileUtils.rm_rf(new_app) if File.directory?(new_app)
       end
 
-      test 'access custom configuration point' do
+      test "access custom configuration point" do
         add_to_config <<-RUBY
           config.x.payment_processing.schedule = :daily
           config.x.payment_processing.retries  = 3
@@ -32,7 +32,7 @@ module ApplicationTests
         assert_nil x.i_do_not_exist.zomg
       end
 
-      test 'custom configuration responds to all messages' do
+      test "custom configuration responds to all messages" do
         x = Rails.configuration.x
         assert_equal true, x.respond_to?(:i_do_not_exist)
         assert_kind_of Method, x.method(:i_do_not_exist)
diff --git a/railties/test/application/configuration_test.rb b/railties/test/application/configuration_test.rb
index e4a3adee9f..01bdcfb9aa 100644
--- a/railties/test/application/configuration_test.rb
+++ b/railties/test/application/configuration_test.rb
@@ -1,6 +1,6 @@
 require "isolation/abstract_unit"
-require 'rack/test'
-require 'env_helpers'
+require "rack/test"
+require "env_helpers"
 
 class ::MyMailInterceptor
   def self.delivering_email(email); email; end
@@ -34,9 +34,9 @@ module ApplicationTests
       FileUtils.cp_r(app_path, new_app)
     end
 
-    def app(env = 'development')
+    def app(env = "development")
       @app ||= begin
-        ENV['RAILS_ENV'] = env
+        ENV["RAILS_ENV"] = env
 
         # FIXME: shush Sass warning spam, not relevant to testing Railties
         Kernel.silence_warnings do
@@ -45,7 +45,7 @@ module ApplicationTests
 
         Rails.application
       ensure
-        ENV.delete 'RAILS_ENV'
+        ENV.delete "RAILS_ENV"
       end
     end
 
@@ -74,7 +74,7 @@ module ApplicationTests
       switch_env "RAILS_ENV", nil do
         Rails.env = "development"
         assert_equal "development", Rails.env
-        assert_nil ENV['RAILS_ENV']
+        assert_nil ENV["RAILS_ENV"]
       end
     end
 
@@ -82,7 +82,7 @@ module ApplicationTests
       restore_default_config
 
       with_rails_env "development" do
-        app 'development'
+        app "development"
         assert Rails.application.config.log_tags.blank?
       end
     end
@@ -91,13 +91,13 @@ module ApplicationTests
       restore_default_config
 
       with_rails_env "production" do
-        app 'production'
+        app "production"
         assert_equal [:request_id], Rails.application.config.log_tags
       end
     end
 
     test "lib dir is on LOAD_PATH during config" do
-      app_file 'lib/my_logger.rb', <<-RUBY
+      app_file "lib/my_logger.rb", <<-RUBY
         require "logger"
         class MyLogger < ::Logger
         end
@@ -107,9 +107,9 @@ module ApplicationTests
         config.logger = MyLogger.new STDOUT
       RUBY
 
-      app 'development'
+      app "development"
 
-      assert_equal 'MyLogger', Rails.application.config.logger.class.name
+      assert_equal "MyLogger", Rails.application.config.logger.class.name
     end
 
     test "a renders exception on pending migration" do
@@ -119,7 +119,7 @@ module ApplicationTests
         config.action_dispatch.show_exceptions  = true
       RUBY
 
-      app_file 'db/migrate/20140708012246_create_user.rb', <<-RUBY
+      app_file "db/migrate/20140708012246_create_user.rb", <<-RUBY
         class CreateUser < ActiveRecord::Migration::Current
           def change
             create_table :users
@@ -127,7 +127,7 @@ module ApplicationTests
         end
       RUBY
 
-      app 'development'
+      app "development"
 
       ActiveRecord::Migrator.migrations_paths = ["#{app_path}/db/migrate"]
 
@@ -156,31 +156,31 @@ module ApplicationTests
     end
 
     test "Rails.application is nil until app is initialized" do
-      require 'rails'
+      require "rails"
       assert_nil Rails.application
-      app 'development'
+      app "development"
       assert_equal AppTemplate::Application.instance, Rails.application
     end
 
     test "Rails.application responds to all instance methods" do
-      app 'development'
+      app "development"
       assert_respond_to Rails.application, :routes_reloader
       assert_equal Rails.application.routes_reloader, AppTemplate::Application.routes_reloader
     end
 
     test "Rails::Application responds to paths" do
-      app 'development'
+      app "development"
       assert_respond_to AppTemplate::Application, :paths
       assert_equal ["#{app_path}/app/views"], AppTemplate::Application.paths["app/views"].expanded
     end
 
     test "the application root is set correctly" do
-      app 'development'
+      app "development"
       assert_equal Pathname.new(app_path), Rails.application.root
     end
 
     test "the application root can be seen from the application singleton" do
-      app 'development'
+      app "development"
       assert_equal Pathname.new(app_path), AppTemplate::Application.root
     end
 
@@ -192,7 +192,7 @@ module ApplicationTests
 
       use_frameworks []
 
-      app 'development'
+      app "development"
 
       assert_equal Pathname.new(new_app), Rails.application.root
     end
@@ -203,7 +203,7 @@ module ApplicationTests
       use_frameworks []
 
       Dir.chdir("#{app_path}") do
-        app 'development'
+        app "development"
         assert_equal Pathname.new("#{app_path}"), Rails.application.root
       end
     end
@@ -213,7 +213,7 @@ module ApplicationTests
         config.root = "#{app_path}"
       RUBY
 
-      app 'development'
+      app "development"
 
       assert_instance_of Pathname, Rails.root
     end
@@ -223,7 +223,7 @@ module ApplicationTests
         config.paths["public"] = "somewhere"
       RUBY
 
-      app 'development'
+      app "development"
 
       assert_instance_of Pathname, Rails.public_path
     end
@@ -234,13 +234,13 @@ module ApplicationTests
         config.cache_classes = true
       RUBY
 
-      app 'development'
+      app "development"
 
       assert_equal :require, ActiveSupport::Dependencies.mechanism
     end
 
     test "application is always added to eager_load namespaces" do
-      app 'development'
+      app "development"
       assert_includes Rails.application.config.eager_load_namespaces, AppTemplate::Application
     end
 
@@ -256,7 +256,7 @@ module ApplicationTests
       use_frameworks []
 
       assert_nothing_raised do
-        app 'development'
+        app "development"
       end
     end
 
@@ -268,18 +268,18 @@ module ApplicationTests
       RUBY
 
       assert_nothing_raised do
-        app 'development'
+        app "development"
       end
     end
 
     test "filter_parameters should be able to set via config.filter_parameters in an initializer" do
-      app_file 'config/initializers/filter_parameters_logging.rb', <<-RUBY
+      app_file "config/initializers/filter_parameters_logging.rb", <<-RUBY
         Rails.application.config.filter_parameters += [ :password, :foo, 'bar' ]
       RUBY
 
-      app 'development'
+      app "development"
 
-      assert_equal [:password, :foo, 'bar'], Rails.application.env_config['action_dispatch.parameter_filter']
+      assert_equal [:password, :foo, "bar"], Rails.application.env_config["action_dispatch.parameter_filter"]
     end
 
     test "config.to_prepare is forwarded to ActionDispatch" do
@@ -293,7 +293,7 @@ module ApplicationTests
 
       assert !$prepared
 
-      app 'development'
+      app "development"
 
       get "/"
       assert $prepared
@@ -305,7 +305,7 @@ module ApplicationTests
     end
 
     test "skipping config.encoding still results in 'utf-8' as the default" do
-      app 'development'
+      app "development"
       assert_utf8
     end
 
@@ -314,7 +314,7 @@ module ApplicationTests
         config.encoding = "utf-8"
       RUBY
 
-      app 'development'
+      app "development"
       assert_utf8
     end
 
@@ -323,7 +323,7 @@ module ApplicationTests
         config.paths["public"] = "somewhere"
       RUBY
 
-      app 'development'
+      app "development"
       assert_equal Pathname.new(app_path).join("somewhere"), Rails.public_path
     end
 
@@ -331,7 +331,7 @@ module ApplicationTests
       restore_default_config
 
       with_rails_env "production" do
-        app 'production'
+        app "production"
         assert_not app.config.public_file_server.enabled
       end
     end
@@ -341,7 +341,7 @@ module ApplicationTests
 
       with_rails_env "production" do
         switch_env "RAILS_SERVE_STATIC_FILES", "1" do
-          app 'production'
+          app "production"
           assert app.config.public_file_server.enabled
         end
       end
@@ -352,7 +352,7 @@ module ApplicationTests
 
       with_rails_env "production" do
         switch_env "RAILS_LOG_TO_STDOUT", "1" do
-          app 'production'
+          app "production"
           assert ActiveSupport::Logger.logger_outputs_to?(app.config.logger, STDOUT)
         end
       end
@@ -363,7 +363,7 @@ module ApplicationTests
 
       with_rails_env "production" do
         switch_env "RAILS_SERVE_STATIC_FILES", " " do
-          app 'production'
+          app "production"
           assert_not app.config.public_file_server.enabled
         end
       end
@@ -391,7 +391,7 @@ module ApplicationTests
 
     test "Use key_generator when secret_key_base is set" do
       make_basic_app do |application|
-        application.secrets.secret_key_base = 'b3c631c314c0bbca50c1b2843150fe33'
+        application.secrets.secret_key_base = "b3c631c314c0bbca50c1b2843150fe33"
         application.config.session_store :disabled
       end
 
@@ -404,53 +404,53 @@ module ApplicationTests
 
       get "/"
 
-      secret = app.key_generator.generate_key('signed cookie')
+      secret = app.key_generator.generate_key("signed cookie")
       verifier = ActiveSupport::MessageVerifier.new(secret)
-      assert_equal 'some_value', verifier.verify(last_response.body)
+      assert_equal "some_value", verifier.verify(last_response.body)
     end
 
     test "application verifier can be used in the entire application" do
       make_basic_app do |application|
-        application.secrets.secret_key_base = 'b3c631c314c0bbca50c1b2843150fe33'
+        application.secrets.secret_key_base = "b3c631c314c0bbca50c1b2843150fe33"
         application.config.session_store :disabled
       end
 
       message = app.message_verifier(:sensitive_value).generate("some_value")
 
-      assert_equal 'some_value', Rails.application.message_verifier(:sensitive_value).verify(message)
+      assert_equal "some_value", Rails.application.message_verifier(:sensitive_value).verify(message)
 
-      secret = app.key_generator.generate_key('sensitive_value')
+      secret = app.key_generator.generate_key("sensitive_value")
       verifier = ActiveSupport::MessageVerifier.new(secret)
-      assert_equal 'some_value', verifier.verify(message)
+      assert_equal "some_value", verifier.verify(message)
     end
 
     test "application message verifier can be used when the key_generator is ActiveSupport::LegacyKeyGenerator" do
-      app_file 'config/initializers/secret_token.rb', <<-RUBY
+      app_file "config/initializers/secret_token.rb", <<-RUBY
         Rails.application.config.secret_token = "b3c631c314c0bbca50c1b2843150fe33"
       RUBY
-      app_file 'config/secrets.yml', <<-YAML
+      app_file "config/secrets.yml", <<-YAML
         development:
           secret_key_base:
       YAML
 
-      app 'development'
+      app "development"
 
-      assert_equal app.env_config['action_dispatch.key_generator'], Rails.application.key_generator
-      assert_equal app.env_config['action_dispatch.key_generator'].class, ActiveSupport::LegacyKeyGenerator
+      assert_equal app.env_config["action_dispatch.key_generator"], Rails.application.key_generator
+      assert_equal app.env_config["action_dispatch.key_generator"].class, ActiveSupport::LegacyKeyGenerator
       message = app.message_verifier(:sensitive_value).generate("some_value")
-      assert_equal 'some_value', Rails.application.message_verifier(:sensitive_value).verify(message)
+      assert_equal "some_value", Rails.application.message_verifier(:sensitive_value).verify(message)
     end
 
     test "warns when secrets.secret_key_base is blank and config.secret_token is set" do
-      app_file 'config/initializers/secret_token.rb', <<-RUBY
+      app_file "config/initializers/secret_token.rb", <<-RUBY
         Rails.application.config.secret_token = "b3c631c314c0bbca50c1b2843150fe33"
       RUBY
-      app_file 'config/secrets.yml', <<-YAML
+      app_file "config/secrets.yml", <<-YAML
         development:
           secret_key_base:
       YAML
 
-      app 'development'
+      app "development"
 
       assert_deprecated(/You didn't set `secret_key_base`./) do
         app.env_config
@@ -458,12 +458,12 @@ module ApplicationTests
     end
 
     test "raise when secrets.secret_key_base is not a type of string" do
-      app_file 'config/secrets.yml', <<-YAML
+      app_file "config/secrets.yml", <<-YAML
         development:
           secret_key_base: 123
       YAML
 
-      app 'development'
+      app "development"
 
       assert_raise(ArgumentError) do
         app.key_generator
@@ -471,31 +471,31 @@ module ApplicationTests
     end
 
     test "prefer secrets.secret_token over config.secret_token" do
-      app_file 'config/initializers/secret_token.rb', <<-RUBY
+      app_file "config/initializers/secret_token.rb", <<-RUBY
         Rails.application.config.secret_token = ""
       RUBY
-      app_file 'config/secrets.yml', <<-YAML
+      app_file "config/secrets.yml", <<-YAML
         development:
           secret_token: 3b7cd727ee24e8444053437c36cc66c3
       YAML
 
-      app 'development'
+      app "development"
 
-      assert_equal '3b7cd727ee24e8444053437c36cc66c3', app.secrets.secret_token
+      assert_equal "3b7cd727ee24e8444053437c36cc66c3", app.secrets.secret_token
     end
 
     test "application verifier can build different verifiers" do
       make_basic_app do |application|
-        application.secrets.secret_key_base = 'b3c631c314c0bbca50c1b2843150fe33'
+        application.secrets.secret_key_base = "b3c631c314c0bbca50c1b2843150fe33"
         application.config.session_store :disabled
       end
 
       default_verifier = app.message_verifier(:sensitive_value)
       text_verifier = app.message_verifier(:text)
 
-      message = text_verifier.generate('some_value')
+      message = text_verifier.generate("some_value")
 
-      assert_equal 'some_value', text_verifier.verify(message)
+      assert_equal "some_value", text_verifier.verify(message)
       assert_raises ActiveSupport::MessageVerifier::InvalidSignature do
         default_verifier.verify(message)
       end
@@ -505,68 +505,68 @@ module ApplicationTests
     end
 
     test "secrets.secret_key_base is used when config/secrets.yml is present" do
-      app_file 'config/secrets.yml', <<-YAML
+      app_file "config/secrets.yml", <<-YAML
         development:
           secret_key_base: 3b7cd727ee24e8444053437c36cc66c3
       YAML
 
-      app 'development'
-      assert_equal '3b7cd727ee24e8444053437c36cc66c3', app.secrets.secret_key_base
+      app "development"
+      assert_equal "3b7cd727ee24e8444053437c36cc66c3", app.secrets.secret_key_base
     end
 
     test "secret_key_base is copied from config to secrets when not set" do
       remove_file "config/secrets.yml"
-      app_file 'config/initializers/secret_token.rb', <<-RUBY
+      app_file "config/initializers/secret_token.rb", <<-RUBY
         Rails.application.config.secret_key_base = "3b7cd727ee24e8444053437c36cc66c3"
       RUBY
 
-      app 'development'
-      assert_equal '3b7cd727ee24e8444053437c36cc66c3', app.secrets.secret_key_base
+      app "development"
+      assert_equal "3b7cd727ee24e8444053437c36cc66c3", app.secrets.secret_key_base
     end
 
     test "config.secret_token over-writes a blank secrets.secret_token" do
-      app_file 'config/initializers/secret_token.rb', <<-RUBY
+      app_file "config/initializers/secret_token.rb", <<-RUBY
         Rails.application.config.secret_token = "b3c631c314c0bbca50c1b2843150fe33"
       RUBY
-      app_file 'config/secrets.yml', <<-YAML
+      app_file "config/secrets.yml", <<-YAML
         development:
           secret_key_base:
           secret_token:
       YAML
 
-      app 'development'
+      app "development"
 
-      assert_equal 'b3c631c314c0bbca50c1b2843150fe33', app.secrets.secret_token
-      assert_equal 'b3c631c314c0bbca50c1b2843150fe33', app.config.secret_token
+      assert_equal "b3c631c314c0bbca50c1b2843150fe33", app.secrets.secret_token
+      assert_equal "b3c631c314c0bbca50c1b2843150fe33", app.config.secret_token
     end
 
     test "custom secrets saved in config/secrets.yml are loaded in app secrets" do
-      app_file 'config/secrets.yml', <<-YAML
+      app_file "config/secrets.yml", <<-YAML
         development:
           secret_key_base: 3b7cd727ee24e8444053437c36cc66c3
           aws_access_key_id: myamazonaccesskeyid
           aws_secret_access_key: myamazonsecretaccesskey
       YAML
 
-      app 'development'
+      app "development"
 
-      assert_equal 'myamazonaccesskeyid', app.secrets.aws_access_key_id
-      assert_equal 'myamazonsecretaccesskey', app.secrets.aws_secret_access_key
+      assert_equal "myamazonaccesskeyid", app.secrets.aws_access_key_id
+      assert_equal "myamazonsecretaccesskey", app.secrets.aws_secret_access_key
     end
 
     test "shared secrets saved in config/secrets.yml are loaded in app secrets" do
-      app_file 'config/secrets.yml', <<-YAML
+      app_file "config/secrets.yml", <<-YAML
         shared:
           api_key: 3b7cd727
       YAML
 
-      app 'development'
+      app "development"
 
-      assert_equal '3b7cd727', app.secrets.api_key
+      assert_equal "3b7cd727", app.secrets.api_key
     end
 
     test "shared secrets will yield to environment specific secrets" do
-      app_file 'config/secrets.yml', <<-YAML
+      app_file "config/secrets.yml", <<-YAML
         shared:
           api_key: 3b7cd727
 
@@ -574,62 +574,62 @@ module ApplicationTests
           api_key: abc12345
       YAML
 
-      app 'development'
+      app "development"
 
-      assert_equal 'abc12345', app.secrets.api_key
+      assert_equal "abc12345", app.secrets.api_key
     end
 
     test "blank config/secrets.yml does not crash the loading process" do
-      app_file 'config/secrets.yml', <<-YAML
+      app_file "config/secrets.yml", <<-YAML
       YAML
 
-      app 'development'
+      app "development"
 
       assert_nil app.secrets.not_defined
     end
 
     test "config.secret_key_base over-writes a blank secrets.secret_key_base" do
-      app_file 'config/initializers/secret_token.rb', <<-RUBY
+      app_file "config/initializers/secret_token.rb", <<-RUBY
         Rails.application.config.secret_key_base = "iaminallyoursecretkeybase"
       RUBY
-      app_file 'config/secrets.yml', <<-YAML
+      app_file "config/secrets.yml", <<-YAML
         development:
           secret_key_base:
       YAML
 
-      app 'development'
+      app "development"
 
       assert_equal "iaminallyoursecretkeybase", app.secrets.secret_key_base
     end
 
     test "uses ActiveSupport::LegacyKeyGenerator as app.key_generator when secrets.secret_key_base is blank" do
-      app_file 'config/initializers/secret_token.rb', <<-RUBY
+      app_file "config/initializers/secret_token.rb", <<-RUBY
         Rails.application.config.secret_token = "b3c631c314c0bbca50c1b2843150fe33"
       RUBY
-      app_file 'config/secrets.yml', <<-YAML
+      app_file "config/secrets.yml", <<-YAML
         development:
           secret_key_base:
       YAML
 
-      app 'development'
+      app "development"
 
-      assert_equal 'b3c631c314c0bbca50c1b2843150fe33', app.config.secret_token
+      assert_equal "b3c631c314c0bbca50c1b2843150fe33", app.config.secret_token
       assert_equal nil, app.secrets.secret_key_base
       assert_equal app.key_generator.class, ActiveSupport::LegacyKeyGenerator
     end
 
     test "uses ActiveSupport::LegacyKeyGenerator with config.secret_token as app.key_generator when secrets.secret_key_base is blank" do
-      app_file 'config/initializers/secret_token.rb', <<-RUBY
+      app_file "config/initializers/secret_token.rb", <<-RUBY
         Rails.application.config.secret_token = ""
       RUBY
-      app_file 'config/secrets.yml', <<-YAML
+      app_file "config/secrets.yml", <<-YAML
         development:
           secret_key_base:
       YAML
 
-      app 'development'
+      app "development"
 
-      assert_equal '', app.config.secret_token
+      assert_equal "", app.config.secret_token
       assert_equal nil, app.secrets.secret_key_base
       assert_raise ArgumentError, /\AA secret is required/ do
         app.key_generator
@@ -650,7 +650,7 @@ module ApplicationTests
     end
 
     test "default form builder specified as a string" do
-      app_file 'config/initializers/form_builder.rb', <<-RUBY
+      app_file "config/initializers/form_builder.rb", <<-RUBY
       class CustomFormBuilder < ActionView::Helpers::FormBuilder
         def text_field(attribute, *args)
           label(attribute) + super(attribute, *args)
@@ -659,7 +659,7 @@ module ApplicationTests
       Rails.configuration.action_view.default_form_builder = "CustomFormBuilder"
       RUBY
 
-      app_file 'app/models/post.rb', <<-RUBY
+      app_file "app/models/post.rb", <<-RUBY
       class Post
         include ActiveModel::Model
         attr_accessor :name
@@ -667,7 +667,7 @@ module ApplicationTests
       RUBY
 
 
-      app_file 'app/controllers/posts_controller.rb', <<-RUBY
+      app_file "app/controllers/posts_controller.rb", <<-RUBY
       class PostsController < ApplicationController
         def index
           render inline: "<%= begin; form_for(Post.new) {|f| f.text_field(:name)}; rescue => e; e.to_s; end %>"
@@ -681,14 +681,14 @@ module ApplicationTests
         end
       RUBY
 
-      app 'development'
+      app "development"
 
       get "/posts"
       assert_match(/label/, last_response.body)
     end
 
     test "default method for update can be changed" do
-      app_file 'app/models/post.rb', <<-RUBY
+      app_file "app/models/post.rb", <<-RUBY
       class Post
         include ActiveModel::Model
         def to_key; [1]; end
@@ -698,7 +698,7 @@ module ApplicationTests
 
       token = "cf50faa3fe97702ca1ae"
 
-      app_file 'app/controllers/posts_controller.rb', <<-RUBY
+      app_file "app/controllers/posts_controller.rb", <<-RUBY
       class PostsController < ApplicationController
         def show
           render inline: "<%= begin; form_for(Post.new) {}; rescue => e; e.to_s; end %>"
@@ -720,7 +720,7 @@ module ApplicationTests
         end
       RUBY
 
-      app 'development'
+      app "development"
 
       params = { authenticity_token: token }
 
@@ -742,7 +742,7 @@ module ApplicationTests
 
     test "request forgery token param can be changed" do
       make_basic_app do |application|
-        application.config.action_controller.request_forgery_protection_token = '_xsrf_token_here'
+        application.config.action_controller.request_forgery_protection_token = "_xsrf_token_here"
       end
 
       class ::OmgController < ActionController::Base
@@ -773,7 +773,7 @@ module ApplicationTests
         config.action_mailer.interceptors = MyMailInterceptor
       RUBY
 
-      app 'development'
+      app "development"
 
       require "mail"
       _ = ActionMailer::Base
@@ -786,7 +786,7 @@ module ApplicationTests
         config.action_mailer.interceptors = [MyMailInterceptor, "MyOtherMailInterceptor"]
       RUBY
 
-      app 'development'
+      app "development"
 
       require "mail"
       _ = ActionMailer::Base
@@ -799,7 +799,7 @@ module ApplicationTests
         config.action_mailer.preview_interceptors = MyPreviewMailInterceptor
       RUBY
 
-      app 'development'
+      app "development"
 
       require "mail"
       _ = ActionMailer::Base
@@ -812,7 +812,7 @@ module ApplicationTests
         config.action_mailer.preview_interceptors = [MyPreviewMailInterceptor, "MyOtherPreviewMailInterceptor"]
       RUBY
 
-      app 'development'
+      app "development"
 
       require "mail"
       _ = ActionMailer::Base
@@ -821,11 +821,11 @@ module ApplicationTests
     end
 
     test "default preview interceptor can be removed" do
-      app_file 'config/initializers/preview_interceptors.rb', <<-RUBY
+      app_file "config/initializers/preview_interceptors.rb", <<-RUBY
         ActionMailer::Base.preview_interceptors.delete(ActionMailer::InlinePreviewInterceptor)
       RUBY
 
-      app 'development'
+      app "development"
 
       require "mail"
       _ = ActionMailer::Base
@@ -838,7 +838,7 @@ module ApplicationTests
         config.action_mailer.observers = MyMailObserver
       RUBY
 
-      app 'development'
+      app "development"
 
       require "mail"
       _ = ActionMailer::Base
@@ -851,7 +851,7 @@ module ApplicationTests
         config.action_mailer.observers = [MyMailObserver, "MyOtherMailObserver"]
       RUBY
 
-      app 'development'
+      app "development"
 
       require "mail"
       _ = ActionMailer::Base
@@ -864,12 +864,12 @@ module ApplicationTests
         config.action_mailer.deliver_later_queue_name = 'test_default'
       RUBY
 
-      app 'development'
+      app "development"
 
       require "mail"
       _ = ActionMailer::Base
 
-      assert_equal 'test_default', ActionMailer::Base.class_variable_get(:@@deliver_later_queue_name)
+      assert_equal "test_default", ActionMailer::Base.class_variable_get(:@@deliver_later_queue_name)
     end
 
     test "valid timezone is setup correctly" do
@@ -878,7 +878,7 @@ module ApplicationTests
         config.time_zone = "Wellington"
       RUBY
 
-      app 'development'
+      app "development"
 
       assert_equal "Wellington", Rails.application.config.time_zone
     end
@@ -890,7 +890,7 @@ module ApplicationTests
       RUBY
 
       assert_raise(ArgumentError) do
-        app 'development'
+        app "development"
       end
     end
 
@@ -900,7 +900,7 @@ module ApplicationTests
         config.beginning_of_week = :wednesday
       RUBY
 
-      app 'development'
+      app "development"
 
       assert_equal :wednesday, Rails.application.config.beginning_of_week
     end
@@ -912,15 +912,15 @@ module ApplicationTests
       RUBY
 
       assert_raise(ArgumentError) do
-        app 'development'
+        app "development"
       end
     end
 
     test "config.action_view.cache_template_loading with cache_classes default" do
       add_to_config "config.cache_classes = true"
 
-      app 'development'
-      require 'action_view/base'
+      app "development"
+      require "action_view/base"
 
       assert_equal true, ActionView::Resolver.caching?
     end
@@ -928,8 +928,8 @@ module ApplicationTests
     test "config.action_view.cache_template_loading without cache_classes default" do
       add_to_config "config.cache_classes = false"
 
-      app 'development'
-      require 'action_view/base'
+      app "development"
+      require "action_view/base"
 
       assert_equal false, ActionView::Resolver.caching?
     end
@@ -940,8 +940,8 @@ module ApplicationTests
         config.action_view.cache_template_loading = false
       RUBY
 
-      app 'development'
-      require 'action_view/base'
+      app "development"
+      require "action_view/base"
 
       assert_equal false, ActionView::Resolver.caching?
     end
@@ -952,8 +952,8 @@ module ApplicationTests
         config.action_view.cache_template_loading = true
       RUBY
 
-      app 'development'
-      require 'action_view/base'
+      app "development"
+      require "action_view/base"
 
       assert_equal true, ActionView::Resolver.caching?
     end
@@ -963,11 +963,11 @@ module ApplicationTests
       add_to_env_config "development", "config.cache_classes = false"
 
       # These requires are to emulate an engine loading Action View before the application
-      require 'action_view'
-      require 'action_view/railtie'
-      require 'action_view/base'
+      require "action_view"
+      require "action_view/railtie"
+      require "action_view/base"
 
-      app 'development'
+      app "development"
 
       assert_equal false, ActionView::Resolver.caching?
     end
@@ -984,15 +984,15 @@ module ApplicationTests
       end
 
       get "/"
-      assert_equal 'true', last_response.body
+      assert_equal "true", last_response.body
     end
 
     test "config.action_controller.wrap_parameters is set in ActionController::Base" do
-      app_file 'config/initializers/wrap_parameters.rb', <<-RUBY
+      app_file "config/initializers/wrap_parameters.rb", <<-RUBY
         ActionController::Base.wrap_parameters format: [:json]
       RUBY
 
-      app_file 'app/models/post.rb', <<-RUBY
+      app_file "app/models/post.rb", <<-RUBY
       class Post
         def self.attribute_names
           %w(title)
@@ -1000,13 +1000,13 @@ module ApplicationTests
       end
       RUBY
 
-      app_file 'app/controllers/application_controller.rb', <<-RUBY
+      app_file "app/controllers/application_controller.rb", <<-RUBY
       class ApplicationController < ActionController::Base
         protect_from_forgery with: :reset_session # as we are testing API here
       end
       RUBY
 
-      app_file 'app/controllers/posts_controller.rb', <<-RUBY
+      app_file "app/controllers/posts_controller.rb", <<-RUBY
       class PostsController < ApplicationController
         def create
           render text: params[:post].inspect
@@ -1020,14 +1020,14 @@ module ApplicationTests
         end
       RUBY
 
-      app 'development'
+      app "development"
 
       post "/posts.json", '{ "title": "foo", "name": "bar" }', "CONTENT_TYPE" => "application/json"
       assert_equal '<ActionController::Parameters {"title"=>"foo"} permitted: false>', last_response.body
     end
 
     test "config.action_controller.permit_all_parameters = true" do
-      app_file 'app/controllers/posts_controller.rb', <<-RUBY
+      app_file "app/controllers/posts_controller.rb", <<-RUBY
       class PostsController < ActionController::Base
         def create
           render text: params[:post].permitted? ? "permitted" : "forbidden"
@@ -1042,14 +1042,14 @@ module ApplicationTests
         config.action_controller.permit_all_parameters = true
       RUBY
 
-      app 'development'
+      app "development"
 
       post "/posts", {post: {"title" =>"zomg"}}
-      assert_equal 'permitted', last_response.body
+      assert_equal "permitted", last_response.body
     end
 
     test "config.action_controller.action_on_unpermitted_parameters = :raise" do
-      app_file 'app/controllers/posts_controller.rb', <<-RUBY
+      app_file "app/controllers/posts_controller.rb", <<-RUBY
       class PostsController < ActionController::Base
         def create
           render text: params.require(:post).permit(:name)
@@ -1064,7 +1064,7 @@ module ApplicationTests
         config.action_controller.action_on_unpermitted_parameters = :raise
       RUBY
 
-      app 'development'
+      app "development"
 
       assert_equal :raise, ActionController::Parameters.action_on_unpermitted_parameters
 
@@ -1073,7 +1073,7 @@ module ApplicationTests
     end
 
     test "config.action_controller.always_permitted_parameters are: controller, action by default" do
-      app 'development'
+      app "development"
       assert_equal %w(controller action), ActionController::Parameters.always_permitted_parameters
     end
 
@@ -1082,13 +1082,13 @@ module ApplicationTests
         config.action_controller.always_permitted_parameters = %w( controller action format )
       RUBY
 
-      app 'development'
+      app "development"
 
       assert_equal %w( controller action format ), ActionController::Parameters.always_permitted_parameters
     end
 
     test "config.action_controller.always_permitted_parameters = ['controller','action','format'] does not raise exception" do
-      app_file 'app/controllers/posts_controller.rb', <<-RUBY
+      app_file "app/controllers/posts_controller.rb", <<-RUBY
       class PostsController < ActionController::Base
         def create
           render text: params.permit(post: [:title])
@@ -1104,7 +1104,7 @@ module ApplicationTests
         config.action_controller.action_on_unpermitted_parameters = :raise
       RUBY
 
-      app 'development'
+      app "development"
 
       assert_equal :raise, ActionController::Parameters.action_on_unpermitted_parameters
 
@@ -1113,19 +1113,19 @@ module ApplicationTests
     end
 
     test "config.action_controller.action_on_unpermitted_parameters is :log by default on development" do
-      app 'development'
+      app "development"
 
       assert_equal :log, ActionController::Parameters.action_on_unpermitted_parameters
     end
 
     test "config.action_controller.action_on_unpermitted_parameters is :log by default on test" do
-      app 'test'
+      app "test"
 
       assert_equal :log, ActionController::Parameters.action_on_unpermitted_parameters
     end
 
     test "config.action_controller.action_on_unpermitted_parameters is false by default on production" do
-      app 'production'
+      app "production"
 
       assert_equal false, ActionController::Parameters.action_on_unpermitted_parameters
     end
@@ -1145,21 +1145,21 @@ module ApplicationTests
       end
 
       get "/", {}, "HTTP_ACCEPT" => "application/xml"
-      assert_equal 'HTML', last_response.body
+      assert_equal "HTML", last_response.body
 
       get "/", { format: :xml }, "HTTP_ACCEPT" => "application/xml"
-      assert_equal 'XML', last_response.body
+      assert_equal "XML", last_response.body
     end
 
     test "Rails.application#env_config exists and include some existing parameters" do
       make_basic_app
 
       assert_respond_to app, :env_config
-      assert_equal      app.env_config['action_dispatch.parameter_filter'],  app.config.filter_parameters
-      assert_equal      app.env_config['action_dispatch.show_exceptions'],   app.config.action_dispatch.show_exceptions
-      assert_equal      app.env_config['action_dispatch.logger'],            Rails.logger
-      assert_equal      app.env_config['action_dispatch.backtrace_cleaner'], Rails.backtrace_cleaner
-      assert_equal      app.env_config['action_dispatch.key_generator'],     Rails.application.key_generator
+      assert_equal      app.env_config["action_dispatch.parameter_filter"],  app.config.filter_parameters
+      assert_equal      app.env_config["action_dispatch.show_exceptions"],   app.config.action_dispatch.show_exceptions
+      assert_equal      app.env_config["action_dispatch.logger"],            Rails.logger
+      assert_equal      app.env_config["action_dispatch.backtrace_cleaner"], Rails.backtrace_cleaner
+      assert_equal      app.env_config["action_dispatch.key_generator"],     Rails.application.key_generator
     end
 
     test "config.colorize_logging default is true" do
@@ -1220,13 +1220,13 @@ module ApplicationTests
     test "config.active_record.dump_schema_after_migration is false on production" do
       build_app
 
-      app 'production'
+      app "production"
 
       assert_not ActiveRecord::Base.dump_schema_after_migration
     end
 
     test "config.active_record.dump_schema_after_migration is true by default on development" do
-      app 'development'
+      app "development"
 
       assert ActiveRecord::Base.dump_schema_after_migration
     end
@@ -1252,12 +1252,12 @@ module ApplicationTests
         end
       RUBY
 
-      app 'development'
+      app "development"
       assert_not Rails.configuration.ran_block
 
-      require 'rake'
-      require 'rake/testtask'
-      require 'rdoc/task'
+      require "rake"
+      require "rake/testtask"
+      require "rdoc/task"
 
       Rails.application.load_tasks
       assert Rails.configuration.ran_block
@@ -1274,7 +1274,7 @@ module ApplicationTests
         end
       RUBY
 
-      app 'development'
+      app "development"
       assert_not Rails.configuration.ran_block
 
       Rails.application.load_generators
@@ -1292,7 +1292,7 @@ module ApplicationTests
         end
       RUBY
 
-      app 'development'
+      app "development"
       assert_not Rails.configuration.ran_block
 
       Rails.application.load_console
@@ -1310,7 +1310,7 @@ module ApplicationTests
         end
       RUBY
 
-      app 'development'
+      app "development"
       assert_not Rails.configuration.ran_block
 
       Rails.application.load_runner
@@ -1318,7 +1318,7 @@ module ApplicationTests
     end
 
     test "loading the first existing database configuration available" do
-      app_file 'config/environments/development.rb', <<-RUBY
+      app_file "config/environments/development.rb", <<-RUBY
 
       Rails.application.configure do
         config.paths.add 'config/database', with: 'config/nonexistent.yml'
@@ -1326,44 +1326,44 @@ module ApplicationTests
         end
       RUBY
 
-      app 'development'
+      app "development"
 
       assert_kind_of Hash, Rails.application.config.database_configuration
     end
 
-    test 'raises with proper error message if no database configuration found' do
+    test "raises with proper error message if no database configuration found" do
       FileUtils.rm("#{app_path}/config/database.yml")
-      app 'development'
+      app "development"
       err = assert_raises RuntimeError do
         Rails.application.config.database_configuration
       end
-      assert_match 'config/database', err.message
+      assert_match "config/database", err.message
     end
 
-    test 'config.action_mailer.show_previews defaults to true in development' do
-      app 'development'
+    test "config.action_mailer.show_previews defaults to true in development" do
+      app "development"
 
       assert Rails.application.config.action_mailer.show_previews
     end
 
-    test 'config.action_mailer.show_previews defaults to false in production' do
-      app 'production'
+    test "config.action_mailer.show_previews defaults to false in production" do
+      app "production"
 
       assert_equal false, Rails.application.config.action_mailer.show_previews
     end
 
-    test 'config.action_mailer.show_previews can be set in the configuration file' do
+    test "config.action_mailer.show_previews can be set in the configuration file" do
       add_to_config <<-RUBY
         config.action_mailer.show_previews = true
       RUBY
 
-      app 'production'
+      app "production"
 
       assert_equal true, Rails.application.config.action_mailer.show_previews
     end
 
     test "config_for loads custom configuration from yaml files" do
-      app_file 'config/custom.yml', <<-RUBY
+      app_file "config/custom.yml", <<-RUBY
       development:
         key: 'custom key'
       RUBY
@@ -1372,13 +1372,13 @@ module ApplicationTests
         config.my_custom_config = config_for('custom')
       RUBY
 
-      app 'development'
+      app "development"
 
-      assert_equal 'custom key', Rails.application.config.my_custom_config['key']
+      assert_equal "custom key", Rails.application.config.my_custom_config["key"]
     end
 
     test "config_for uses the Pathname object if it is provided" do
-      app_file 'config/custom.yml', <<-RUBY
+      app_file "config/custom.yml", <<-RUBY
       development:
         key: 'custom key'
       RUBY
@@ -1387,9 +1387,9 @@ module ApplicationTests
         config.my_custom_config = config_for(Pathname.new(Rails.root.join("config/custom.yml")))
       RUBY
 
-      app 'development'
+      app "development"
 
-      assert_equal 'custom key', Rails.application.config.my_custom_config['key']
+      assert_equal "custom key", Rails.application.config.my_custom_config["key"]
     end
 
     test "config_for raises an exception if the file does not exist" do
@@ -1398,14 +1398,14 @@ module ApplicationTests
       RUBY
 
       exception = assert_raises(RuntimeError) do
-        app 'development'
+        app "development"
       end
 
       assert_equal "Could not load configuration. No such file - #{app_path}/config/custom.yml", exception.message
     end
 
     test "config_for without the environment configured returns an empty hash" do
-      app_file 'config/custom.yml', <<-RUBY
+      app_file "config/custom.yml", <<-RUBY
       test:
         key: 'custom key'
       RUBY
@@ -1414,26 +1414,26 @@ module ApplicationTests
         config.my_custom_config = config_for('custom')
       RUBY
 
-      app 'development'
+      app "development"
 
       assert_equal({}, Rails.application.config.my_custom_config)
     end
 
     test "config_for with empty file returns an empty hash" do
-      app_file 'config/custom.yml', <<-RUBY
+      app_file "config/custom.yml", <<-RUBY
       RUBY
 
       add_to_config <<-RUBY
         config.my_custom_config = config_for('custom')
       RUBY
 
-      app 'development'
+      app "development"
 
       assert_equal({}, Rails.application.config.my_custom_config)
     end
 
     test "config_for containing ERB tags should evaluate" do
-      app_file 'config/custom.yml', <<-RUBY
+      app_file "config/custom.yml", <<-RUBY
       development:
         key: <%= 'custom key' %>
       RUBY
@@ -1442,13 +1442,13 @@ module ApplicationTests
         config.my_custom_config = config_for('custom')
       RUBY
 
-      app 'development'
+      app "development"
 
-      assert_equal 'custom key', Rails.application.config.my_custom_config['key']
+      assert_equal "custom key", Rails.application.config.my_custom_config["key"]
     end
 
     test "config_for with syntax error show a more descriptive exception" do
-      app_file 'config/custom.yml', <<-RUBY
+      app_file "config/custom.yml", <<-RUBY
       development:
         key: foo:
       RUBY
@@ -1458,14 +1458,14 @@ module ApplicationTests
       RUBY
 
       exception = assert_raises(RuntimeError) do
-        app 'development'
+        app "development"
       end
 
-      assert_match 'YAML syntax error occurred while parsing', exception.message
+      assert_match "YAML syntax error occurred while parsing", exception.message
     end
 
     test "config_for allows overriding the environment" do
-      app_file 'config/custom.yml', <<-RUBY
+      app_file "config/custom.yml", <<-RUBY
         test:
           key: 'walrus'
         production:
@@ -1477,11 +1477,11 @@ module ApplicationTests
       RUBY
       require "#{app_path}/config/environment"
 
-      assert_equal 'unicorn', Rails.application.config.my_custom_config['key']
+      assert_equal "unicorn", Rails.application.config.my_custom_config["key"]
     end
 
     test "api_only is false by default" do
-      app 'development'
+      app "development"
       refute Rails.application.config.api_only
     end
 
@@ -1489,7 +1489,7 @@ module ApplicationTests
       add_to_config <<-RUBY
         config.api_only = true
       RUBY
-      app 'development'
+      app "development"
 
       Rails.application.load_generators
       assert Rails.configuration.api_only
@@ -1499,7 +1499,7 @@ module ApplicationTests
       add_to_config <<-RUBY
         config.api_only = true
       RUBY
-      app 'development'
+      app "development"
 
       assert_equal :api, Rails.configuration.debug_exception_response_format
     end
@@ -1509,13 +1509,13 @@ module ApplicationTests
         config.api_only = true
       RUBY
 
-      app_file 'config/environments/development.rb', <<-RUBY
+      app_file "config/environments/development.rb", <<-RUBY
       Rails.application.configure do
         config.debug_exception_response_format = :default
       end
       RUBY
 
-      app 'development'
+      app "development"
 
       assert_equal :default, Rails.configuration.debug_exception_response_format
     end
diff --git a/railties/test/application/console_test.rb b/railties/test/application/console_test.rb
index ba60b54df3..3b8062f74b 100644
--- a/railties/test/application/console_test.rb
+++ b/railties/test/application/console_test.rb
@@ -1,4 +1,4 @@
-require 'isolation/abstract_unit'
+require "isolation/abstract_unit"
 
 class ConsoleTest < ActiveSupport::TestCase
   include ActiveSupport::Testing::Isolation
@@ -29,7 +29,7 @@ class ConsoleTest < ActiveSupport::TestCase
   end
 
   def test_app_can_access_path_helper_method
-    app_file 'config/routes.rb', <<-RUBY
+    app_file "config/routes.rb", <<-RUBY
       Rails.application.routes.draw do
         get 'foo', to: 'foo#index'
       end
@@ -37,7 +37,7 @@ class ConsoleTest < ActiveSupport::TestCase
 
     load_environment
     console_session = irb_context.app
-    assert_equal '/foo', console_session.foo_path
+    assert_equal "/foo", console_session.foo_path
   end
 
   def test_new_session_should_return_integration_session
@@ -88,8 +88,8 @@ class ConsoleTest < ActiveSupport::TestCase
     helper = irb_context.helper
     assert_not_nil helper
     assert_instance_of ActionView::Base, helper
-    assert_equal 'Once upon a time in a world...',
-      helper.truncate('Once upon a time in a world far far away')
+    assert_equal "Once upon a time in a world...",
+      helper.truncate("Once upon a time in a world far far away")
   end
 end
 
@@ -103,7 +103,7 @@ class FullStackConsoleTest < ActiveSupport::TestCase
     skip "PTY unavailable" unless defined?(PTY) && PTY.respond_to?(:open)
 
     build_app
-    app_file 'app/models/post.rb', <<-CODE
+    app_file "app/models/post.rb", <<-CODE
       class Post < ActiveRecord::Base
       end
     CODE
diff --git a/railties/test/application/generators_test.rb b/railties/test/application/generators_test.rb
index 4e300bce63..0d7ccb2278 100644
--- a/railties/test/application/generators_test.rb
+++ b/railties/test/application/generators_test.rb
@@ -113,7 +113,7 @@ module ApplicationTests
     test "generators with string and hash for options should generate symbol keys" do
       with_bare_config do |c|
         c.generators do |g|
-          g.orm    'data_mapper', migration: false
+          g.orm    "data_mapper", migration: false
         end
 
         expected = {
diff --git a/railties/test/application/initializers/frameworks_test.rb b/railties/test/application/initializers/frameworks_test.rb
index 812bb87009..b2cd339c1a 100644
--- a/railties/test/application/initializers/frameworks_test.rb
+++ b/railties/test/application/initializers/frameworks_test.rb
@@ -128,7 +128,7 @@ module ApplicationTests
         end
       RUBY
 
-      require 'rack/test'
+      require "rack/test"
       extend Rack::Test::Methods
 
       get "/foo/included_helpers"
@@ -160,10 +160,10 @@ module ApplicationTests
         end
       RUBY
 
-      require 'rack/test'
+      require "rack/test"
       extend Rack::Test::Methods
 
-      get 'omg/show'
+      get "omg/show"
       assert_equal '{"omg":"omg"}', last_response.body
     end
 
@@ -175,7 +175,7 @@ module ApplicationTests
     end
 
     test "assignment config.encoding to default_charset" do
-      charset = 'Shift_JIS'
+      charset = "Shift_JIS"
       add_to_config "config.encoding = '#{charset}'"
       require "#{app_path}/config/environment"
       assert_equal charset, ActionDispatch::Response.default_charset
@@ -203,7 +203,7 @@ module ApplicationTests
     test "active_record extensions are applied to ActiveRecord" do
       add_to_config "config.active_record.table_name_prefix = 'tbl_'"
       require "#{app_path}/config/environment"
-      assert_equal 'tbl_', ActiveRecord::Base.table_name_prefix
+      assert_equal "tbl_", ActiveRecord::Base.table_name_prefix
     end
 
     test "database middleware doesn't initialize when activerecord is not in frameworks" do
@@ -237,7 +237,7 @@ module ApplicationTests
       begin
         require "#{app_path}/config/environment"
         orig_database_url = ENV.delete("DATABASE_URL")
-        orig_rails_env, Rails.env = Rails.env, 'development'
+        orig_rails_env, Rails.env = Rails.env, "development"
         ActiveRecord::Base.establish_connection
         assert ActiveRecord::Base.connection
         assert_match(/#{ActiveRecord::Base.configurations[Rails.env]['database']}/, ActiveRecord::Base.connection_config[:database])
@@ -252,7 +252,7 @@ module ApplicationTests
       begin
         require "#{app_path}/config/environment"
         orig_database_url = ENV.delete("DATABASE_URL")
-        orig_rails_env, Rails.env = Rails.env, 'development'
+        orig_rails_env, Rails.env = Rails.env, "development"
         database_url_db_name = "db/database_url_db.sqlite3"
         ENV["DATABASE_URL"] = "sqlite3:#{database_url_db_name}"
         ActiveRecord::Base.establish_connection
diff --git a/railties/test/application/initializers/hooks_test.rb b/railties/test/application/initializers/hooks_test.rb
index 3c0c2ac1c0..0309d02730 100644
--- a/railties/test/application/initializers/hooks_test.rb
+++ b/railties/test/application/initializers/hooks_test.rb
@@ -57,7 +57,7 @@ module ApplicationTests
 
       require "#{app_path}/config/environment"
       assert $activerecord_configurations
-      assert $activerecord_configurations['development']
+      assert $activerecord_configurations["development"]
     end
 
     test "after_initialize happens after to_prepare in development" do
diff --git a/railties/test/application/initializers/i18n_test.rb b/railties/test/application/initializers/i18n_test.rb
index fcafbb6d04..2b407e4351 100644
--- a/railties/test/application/initializers/i18n_test.rb
+++ b/railties/test/application/initializers/i18n_test.rb
@@ -76,19 +76,19 @@ en:
   foo: "1"
       YAML
 
-      app_file 'app/models/foo.rb', <<-RUBY
+      app_file "app/models/foo.rb", <<-RUBY
         class Foo < ActiveRecord::Base
           @foo = I18n.t(:foo)
         end
       RUBY
 
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get '/i18n',   :to => lambda { |env| [200, {}, [Foo.instance_variable_get('@foo')]] }
         end
       RUBY
 
-      require 'rack/test'
+      require "rack/test"
       extend Rack::Test::Methods
       load_app
 
@@ -106,13 +106,13 @@ en:
   foo: "1"
       YAML
 
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get '/i18n',   :to => lambda { |env| [200, {}, [I18n.t(:foo)]] }
         end
       RUBY
 
-      require 'rack/test'
+      require "rack/test"
       extend Rack::Test::Methods
       load_app
 
@@ -141,13 +141,13 @@ en:
   foo: "1"
       YAML
 
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get '/i18n',   :to => lambda { |env| [200, {}, [I18n.t(:foo)]] }
         end
       RUBY
 
-      require 'rack/test'
+      require "rack/test"
       extend Rack::Test::Methods
       load_app
 
@@ -177,13 +177,13 @@ en:
   foo: "1"
       YAML
 
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get '/i18n',   :to => lambda { |env| [200, {}, [I18n.load_path.inspect]] }
         end
       RUBY
 
-      require 'rack/test'
+      require "rack/test"
       extend Rack::Test::Methods
       load_app
 
diff --git a/railties/test/application/initializers/notifications_test.rb b/railties/test/application/initializers/notifications_test.rb
index 1a7914b4eb..b847ac6b36 100644
--- a/railties/test/application/initializers/notifications_test.rb
+++ b/railties/test/application/initializers/notifications_test.rb
@@ -39,17 +39,17 @@ module ApplicationTests
       assert_match(/SHOW tables/, logger.logged(:debug).last)
     end
 
-    test 'rails load_config_initializer event is instrumented' do
-      app_file 'config/initializers/foo.rb', ''
+    test "rails load_config_initializer event is instrumented" do
+      app_file "config/initializers/foo.rb", ""
 
       events = []
       callback = ->(*_) { events << _ }
-      ActiveSupport::Notifications.subscribed(callback, 'load_config_initializer.railties') do
+      ActiveSupport::Notifications.subscribed(callback, "load_config_initializer.railties") do
         app
       end
 
       assert_equal %w[load_config_initializer.railties], events.map(&:first)
-      assert_includes events.first.last[:initializer], 'config/initializers/foo.rb'
+      assert_includes events.first.last[:initializer], "config/initializers/foo.rb"
     end
   end
 end
diff --git a/railties/test/application/integration_test_case_test.rb b/railties/test/application/integration_test_case_test.rb
index 68e2de80c4..1118e5037a 100644
--- a/railties/test/application/integration_test_case_test.rb
+++ b/railties/test/application/integration_test_case_test.rb
@@ -1,4 +1,4 @@
-require 'isolation/abstract_unit'
+require "isolation/abstract_unit"
 
 module ApplicationTests
   class IntegrationTestCaseTest < ActiveSupport::TestCase
@@ -13,9 +13,9 @@ module ApplicationTests
     end
 
     test "resets Action Mailer test deliveries" do
-      script('generate mailer BaseMailer welcome')
+      script("generate mailer BaseMailer welcome")
 
-      app_file 'test/integration/mailer_integration_test.rb', <<-RUBY
+      app_file "test/integration/mailer_integration_test.rb", <<-RUBY
         require 'test_helper'
 
         class MailerIntegrationTest < ActionDispatch::IntegrationTest
@@ -55,7 +55,7 @@ module ApplicationTests
     end
 
     test "app method of integration tests returns test_app by default" do
-      app_file 'test/integration/default_app_test.rb', <<-RUBY
+      app_file "test/integration/default_app_test.rb", <<-RUBY
         require 'test_helper'
 
         class DefaultAppIntegrationTest < ActionDispatch::IntegrationTest
diff --git a/railties/test/application/loading_test.rb b/railties/test/application/loading_test.rb
index fe1847d8a5..18f8c89790 100644
--- a/railties/test/application/loading_test.rb
+++ b/railties/test/application/loading_test.rb
@@ -1,4 +1,4 @@
-require 'isolation/abstract_unit'
+require "isolation/abstract_unit"
 
 class LoadingTest < ActiveSupport::TestCase
   include ActiveSupport::Testing::Isolation
@@ -25,11 +25,11 @@ class LoadingTest < ActiveSupport::TestCase
     require "#{rails_root}/config/environment"
     setup_ar!
 
-    p = Post.create(title: 'omg')
+    p = Post.create(title: "omg")
     assert_equal 1, Post.count
-    assert_equal 'omg', p.title
+    assert_equal "omg", p.title
     p = Post.first
-    assert_equal 'omg', p.title
+    assert_equal "omg", p.title
   end
 
   test "concerns in app are autoloaded" do
@@ -102,14 +102,14 @@ class LoadingTest < ActiveSupport::TestCase
       end
     MODEL
 
-    app_file 'config/routes.rb', <<-RUBY
+    app_file "config/routes.rb", <<-RUBY
       Rails.application.routes.draw do
         get '/load',   to: lambda { |env| [200, {}, Post.all] }
         get '/unload', to: lambda { |env| [200, {}, []] }
       end
     RUBY
 
-    require 'rack/test'
+    require "rack/test"
     extend Rack::Test::Methods
 
     require "#{rails_root}/config/environment"
@@ -132,7 +132,7 @@ class LoadingTest < ActiveSupport::TestCase
       config.cache_classes = false
     RUBY
 
-    app_file 'config/routes.rb', <<-RUBY
+    app_file "config/routes.rb", <<-RUBY
       Rails.application.routes.draw do
         get '/c', to: lambda { |env| [200, {"Content-Type" => "text/plain"}, [User.counter.to_s]] }
       end
@@ -144,7 +144,7 @@ class LoadingTest < ActiveSupport::TestCase
       end
     MODEL
 
-    require 'rack/test'
+    require "rack/test"
     extend Rack::Test::Methods
 
     require "#{rails_root}/config/environment"
@@ -173,7 +173,7 @@ class LoadingTest < ActiveSupport::TestCase
       end
     RUBY
 
-    app_file 'config/routes.rb', <<-RUBY
+    app_file "config/routes.rb", <<-RUBY
       Rails.application.routes.draw do
         get '/c', to: lambda { |env| [200, {"Content-Type" => "text/plain"}, [User.counter.to_s]] }
       end
@@ -185,7 +185,7 @@ class LoadingTest < ActiveSupport::TestCase
       end
     MODEL
 
-    require 'rack/test'
+    require "rack/test"
     extend Rack::Test::Methods
 
     require "#{rails_root}/config/environment"
@@ -208,7 +208,7 @@ class LoadingTest < ActiveSupport::TestCase
       config.cache_classes = false
     RUBY
 
-    app_file 'config/routes.rb', <<-RUBY
+    app_file "config/routes.rb", <<-RUBY
       $counter ||= 0
       Rails.application.routes.draw do
         get '/c', to: lambda { |env| User.name; [200, {"Content-Type" => "text/plain"}, [$counter.to_s]] }
@@ -221,7 +221,7 @@ class LoadingTest < ActiveSupport::TestCase
       end
     MODEL
 
-    require 'rack/test'
+    require "rack/test"
     extend Rack::Test::Methods
 
     require "#{rails_root}/config/environment"
@@ -240,7 +240,7 @@ class LoadingTest < ActiveSupport::TestCase
       config.cache_classes = false
     RUBY
 
-    app_file 'config/routes.rb', <<-RUBY
+    app_file "config/routes.rb", <<-RUBY
       $counter ||= 1
       $counter  *= 2
       Rails.application.routes.draw do
@@ -254,7 +254,7 @@ class LoadingTest < ActiveSupport::TestCase
       end
     MODEL
 
-    require 'rack/test'
+    require "rack/test"
     extend Rack::Test::Methods
 
     require "#{rails_root}/config/environment"
@@ -273,7 +273,7 @@ class LoadingTest < ActiveSupport::TestCase
       config.cache_classes = false
     RUBY
 
-    app_file 'config/routes.rb', <<-RUBY
+    app_file "config/routes.rb", <<-RUBY
       Rails.application.routes.draw do
         get '/title', to: lambda { |env| [200, {"Content-Type" => "text/plain"}, [Post.new.title]] }
         get '/body',  to: lambda { |env| [200, {"Content-Type" => "text/plain"}, [Post.new.body]] }
@@ -285,7 +285,7 @@ class LoadingTest < ActiveSupport::TestCase
       end
     MODEL
 
-    require 'rack/test'
+    require "rack/test"
     extend Rack::Test::Methods
 
     app_file "db/migrate/1_create_posts.rb", <<-MIGRATION
@@ -340,11 +340,11 @@ class LoadingTest < ActiveSupport::TestCase
 
     require "#{rails_root}/config/environment"
 
-    require 'rack/test'
+    require "rack/test"
     extend Rack::Test::Methods
 
-    get '/omg/show'
-    assert_equal 'OK', last_response.body
+    get "/omg/show"
+    assert_equal "OK", last_response.body
   end
 
   def test_initialize_can_be_called_at_any_time
diff --git a/railties/test/application/mailer_previews_test.rb b/railties/test/application/mailer_previews_test.rb
index 3ea74423cf..18e3a7bf0e 100644
--- a/railties/test/application/mailer_previews_test.rb
+++ b/railties/test/application/mailer_previews_test.rb
@@ -1,6 +1,6 @@
-require 'isolation/abstract_unit'
-require 'rack/test'
-require 'base64'
+require "isolation/abstract_unit"
+require "rack/test"
+require "base64"
 
 module ApplicationTests
   class MailerPreviewsTest < ActiveSupport::TestCase
@@ -53,7 +53,7 @@ module ApplicationTests
     end
 
     test "mailer previews are loaded from the default preview_path" do
-      mailer 'notifier', <<-RUBY
+      mailer "notifier", <<-RUBY
         class Notifier < ActionMailer::Base
           default from: "from@example.com"
 
@@ -63,11 +63,11 @@ module ApplicationTests
         end
       RUBY
 
-      text_template 'notifier/foo', <<-RUBY
+      text_template "notifier/foo", <<-RUBY
         Hello, World!
       RUBY
 
-      mailer_preview 'notifier', <<-RUBY
+      mailer_preview "notifier", <<-RUBY
         class NotifierPreview < ActionMailer::Preview
           def foo
             Notifier.foo
@@ -75,7 +75,7 @@ module ApplicationTests
         end
       RUBY
 
-      app('development')
+      app("development")
 
       get "/rails/mailers"
       assert_match '<h3><a href="/rails/mailers/notifier">Notifier</a></h3>', last_response.body
@@ -85,7 +85,7 @@ module ApplicationTests
     test "mailer previews are loaded from a custom preview_path" do
       add_to_config "config.action_mailer.preview_path = '#{app_path}/lib/mailer_previews'"
 
-      mailer 'notifier', <<-RUBY
+      mailer "notifier", <<-RUBY
         class Notifier < ActionMailer::Base
           default from: "from@example.com"
 
@@ -95,11 +95,11 @@ module ApplicationTests
         end
       RUBY
 
-      text_template 'notifier/foo', <<-RUBY
+      text_template "notifier/foo", <<-RUBY
         Hello, World!
       RUBY
 
-      app_file 'lib/mailer_previews/notifier_preview.rb', <<-RUBY
+      app_file "lib/mailer_previews/notifier_preview.rb", <<-RUBY
         class NotifierPreview < ActionMailer::Preview
           def foo
             Notifier.foo
@@ -107,7 +107,7 @@ module ApplicationTests
         end
       RUBY
 
-      app('development')
+      app("development")
 
       get "/rails/mailers"
       assert_match '<h3><a href="/rails/mailers/notifier">Notifier</a></h3>', last_response.body
@@ -115,12 +115,12 @@ module ApplicationTests
     end
 
     test "mailer previews are reloaded across requests" do
-      app('development')
+      app("development")
 
       get "/rails/mailers"
       assert_no_match '<h3><a href="/rails/mailers/notifier">Notifier</a></h3>', last_response.body
 
-      mailer 'notifier', <<-RUBY
+      mailer "notifier", <<-RUBY
         class Notifier < ActionMailer::Base
           default from: "from@example.com"
 
@@ -130,11 +130,11 @@ module ApplicationTests
         end
       RUBY
 
-      text_template 'notifier/foo', <<-RUBY
+      text_template "notifier/foo", <<-RUBY
         Hello, World!
       RUBY
 
-      mailer_preview 'notifier', <<-RUBY
+      mailer_preview "notifier", <<-RUBY
         class NotifierPreview < ActionMailer::Preview
           def foo
             Notifier.foo
@@ -145,7 +145,7 @@ module ApplicationTests
       get "/rails/mailers"
       assert_match '<h3><a href="/rails/mailers/notifier">Notifier</a></h3>', last_response.body
 
-      remove_file 'test/mailers/previews/notifier_preview.rb'
+      remove_file "test/mailers/previews/notifier_preview.rb"
       sleep(1)
 
       get "/rails/mailers"
@@ -153,7 +153,7 @@ module ApplicationTests
     end
 
     test "mailer preview actions are added and removed" do
-      mailer 'notifier', <<-RUBY
+      mailer "notifier", <<-RUBY
         class Notifier < ActionMailer::Base
           default from: "from@example.com"
 
@@ -163,11 +163,11 @@ module ApplicationTests
         end
       RUBY
 
-      text_template 'notifier/foo', <<-RUBY
+      text_template "notifier/foo", <<-RUBY
         Hello, World!
       RUBY
 
-      mailer_preview 'notifier', <<-RUBY
+      mailer_preview "notifier", <<-RUBY
         class NotifierPreview < ActionMailer::Preview
           def foo
             Notifier.foo
@@ -175,14 +175,14 @@ module ApplicationTests
         end
       RUBY
 
-      app('development')
+      app("development")
 
       get "/rails/mailers"
       assert_match '<h3><a href="/rails/mailers/notifier">Notifier</a></h3>', last_response.body
       assert_match '<li><a href="/rails/mailers/notifier/foo">foo</a></li>', last_response.body
       assert_no_match '<li><a href="/rails/mailers/notifier/bar">bar</a></li>', last_response.body
 
-      mailer 'notifier', <<-RUBY
+      mailer "notifier", <<-RUBY
         class Notifier < ActionMailer::Base
           default from: "from@example.com"
 
@@ -196,15 +196,15 @@ module ApplicationTests
         end
       RUBY
 
-      text_template 'notifier/foo', <<-RUBY
+      text_template "notifier/foo", <<-RUBY
         Hello, World!
       RUBY
 
-      text_template 'notifier/bar', <<-RUBY
+      text_template "notifier/bar", <<-RUBY
         Goodbye, World!
       RUBY
 
-      mailer_preview 'notifier', <<-RUBY
+      mailer_preview "notifier", <<-RUBY
         class NotifierPreview < ActionMailer::Preview
           def foo
             Notifier.foo
@@ -223,7 +223,7 @@ module ApplicationTests
       assert_match '<li><a href="/rails/mailers/notifier/foo">foo</a></li>', last_response.body
       assert_match '<li><a href="/rails/mailers/notifier/bar">bar</a></li>', last_response.body
 
-      mailer 'notifier', <<-RUBY
+      mailer "notifier", <<-RUBY
         class Notifier < ActionMailer::Base
           default from: "from@example.com"
 
@@ -233,9 +233,9 @@ module ApplicationTests
         end
       RUBY
 
-      remove_file 'app/views/notifier/bar.text.erb'
+      remove_file "app/views/notifier/bar.text.erb"
 
-      mailer_preview 'notifier', <<-RUBY
+      mailer_preview "notifier", <<-RUBY
         class NotifierPreview < ActionMailer::Preview
           def foo
             Notifier.foo
@@ -254,12 +254,12 @@ module ApplicationTests
     test "mailer previews are reloaded from a custom preview_path" do
       add_to_config "config.action_mailer.preview_path = '#{app_path}/lib/mailer_previews'"
 
-      app('development')
+      app("development")
 
       get "/rails/mailers"
       assert_no_match '<h3><a href="/rails/mailers/notifier">Notifier</a></h3>', last_response.body
 
-      mailer 'notifier', <<-RUBY
+      mailer "notifier", <<-RUBY
         class Notifier < ActionMailer::Base
           default from: "from@example.com"
 
@@ -269,11 +269,11 @@ module ApplicationTests
         end
       RUBY
 
-      text_template 'notifier/foo', <<-RUBY
+      text_template "notifier/foo", <<-RUBY
         Hello, World!
       RUBY
 
-      app_file 'lib/mailer_previews/notifier_preview.rb', <<-RUBY
+      app_file "lib/mailer_previews/notifier_preview.rb", <<-RUBY
         class NotifierPreview < ActionMailer::Preview
           def foo
             Notifier.foo
@@ -284,7 +284,7 @@ module ApplicationTests
       get "/rails/mailers"
       assert_match '<h3><a href="/rails/mailers/notifier">Notifier</a></h3>', last_response.body
 
-      remove_file 'lib/mailer_previews/notifier_preview.rb'
+      remove_file "lib/mailer_previews/notifier_preview.rb"
       sleep(1)
 
       get "/rails/mailers"
@@ -292,14 +292,14 @@ module ApplicationTests
     end
 
     test "mailer preview not found" do
-      app('development')
+      app("development")
       get "/rails/mailers/notifier"
       assert last_response.not_found?
       assert_match "Mailer preview &#39;notifier&#39; not found", last_response.body
     end
 
     test "mailer preview email not found" do
-      mailer 'notifier', <<-RUBY
+      mailer "notifier", <<-RUBY
         class Notifier < ActionMailer::Base
           default from: "from@example.com"
 
@@ -309,11 +309,11 @@ module ApplicationTests
         end
       RUBY
 
-      text_template 'notifier/foo', <<-RUBY
+      text_template "notifier/foo", <<-RUBY
         Hello, World!
       RUBY
 
-      mailer_preview 'notifier', <<-RUBY
+      mailer_preview "notifier", <<-RUBY
         class NotifierPreview < ActionMailer::Preview
           def foo
             Notifier.foo
@@ -321,7 +321,7 @@ module ApplicationTests
         end
       RUBY
 
-      app('development')
+      app("development")
 
       get "/rails/mailers/notifier/bar"
       assert last_response.not_found?
@@ -329,7 +329,7 @@ module ApplicationTests
     end
 
     test "mailer preview NullMail" do
-      mailer 'notifier', <<-RUBY
+      mailer "notifier", <<-RUBY
         class Notifier < ActionMailer::Base
           default from: "from@example.com"
 
@@ -339,7 +339,7 @@ module ApplicationTests
         end
       RUBY
 
-      mailer_preview 'notifier', <<-RUBY
+      mailer_preview "notifier", <<-RUBY
         class NotifierPreview < ActionMailer::Preview
           def foo
             Notifier.foo
@@ -347,7 +347,7 @@ module ApplicationTests
         end
       RUBY
 
-      app('development')
+      app("development")
 
       get "/rails/mailers/notifier/foo"
       assert_match "You are trying to preview an email that does not have any content.", last_response.body
@@ -355,7 +355,7 @@ module ApplicationTests
     end
 
     test "mailer preview email part not found" do
-      mailer 'notifier', <<-RUBY
+      mailer "notifier", <<-RUBY
         class Notifier < ActionMailer::Base
           default from: "from@example.com"
 
@@ -365,11 +365,11 @@ module ApplicationTests
         end
       RUBY
 
-      text_template 'notifier/foo', <<-RUBY
+      text_template "notifier/foo", <<-RUBY
         Hello, World!
       RUBY
 
-      mailer_preview 'notifier', <<-RUBY
+      mailer_preview "notifier", <<-RUBY
         class NotifierPreview < ActionMailer::Preview
           def foo
             Notifier.foo
@@ -377,7 +377,7 @@ module ApplicationTests
         end
       RUBY
 
-      app('development')
+      app("development")
 
       get "/rails/mailers/notifier/foo?part=text%2Fhtml"
       assert last_response.not_found?
@@ -385,7 +385,7 @@ module ApplicationTests
     end
 
     test "message header uses full display names" do
-      mailer 'notifier', <<-RUBY
+      mailer "notifier", <<-RUBY
         class Notifier < ActionMailer::Base
           default from: "Ruby on Rails <core@rubyonrails.org>"
 
@@ -396,11 +396,11 @@ module ApplicationTests
         end
       RUBY
 
-      text_template 'notifier/foo', <<-RUBY
+      text_template "notifier/foo", <<-RUBY
         Hello, World!
       RUBY
 
-      mailer_preview 'notifier', <<-RUBY
+      mailer_preview "notifier", <<-RUBY
         class NotifierPreview < ActionMailer::Preview
           def foo
             Notifier.foo
@@ -408,7 +408,7 @@ module ApplicationTests
         end
       RUBY
 
-      app('development')
+      app("development")
 
       get "/rails/mailers/notifier/foo"
       assert_equal 200, last_response.status
@@ -418,7 +418,7 @@ module ApplicationTests
     end
 
     test "part menu selects correct option" do
-      mailer 'notifier', <<-RUBY
+      mailer "notifier", <<-RUBY
         class Notifier < ActionMailer::Base
           default from: "from@example.com"
 
@@ -428,15 +428,15 @@ module ApplicationTests
         end
       RUBY
 
-      html_template 'notifier/foo', <<-RUBY
+      html_template "notifier/foo", <<-RUBY
         <p>Hello, World!</p>
       RUBY
 
-      text_template 'notifier/foo', <<-RUBY
+      text_template "notifier/foo", <<-RUBY
         Hello, World!
       RUBY
 
-      mailer_preview 'notifier', <<-RUBY
+      mailer_preview "notifier", <<-RUBY
         class NotifierPreview < ActionMailer::Preview
           def foo
             Notifier.foo
@@ -444,7 +444,7 @@ module ApplicationTests
         end
       RUBY
 
-      app('development')
+      app("development")
 
       get "/rails/mailers/notifier/foo.html"
       assert_equal 200, last_response.status
@@ -456,7 +456,7 @@ module ApplicationTests
     end
 
     test "mailer previews create correct links when loaded on a subdirectory" do
-      mailer 'notifier', <<-RUBY
+      mailer "notifier", <<-RUBY
         class Notifier < ActionMailer::Base
           default from: "from@example.com"
 
@@ -466,11 +466,11 @@ module ApplicationTests
         end
       RUBY
 
-      text_template 'notifier/foo', <<-RUBY
+      text_template "notifier/foo", <<-RUBY
         Hello, World!
       RUBY
 
-      mailer_preview 'notifier', <<-RUBY
+      mailer_preview "notifier", <<-RUBY
         class NotifierPreview < ActionMailer::Preview
           def foo
             Notifier.foo
@@ -478,9 +478,9 @@ module ApplicationTests
         end
       RUBY
 
-      app('development')
+      app("development")
 
-      get "/rails/mailers", {}, 'SCRIPT_NAME' => '/my_app'
+      get "/rails/mailers", {}, "SCRIPT_NAME" => "/my_app"
       assert_match '<h3><a href="/my_app/rails/mailers/notifier">Notifier</a></h3>', last_response.body
       assert_match '<li><a href="/my_app/rails/mailers/notifier/foo">foo</a></li>', last_response.body
     end
@@ -488,7 +488,7 @@ module ApplicationTests
     test "plain text mailer preview with attachment" do
       image_file "pixel.png", "iVBORw0KGgoAAAANSUhEUgAAAAEAAAABAQMAAAAl21bKAAAAA1BMVEWzIioca/JlAAAACklEQVQI12NgAAAAAgAB4iG8MwAAAABJRU5ErkJgggo="
 
-      mailer 'notifier', <<-RUBY
+      mailer "notifier", <<-RUBY
         class Notifier < ActionMailer::Base
           default from: "from@example.com"
 
@@ -499,11 +499,11 @@ module ApplicationTests
         end
       RUBY
 
-      text_template 'notifier/foo', <<-RUBY
+      text_template "notifier/foo", <<-RUBY
         Hello, World!
       RUBY
 
-      mailer_preview 'notifier', <<-RUBY
+      mailer_preview "notifier", <<-RUBY
         class NotifierPreview < ActionMailer::Preview
           def foo
             Notifier.foo
@@ -511,7 +511,7 @@ module ApplicationTests
         end
       RUBY
 
-      app('development')
+      app("development")
 
       get "/rails/mailers/notifier/foo"
       assert_equal 200, last_response.status
@@ -525,7 +525,7 @@ module ApplicationTests
     test "multipart mailer preview with attachment" do
       image_file "pixel.png", "iVBORw0KGgoAAAANSUhEUgAAAAEAAAABAQMAAAAl21bKAAAAA1BMVEWzIioca/JlAAAACklEQVQI12NgAAAAAgAB4iG8MwAAAABJRU5ErkJgggo="
 
-      mailer 'notifier', <<-RUBY
+      mailer "notifier", <<-RUBY
         class Notifier < ActionMailer::Base
           default from: "from@example.com"
 
@@ -536,15 +536,15 @@ module ApplicationTests
         end
       RUBY
 
-      text_template 'notifier/foo', <<-RUBY
+      text_template "notifier/foo", <<-RUBY
         Hello, World!
       RUBY
 
-      html_template 'notifier/foo', <<-RUBY
+      html_template "notifier/foo", <<-RUBY
         <p>Hello, World!</p>
       RUBY
 
-      mailer_preview 'notifier', <<-RUBY
+      mailer_preview "notifier", <<-RUBY
         class NotifierPreview < ActionMailer::Preview
           def foo
             Notifier.foo
@@ -552,7 +552,7 @@ module ApplicationTests
         end
       RUBY
 
-      app('development')
+      app("development")
 
       get "/rails/mailers/notifier/foo"
       assert_equal 200, last_response.status
@@ -570,7 +570,7 @@ module ApplicationTests
     test "multipart mailer preview with inline attachment" do
       image_file "pixel.png", "iVBORw0KGgoAAAANSUhEUgAAAAEAAAABAQMAAAAl21bKAAAAA1BMVEWzIioca/JlAAAACklEQVQI12NgAAAAAgAB4iG8MwAAAABJRU5ErkJgggo="
 
-      mailer 'notifier', <<-RUBY
+      mailer "notifier", <<-RUBY
         class Notifier < ActionMailer::Base
           default from: "from@example.com"
 
@@ -581,16 +581,16 @@ module ApplicationTests
         end
       RUBY
 
-      text_template 'notifier/foo', <<-RUBY
+      text_template "notifier/foo", <<-RUBY
         Hello, World!
       RUBY
 
-      html_template 'notifier/foo', <<-RUBY
+      html_template "notifier/foo", <<-RUBY
         <p>Hello, World!</p>
         <%= image_tag attachments['pixel.png'].url %>
       RUBY
 
-      mailer_preview 'notifier', <<-RUBY
+      mailer_preview "notifier", <<-RUBY
         class NotifierPreview < ActionMailer::Preview
           def foo
             Notifier.foo
@@ -598,7 +598,7 @@ module ApplicationTests
         end
       RUBY
 
-      app('development')
+      app("development")
 
       get "/rails/mailers/notifier/foo"
       assert_equal 200, last_response.status
@@ -615,7 +615,7 @@ module ApplicationTests
     end
 
     test "multipart mailer preview with attached email" do
-      mailer 'notifier', <<-RUBY
+      mailer "notifier", <<-RUBY
         class Notifier < ActionMailer::Base
           default from: "from@example.com"
 
@@ -640,15 +640,15 @@ module ApplicationTests
         end
       RUBY
 
-      text_template 'notifier/foo', <<-RUBY
+      text_template "notifier/foo", <<-RUBY
         Hello, World!
       RUBY
 
-      html_template 'notifier/foo', <<-RUBY
+      html_template "notifier/foo", <<-RUBY
         <p>Hello, World!</p>
       RUBY
 
-      mailer_preview 'notifier', <<-RUBY
+      mailer_preview "notifier", <<-RUBY
         class NotifierPreview < ActionMailer::Preview
           def foo
             Notifier.foo
@@ -656,7 +656,7 @@ module ApplicationTests
         end
       RUBY
 
-      app('development')
+      app("development")
 
       get "/rails/mailers/notifier/foo"
       assert_equal 200, last_response.status
@@ -694,7 +694,7 @@ module ApplicationTests
       end
 
       def image_file(name, contents)
-        app_file("public/images/#{name}", Base64.strict_decode64(contents), 'wb')
+        app_file("public/images/#{name}", Base64.strict_decode64(contents), "wb")
       end
   end
 end
diff --git a/railties/test/application/middleware/cache_test.rb b/railties/test/application/middleware/cache_test.rb
index 9802de4a60..be44aa774f 100644
--- a/railties/test/application/middleware/cache_test.rb
+++ b/railties/test/application/middleware/cache_test.rb
@@ -1,4 +1,4 @@
-require 'isolation/abstract_unit'
+require "isolation/abstract_unit"
 
 module ApplicationTests
   class CacheTest < ActiveSupport::TestCase
@@ -6,7 +6,7 @@ module ApplicationTests
 
     def setup
       build_app
-      require 'rack/test'
+      require "rack/test"
       extend Rack::Test::Methods
     end
 
@@ -43,7 +43,7 @@ module ApplicationTests
         end
       RUBY
 
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get ':controller(/:action)'
         end
@@ -65,12 +65,12 @@ module ApplicationTests
       app("development")
 
       get "/expires/expires_header"
-      assert_nil last_response.headers['X-Rack-Cache']
+      assert_nil last_response.headers["X-Rack-Cache"]
 
       body = last_response.body
 
       get "/expires/expires_header"
-      assert_nil last_response.headers['X-Rack-Cache']
+      assert_nil last_response.headers["X-Rack-Cache"]
       assert_not_equal body, last_response.body
     end
 
diff --git a/railties/test/application/middleware/cookies_test.rb b/railties/test/application/middleware/cookies_test.rb
index 7a1a0083b1..1e4b5d086c 100644
--- a/railties/test/application/middleware/cookies_test.rb
+++ b/railties/test/application/middleware/cookies_test.rb
@@ -1,4 +1,4 @@
-require 'isolation/abstract_unit'
+require "isolation/abstract_unit"
 
 module ApplicationTests
   class CookiesTest < ActiveSupport::TestCase
@@ -18,27 +18,27 @@ module ApplicationTests
       FileUtils.rm_rf(new_app) if File.directory?(new_app)
     end
 
-    test 'always_write_cookie is true by default in development' do
-      require 'rails'
-      Rails.env = 'development'
+    test "always_write_cookie is true by default in development" do
+      require "rails"
+      Rails.env = "development"
       require "#{app_path}/config/environment"
       assert_equal true, ActionDispatch::Cookies::CookieJar.always_write_cookie
     end
 
-    test 'always_write_cookie is false by default in production' do
-      require 'rails'
-      Rails.env = 'production'
+    test "always_write_cookie is false by default in production" do
+      require "rails"
+      Rails.env = "production"
       require "#{app_path}/config/environment"
       assert_equal false, ActionDispatch::Cookies::CookieJar.always_write_cookie
     end
 
-    test 'always_write_cookie can be overridden' do
+    test "always_write_cookie can be overridden" do
       add_to_config <<-RUBY
         config.action_dispatch.always_write_cookie = false
       RUBY
 
-      require 'rails'
-      Rails.env = 'development'
+      require "rails"
+      Rails.env = "development"
       require "#{app_path}/config/environment"
       assert_equal false, ActionDispatch::Cookies::CookieJar.always_write_cookie
     end
diff --git a/railties/test/application/middleware/exceptions_test.rb b/railties/test/application/middleware/exceptions_test.rb
index 44c0215341..fcc22cc813 100644
--- a/railties/test/application/middleware/exceptions_test.rb
+++ b/railties/test/application/middleware/exceptions_test.rb
@@ -1,5 +1,5 @@
-require 'isolation/abstract_unit'
-require 'rack/test'
+require "isolation/abstract_unit"
+require "rack/test"
 
 module ApplicationTests
   class MiddlewareExceptionsTest < ActiveSupport::TestCase
@@ -69,7 +69,7 @@ module ApplicationTests
 
       app.config.action_dispatch.show_exceptions = true
 
-      get '/foo'
+      get "/foo"
       assert_equal 500, last_response.status
     end
 
@@ -77,7 +77,7 @@ module ApplicationTests
       app.config.action_dispatch.show_exceptions = false
 
       assert_raise(ActionController::RoutingError) do
-        get '/foo'
+        get "/foo"
       end
     end
 
@@ -85,7 +85,7 @@ module ApplicationTests
       app.config.action_dispatch.show_exceptions = true
 
       assert_nothing_raised do
-        get '/foo'
+        get "/foo"
         assert_match "The page you were looking for doesn't exist.", last_response.body
       end
     end
@@ -95,7 +95,7 @@ module ApplicationTests
       app.config.consider_all_requests_local = true
 
       assert_nothing_raised do
-        get '/foo'
+        get "/foo"
         assert_match "No route matches", last_response.body
       end
     end
@@ -111,12 +111,12 @@ module ApplicationTests
       app.config.action_dispatch.show_exceptions = true
       app.config.consider_all_requests_local = true
 
-      app_file 'app/views/foo/index.html.erb', <<-ERB
+      app_file "app/views/foo/index.html.erb", <<-ERB
         <% raise 'boooom' %>
         ✓測試テスト시험
       ERB
 
-      get '/foo', :utf8 => '✓'
+      get "/foo", :utf8 => "✓"
       assert_match(/boooom/, last_response.body)
       assert_match(/測試テスト시험/, last_response.body)
     end
diff --git a/railties/test/application/middleware/remote_ip_test.rb b/railties/test/application/middleware/remote_ip_test.rb
index 37bd8a25c1..c34d9d6ee7 100644
--- a/railties/test/application/middleware/remote_ip_test.rb
+++ b/railties/test/application/middleware/remote_ip_test.rb
@@ -1,6 +1,6 @@
-require 'ipaddr'
-require 'isolation/abstract_unit'
-require 'active_support/key_generator'
+require "ipaddr"
+require "isolation/abstract_unit"
+require "active_support/key_generator"
 
 module ApplicationTests
   class RemoteIpTest < ActiveSupport::TestCase
@@ -9,8 +9,8 @@ module ApplicationTests
     def remote_ip(env = {})
       remote_ip = nil
       env = Rack::MockRequest.env_for("/").merge(env).merge!(
-        'action_dispatch.show_exceptions' => false,
-        'action_dispatch.key_generator'   => ActiveSupport::LegacyKeyGenerator.new('b3c631c314c0bbca50c1b2843150fe33')
+        "action_dispatch.show_exceptions" => false,
+        "action_dispatch.key_generator"   => ActiveSupport::LegacyKeyGenerator.new("b3c631c314c0bbca50c1b2843150fe33")
       )
 
       endpoint = Proc.new do |e|
@@ -69,7 +69,7 @@ module ApplicationTests
 
     test "the user can set trusted proxies with an IPAddr argument" do
       make_basic_app do |app|
-        app.config.action_dispatch.trusted_proxies = IPAddr.new('4.2.42.0/24')
+        app.config.action_dispatch.trusted_proxies = IPAddr.new("4.2.42.0/24")
       end
 
       assert_equal "1.1.1.1", remote_ip("REMOTE_ADDR" => "1.1.1.1", "HTTP_X_FORWARDED_FOR" => "10.0.0.0,4.2.42.42")
diff --git a/railties/test/application/middleware/sendfile_test.rb b/railties/test/application/middleware/sendfile_test.rb
index 18e23ca17b..4938402fdc 100644
--- a/railties/test/application/middleware/sendfile_test.rb
+++ b/railties/test/application/middleware/sendfile_test.rb
@@ -1,4 +1,4 @@
-require 'isolation/abstract_unit'
+require "isolation/abstract_unit"
 
 module ApplicationTests
   class SendfileTest < ActiveSupport::TestCase
@@ -48,7 +48,7 @@ module ApplicationTests
 
     test "config.action_dispatch.x_sendfile_header is sent to Rack::Sendfile" do
       make_basic_app do |app|
-        app.config.action_dispatch.x_sendfile_header = 'X-Lighttpd-Send-File'
+        app.config.action_dispatch.x_sendfile_header = "X-Lighttpd-Send-File"
       end
 
       simple_controller
@@ -59,7 +59,7 @@ module ApplicationTests
 
     test "files handled by ActionDispatch::Static are handled by Rack::Sendfile" do
       make_basic_app do |app|
-        app.config.action_dispatch.x_sendfile_header = 'X-Sendfile'
+        app.config.action_dispatch.x_sendfile_header = "X-Sendfile"
         app.config.public_file_server.enabled = true
         app.paths["public"] = File.join(rails_root, "public")
       end
diff --git a/railties/test/application/middleware/session_test.rb b/railties/test/application/middleware/session_test.rb
index 64cae27ea2..2873425703 100644
--- a/railties/test/application/middleware/session_test.rb
+++ b/railties/test/application/middleware/session_test.rb
@@ -1,5 +1,5 @@
-require 'isolation/abstract_unit'
-require 'rack/test'
+require "isolation/abstract_unit"
+require "rack/test"
 
 module ApplicationTests
   class MiddlewareSessionTest < ActiveSupport::TestCase
@@ -53,7 +53,7 @@ module ApplicationTests
     end
 
     test "session is empty and isn't saved on unverified request when using :null_session protect method" do
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get  ':controller(/:action)'
           post ':controller(/:action)'
@@ -81,20 +81,20 @@ module ApplicationTests
 
       require "#{app_path}/config/environment"
 
-      get '/foo/write_session'
-      get '/foo/read_session'
-      assert_equal '1', last_response.body
+      get "/foo/write_session"
+      get "/foo/read_session"
+      assert_equal "1", last_response.body
 
-      post '/foo/read_session'               # Read session using POST request without CSRF token
-      assert_equal 'nil', last_response.body # Stored value shouldn't be accessible
+      post "/foo/read_session"               # Read session using POST request without CSRF token
+      assert_equal "nil", last_response.body # Stored value shouldn't be accessible
 
-      post '/foo/write_session' # Write session using POST request without CSRF token
-      get '/foo/read_session'   # Session shouldn't be changed
-      assert_equal '1', last_response.body
+      post "/foo/write_session" # Write session using POST request without CSRF token
+      get "/foo/read_session"   # Session shouldn't be changed
+      assert_equal "1", last_response.body
     end
 
     test "cookie jar is empty and isn't saved on unverified request when using :null_session protect method" do
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get  ':controller(/:action)'
           post ':controller(/:action)'
@@ -122,20 +122,20 @@ module ApplicationTests
 
       require "#{app_path}/config/environment"
 
-      get '/foo/write_cookie'
-      get '/foo/read_cookie'
+      get "/foo/write_cookie"
+      get "/foo/read_cookie"
       assert_equal '"1"', last_response.body
 
-      post '/foo/read_cookie'                # Read cookie using POST request without CSRF token
-      assert_equal 'nil', last_response.body # Stored value shouldn't be accessible
+      post "/foo/read_cookie"                # Read cookie using POST request without CSRF token
+      assert_equal "nil", last_response.body # Stored value shouldn't be accessible
 
-      post '/foo/write_cookie' # Write cookie using POST request without CSRF token
-      get '/foo/read_cookie'   # Cookie shouldn't be changed
+      post "/foo/write_cookie" # Write cookie using POST request without CSRF token
+      get "/foo/read_cookie"   # Cookie shouldn't be changed
       assert_equal '"1"', last_response.body
     end
 
     test "session using encrypted cookie store" do
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get ':controller(/:action)'
         end
@@ -164,23 +164,23 @@ module ApplicationTests
 
       require "#{app_path}/config/environment"
 
-      get '/foo/write_session'
-      get '/foo/read_session'
-      assert_equal '1', last_response.body
+      get "/foo/write_session"
+      get "/foo/read_session"
+      assert_equal "1", last_response.body
 
-      get '/foo/read_encrypted_cookie'
-      assert_equal '1', last_response.body
+      get "/foo/read_encrypted_cookie"
+      assert_equal "1", last_response.body
 
-      secret = app.key_generator.generate_key('encrypted cookie')
-      sign_secret = app.key_generator.generate_key('signed encrypted cookie')
+      secret = app.key_generator.generate_key("encrypted cookie")
+      sign_secret = app.key_generator.generate_key("signed encrypted cookie")
       encryptor = ActiveSupport::MessageEncryptor.new(secret, sign_secret)
 
-      get '/foo/read_raw_cookie'
-      assert_equal 1, encryptor.decrypt_and_verify(last_response.body)['foo']
+      get "/foo/read_raw_cookie"
+      assert_equal 1, encryptor.decrypt_and_verify(last_response.body)["foo"]
     end
 
     test "session upgrading signature to encryption cookie store works the same way as encrypted cookie store" do
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get ':controller(/:action)'
         end
@@ -213,23 +213,23 @@ module ApplicationTests
 
       require "#{app_path}/config/environment"
 
-      get '/foo/write_session'
-      get '/foo/read_session'
-      assert_equal '1', last_response.body
+      get "/foo/write_session"
+      get "/foo/read_session"
+      assert_equal "1", last_response.body
 
-      get '/foo/read_encrypted_cookie'
-      assert_equal '1', last_response.body
+      get "/foo/read_encrypted_cookie"
+      assert_equal "1", last_response.body
 
-      secret = app.key_generator.generate_key('encrypted cookie')
-      sign_secret = app.key_generator.generate_key('signed encrypted cookie')
+      secret = app.key_generator.generate_key("encrypted cookie")
+      sign_secret = app.key_generator.generate_key("signed encrypted cookie")
       encryptor = ActiveSupport::MessageEncryptor.new(secret, sign_secret)
 
-      get '/foo/read_raw_cookie'
-      assert_equal 1, encryptor.decrypt_and_verify(last_response.body)['foo']
+      get "/foo/read_raw_cookie"
+      assert_equal 1, encryptor.decrypt_and_verify(last_response.body)["foo"]
     end
 
     test "session upgrading signature to encryption cookie store upgrades session to encrypted mode" do
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get ':controller(/:action)'
         end
@@ -268,27 +268,27 @@ module ApplicationTests
 
       require "#{app_path}/config/environment"
 
-      get '/foo/write_raw_session'
-      get '/foo/read_session'
-      assert_equal '1', last_response.body
+      get "/foo/write_raw_session"
+      get "/foo/read_session"
+      assert_equal "1", last_response.body
 
-      get '/foo/write_session'
-      get '/foo/read_session'
-      assert_equal '2', last_response.body
+      get "/foo/write_session"
+      get "/foo/read_session"
+      assert_equal "2", last_response.body
 
-      get '/foo/read_encrypted_cookie'
-      assert_equal '2', last_response.body
+      get "/foo/read_encrypted_cookie"
+      assert_equal "2", last_response.body
 
-      secret = app.key_generator.generate_key('encrypted cookie')
-      sign_secret = app.key_generator.generate_key('signed encrypted cookie')
+      secret = app.key_generator.generate_key("encrypted cookie")
+      sign_secret = app.key_generator.generate_key("signed encrypted cookie")
       encryptor = ActiveSupport::MessageEncryptor.new(secret, sign_secret)
 
-      get '/foo/read_raw_cookie'
-      assert_equal 2, encryptor.decrypt_and_verify(last_response.body)['foo']
+      get "/foo/read_raw_cookie"
+      assert_equal 2, encryptor.decrypt_and_verify(last_response.body)["foo"]
     end
 
     test "session upgrading legacy signed cookies to new signed cookies" do
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get ':controller(/:action)'
         end
@@ -328,25 +328,25 @@ module ApplicationTests
 
       require "#{app_path}/config/environment"
 
-      get '/foo/write_raw_session'
-      get '/foo/read_session'
-      assert_equal '1', last_response.body
+      get "/foo/write_raw_session"
+      get "/foo/read_session"
+      assert_equal "1", last_response.body
 
-      get '/foo/write_session'
-      get '/foo/read_session'
-      assert_equal '2', last_response.body
+      get "/foo/write_session"
+      get "/foo/read_session"
+      assert_equal "2", last_response.body
 
-      get '/foo/read_signed_cookie'
-      assert_equal '2', last_response.body
+      get "/foo/read_signed_cookie"
+      assert_equal "2", last_response.body
 
       verifier = ActiveSupport::MessageVerifier.new(app.secrets.secret_token)
 
-      get '/foo/read_raw_cookie'
-      assert_equal 2, verifier.verify(last_response.body)['foo']
+      get "/foo/read_raw_cookie"
+      assert_equal 2, verifier.verify(last_response.body)["foo"]
     end
 
-    test 'calling reset_session on request does not trigger an error for API apps' do
-      add_to_config 'config.api_only = true'
+    test "calling reset_session on request does not trigger an error for API apps" do
+      add_to_config "config.api_only = true"
 
       controller :test, <<-RUBY
         class TestController < ApplicationController
@@ -357,7 +357,7 @@ module ApplicationTests
         end
       RUBY
 
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get '/dump_flash' => "test#dump_flash"
         end
@@ -365,10 +365,10 @@ module ApplicationTests
 
       require "#{app_path}/config/environment"
 
-      get '/dump_flash'
+      get "/dump_flash"
 
       assert_equal 200, last_response.status
-      assert_equal 'It worked!', last_response.body
+      assert_equal "It worked!", last_response.body
 
       refute Rails.application.middleware.include?(ActionDispatch::Flash)
     end
diff --git a/railties/test/application/middleware/static_test.rb b/railties/test/application/middleware/static_test.rb
index 1246e20d94..8a06e91297 100644
--- a/railties/test/application/middleware/static_test.rb
+++ b/railties/test/application/middleware/static_test.rb
@@ -1,5 +1,5 @@
-require 'isolation/abstract_unit'
-require 'rack/test'
+require "isolation/abstract_unit"
+require "rack/test"
 
 module ApplicationTests
   class MiddlewareStaticTest < ActiveSupport::TestCase
@@ -18,17 +18,17 @@ module ApplicationTests
     # Regression test to #8907
     # See https://github.com/rails/rails/commit/9cc82b77196d21a5c7021f6dca59ab9b2b158a45#commitcomment-2416514
     test "doesn't set Cache-Control header when it is nil" do
-      app_file "public/foo.html", 'static'
+      app_file "public/foo.html", "static"
 
       require "#{app_path}/config/environment"
 
-      get 'foo'
+      get "foo"
 
-      assert_not last_response.headers.has_key?('Cache-Control'), "Cache-Control should not be set"
+      assert_not last_response.headers.has_key?("Cache-Control"), "Cache-Control should not be set"
     end
 
     test "headers for static files are configurable" do
-      app_file "public/about.html", 'static'
+      app_file "public/about.html", "static"
       add_to_config <<-CONFIG
         config.public_file_server.headers = {
           "Access-Control-Allow-Origin" => "http://rubyonrails.org",
@@ -38,10 +38,10 @@ module ApplicationTests
 
       require "#{app_path}/config/environment"
 
-      get '/about.html'
+      get "/about.html"
 
-      assert_equal 'http://rubyonrails.org', last_response.headers["Access-Control-Allow-Origin"]
-      assert_equal 'public, max-age=60',     last_response.headers["Cache-Control"]
+      assert_equal "http://rubyonrails.org", last_response.headers["Access-Control-Allow-Origin"]
+      assert_equal "public, max-age=60",     last_response.headers["Cache-Control"]
     end
 
     test "public_file_server.index_name defaults to 'index'" do
@@ -49,7 +49,7 @@ module ApplicationTests
       
       require "#{app_path}/config/environment"
 
-      get '/'
+      get "/"
       
       assert_equal "/index.html\n", last_response.body
     end
@@ -60,7 +60,7 @@ module ApplicationTests
 
       require "#{app_path}/config/environment"
 
-      get '/'
+      get "/"
 
       assert_equal "/other-index.html\n", last_response.body
     end
diff --git a/railties/test/application/middleware_test.rb b/railties/test/application/middleware_test.rb
index 23699cae74..3b48ada190 100644
--- a/railties/test/application/middleware_test.rb
+++ b/railties/test/application/middleware_test.rb
@@ -1,4 +1,4 @@
-require 'isolation/abstract_unit'
+require "isolation/abstract_unit"
 
 module ApplicationTests
   class MiddlewareTest < ActiveSupport::TestCase
@@ -103,7 +103,7 @@ module ApplicationTests
       add_to_config "config.ssl_options = { host: 'example.com' }"
       boot!
 
-      assert_equal [{host: 'example.com'}], Rails.application.middleware.first.args
+      assert_equal [{host: "example.com"}], Rails.application.middleware.first.args
     end
 
     test "removing Active Record omits its middleware" do
@@ -190,10 +190,10 @@ module ApplicationTests
       assert_equal "Rack::Config", middleware.second
     end
 
-    test 'unshift middleware' do
-      add_to_config 'config.middleware.unshift Rack::Config'
+    test "unshift middleware" do
+      add_to_config "config.middleware.unshift Rack::Config"
       boot!
-      assert_equal 'Rack::Config', middleware.first
+      assert_equal "Rack::Config", middleware.first
     end
 
     test "Rails.cache does not respond to middleware" do
diff --git a/railties/test/application/multiple_applications_test.rb b/railties/test/application/multiple_applications_test.rb
index f9628fe5a8..26b810af73 100644
--- a/railties/test/application/multiple_applications_test.rb
+++ b/railties/test/application/multiple_applications_test.rb
@@ -1,4 +1,4 @@
-require 'isolation/abstract_unit'
+require "isolation/abstract_unit"
 
 module ApplicationTests
   class MultipleApplicationsTest < ActiveSupport::TestCase
@@ -7,7 +7,7 @@ module ApplicationTests
     def setup
       build_app(initializers: true)
       require "#{rails_root}/config/environment"
-      Rails.application.config.some_setting = 'something_or_other'
+      Rails.application.config.some_setting = "something_or_other"
     end
 
     def teardown
@@ -87,9 +87,9 @@ module ApplicationTests
       require "#{app_path}/config/environment"
 
       assert_equal 0, run_count, "The count should stay at zero without any calls to the rake tasks"
-      require 'rake'
-      require 'rake/testtask'
-      require 'rdoc/task'
+      require "rake"
+      require "rake/testtask"
+      require "rdoc/task"
       Rails.application.load_tasks
       assert_equal 2, run_count, "Calling a rake task should result in two increments to the count"
     end
diff --git a/railties/test/application/per_request_digest_cache_test.rb b/railties/test/application/per_request_digest_cache_test.rb
index dfe3fc9354..6c003e9bcc 100644
--- a/railties/test/application/per_request_digest_cache_test.rb
+++ b/railties/test/application/per_request_digest_cache_test.rb
@@ -1,9 +1,9 @@
-require 'isolation/abstract_unit'
-require 'rack/test'
-require 'minitest/mock'
+require "isolation/abstract_unit"
+require "rack/test"
+require "minitest/mock"
 
-require 'action_view'
-require 'active_support/testing/method_call_assertions'
+require "action_view"
+require "active_support/testing/method_call_assertions"
 
 class PerRequestDigestCacheTest < ActiveSupport::TestCase
   include ActiveSupport::Testing::Isolation
@@ -12,22 +12,22 @@ class PerRequestDigestCacheTest < ActiveSupport::TestCase
 
   setup do
     build_app
-    add_to_config 'config.consider_all_requests_local = true'
+    add_to_config "config.consider_all_requests_local = true"
 
-    app_file 'app/models/customer.rb', <<-RUBY
+    app_file "app/models/customer.rb", <<-RUBY
       class Customer < Struct.new(:name, :id)
         extend ActiveModel::Naming
         include ActiveModel::Conversion
       end
     RUBY
 
-    app_file 'config/routes.rb', <<-RUBY
+    app_file "config/routes.rb", <<-RUBY
       Rails.application.routes.draw do
         resources :customers, only: :index
       end
     RUBY
 
-    app_file 'app/controllers/customers_controller.rb', <<-RUBY
+    app_file "app/controllers/customers_controller.rb", <<-RUBY
       class CustomersController < ApplicationController
         self.perform_caching = true
 
@@ -37,7 +37,7 @@ class PerRequestDigestCacheTest < ActiveSupport::TestCase
       end
     RUBY
 
-    app_file 'app/views/customers/_customer.html.erb', <<-RUBY
+    app_file "app/views/customers/_customer.html.erb", <<-RUBY
       <% cache customer do %>
         <%= customer.name %>
       <% end %>
@@ -49,17 +49,17 @@ class PerRequestDigestCacheTest < ActiveSupport::TestCase
   teardown :teardown_app
 
   test "digests are reused when rendering the same template twice" do
-    get '/customers'
+    get "/customers"
     assert_equal 200, last_response.status
 
     values = ActionView::LookupContext::DetailsKey.digest_caches.first.values
-    assert_equal [ '8ba099b7749542fe765ff34a6824d548' ], values
+    assert_equal [ "8ba099b7749542fe765ff34a6824d548" ], values
     assert_equal %w(david dingus), last_response.body.split.map(&:strip)
   end
 
   test "template digests are cleared before a request" do
     assert_called(ActionView::LookupContext::DetailsKey, :clear) do
-      get '/customers'
+      get "/customers"
       assert_equal 200, last_response.status
     end
   end
diff --git a/railties/test/application/rack/logger_test.rb b/railties/test/application/rack/logger_test.rb
index 0082ec9cd2..e71bcbc536 100644
--- a/railties/test/application/rack/logger_test.rb
+++ b/railties/test/application/rack/logger_test.rb
@@ -41,13 +41,13 @@ module ApplicationTests
       end
 
       test "logger logs HTTP verb override" do
-        post "/", _method: 'put'
+        post "/", _method: "put"
         wait
         assert_match 'Started PUT "/"', logs
       end
 
       test "logger logs HEAD requests" do
-        post "/", _method: 'head'
+        post "/", _method: "head"
         wait
         assert_match 'Started HEAD "/"', logs
       end
diff --git a/railties/test/application/rackup_test.rb b/railties/test/application/rackup_test.rb
index 4aef9b299c..2943e9ee5d 100644
--- a/railties/test/application/rackup_test.rb
+++ b/railties/test/application/rackup_test.rb
@@ -36,7 +36,7 @@ module ApplicationTests
 
     test "the config object is available on the application object" do
       rackup
-      assert_equal 'UTC', Rails.application.config.time_zone
+      assert_equal "UTC", Rails.application.config.time_zone
     end
   end
 end
diff --git a/railties/test/application/rake/dbs_test.rb b/railties/test/application/rake/dbs_test.rb
index f9bf670c5a..51db634b75 100644
--- a/railties/test/application/rake/dbs_test.rb
+++ b/railties/test/application/rake/dbs_test.rb
@@ -20,7 +20,7 @@ module ApplicationTests
       end
 
       def set_database_url
-        ENV['DATABASE_URL'] = "sqlite3:#{database_url_db_name}"
+        ENV["DATABASE_URL"] = "sqlite3:#{database_url_db_name}"
         # ensure it's using the DATABASE_URL
         FileUtils.rm_rf("#{app_path}/config/database.yml")
       end
@@ -37,12 +37,12 @@ module ApplicationTests
         end
       end
 
-      test 'db:create and db:drop without database url' do
+      test "db:create and db:drop without database url" do
         require "#{app_path}/config/environment"
-        db_create_and_drop ActiveRecord::Base.configurations[Rails.env]['database']
+        db_create_and_drop ActiveRecord::Base.configurations[Rails.env]["database"]
       end
 
-      test 'db:create and db:drop with database url' do
+      test "db:create and db:drop with database url" do
         require "#{app_path}/config/environment"
         set_database_url
         db_create_and_drop database_url_db_name
@@ -57,7 +57,7 @@ module ApplicationTests
         end
       end
 
-      test 'db:create failure because database exists' do
+      test "db:create failure because database exists" do
         with_database_existing do
           output = `bin/rails db:create 2>&1`
           assert_match(/already exists/, output)
@@ -74,7 +74,7 @@ module ApplicationTests
         end
       end
 
-      test 'db:create failure because bad permissions' do
+      test "db:create failure because bad permissions" do
         with_bad_permissions do
           output = `bin/rails db:create 2>&1`
           assert_match(/Couldn't create database/, output)
@@ -82,7 +82,7 @@ module ApplicationTests
         end
       end
 
-      test 'db:drop failure because database does not exist' do
+      test "db:drop failure because database does not exist" do
         Dir.chdir(app_path) do
           output = `bin/rails db:drop:_unsafe --trace 2>&1`
           assert_match(/does not exist/, output)
@@ -90,7 +90,7 @@ module ApplicationTests
         end
       end
 
-      test 'db:drop failure because bad permissions' do
+      test "db:drop failure because bad permissions" do
         with_database_existing do
           with_bad_permissions do
             output = `bin/rails db:drop 2>&1`
@@ -110,12 +110,12 @@ module ApplicationTests
         end
       end
 
-      test 'db:migrate and db:migrate:status without database_url' do
+      test "db:migrate and db:migrate:status without database_url" do
         require "#{app_path}/config/environment"
-        db_migrate_and_status ActiveRecord::Base.configurations[Rails.env]['database']
+        db_migrate_and_status ActiveRecord::Base.configurations[Rails.env]["database"]
       end
 
-      test 'db:migrate and db:migrate:status with database_url' do
+      test "db:migrate and db:migrate:status with database_url" do
         require "#{app_path}/config/environment"
         set_database_url
         db_migrate_and_status database_url_db_name
@@ -130,11 +130,11 @@ module ApplicationTests
         end
       end
 
-      test 'db:schema:dump without database_url' do
+      test "db:schema:dump without database_url" do
         db_schema_dump
       end
 
-      test 'db:schema:dump with database_url' do
+      test "db:schema:dump with database_url" do
         set_database_url
         db_schema_dump
       end
@@ -149,18 +149,18 @@ module ApplicationTests
         end
       end
 
-      test 'db:fixtures:load without database_url' do
+      test "db:fixtures:load without database_url" do
         require "#{app_path}/config/environment"
-        db_fixtures_load ActiveRecord::Base.configurations[Rails.env]['database']
+        db_fixtures_load ActiveRecord::Base.configurations[Rails.env]["database"]
       end
 
-      test 'db:fixtures:load with database_url' do
+      test "db:fixtures:load with database_url" do
         require "#{app_path}/config/environment"
         set_database_url
         db_fixtures_load database_url_db_name
       end
 
-      test 'db:fixtures:load with namespaced fixture' do
+      test "db:fixtures:load with namespaced fixture" do
         require "#{app_path}/config/environment"
         Dir.chdir(app_path) do
           `bin/rails generate model admin::book title:string;
@@ -184,18 +184,18 @@ module ApplicationTests
         end
       end
 
-      test 'db:structure:dump and db:structure:load without database_url' do
+      test "db:structure:dump and db:structure:load without database_url" do
         require "#{app_path}/config/environment"
-        db_structure_dump_and_load ActiveRecord::Base.configurations[Rails.env]['database']
+        db_structure_dump_and_load ActiveRecord::Base.configurations[Rails.env]["database"]
       end
 
-      test 'db:structure:dump and db:structure:load with database_url' do
+      test "db:structure:dump and db:structure:load with database_url" do
         require "#{app_path}/config/environment"
         set_database_url
         db_structure_dump_and_load database_url_db_name
       end
 
-      test 'db:structure:dump does not dump schema information when no migrations are used' do
+      test "db:structure:dump does not dump schema information when no migrations are used" do
         Dir.chdir(app_path) do
           # create table without migrations
           `bin/rails runner 'ActiveRecord::Base.connection.create_table(:posts) {|t| t.string :title }'`
@@ -207,11 +207,11 @@ module ApplicationTests
         end
       end
 
-      test 'db:schema:load and db:structure:load do not purge the existing database' do
+      test "db:schema:load and db:structure:load do not purge the existing database" do
         Dir.chdir(app_path) do
           `bin/rails runner 'ActiveRecord::Base.connection.create_table(:posts) {|t| t.string :title }'`
 
-          app_file 'db/schema.rb', <<-RUBY
+          app_file "db/schema.rb", <<-RUBY
             ActiveRecord::Schema.define(version: 20140423102712) do
               create_table(:comments) {}
             end
@@ -223,7 +223,7 @@ module ApplicationTests
           `bin/rails db:schema:load`
           assert_equal '["posts", "comments", "schema_migrations", "ar_internal_metadata"]', list_tables[]
 
-          app_file 'db/structure.sql', <<-SQL
+          app_file "db/structure.sql", <<-SQL
             CREATE TABLE "users" ("id" INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, "name" varchar(255));
           SQL
 
@@ -234,15 +234,15 @@ module ApplicationTests
 
       test "db:schema:load with inflections" do
         Dir.chdir(app_path) do
-          app_file 'config/initializers/inflection.rb', <<-RUBY
+          app_file "config/initializers/inflection.rb", <<-RUBY
             ActiveSupport::Inflector.inflections do |inflect|
               inflect.irregular 'goose', 'geese'
             end
           RUBY
-          app_file 'config/initializers/primary_key_table_name.rb', <<-RUBY
+          app_file "config/initializers/primary_key_table_name.rb", <<-RUBY
             ActiveRecord::Base.primary_key_prefix_type = :table_name
           RUBY
-          app_file 'db/schema.rb', <<-RUBY
+          app_file "db/schema.rb", <<-RUBY
             ActiveRecord::Schema.define(version: 20140423102712) do
               create_table("goose".pluralize) do |t|
                 t.string :name
@@ -269,24 +269,24 @@ module ApplicationTests
           require "#{app_path}/app/models/book"
           #if structure is not loaded correctly, exception would be raised
           assert_equal 0, Book.count
-          assert_match ActiveRecord::Base.configurations['test']['database'],
+          assert_match ActiveRecord::Base.configurations["test"]["database"],
             ActiveRecord::Base.connection_config[:database]
         end
       end
 
-      test 'db:test:load_structure without database_url' do
+      test "db:test:load_structure without database_url" do
         require "#{app_path}/config/environment"
         db_test_load_structure
       end
 
-      test 'db:setup loads schema and seeds database' do
+      test "db:setup loads schema and seeds database" do
         begin
           @old_rails_env = ENV["RAILS_ENV"]
           @old_rack_env = ENV["RACK_ENV"]
           ENV.delete "RAILS_ENV"
           ENV.delete "RACK_ENV"
 
-          app_file 'db/schema.rb', <<-RUBY
+          app_file "db/schema.rb", <<-RUBY
             ActiveRecord::Schema.define(version: "1") do
               create_table :users do |t|
                 t.string :name
@@ -294,7 +294,7 @@ module ApplicationTests
             end
           RUBY
 
-          app_file 'db/seeds.rb', <<-RUBY
+          app_file "db/seeds.rb", <<-RUBY
             puts ActiveRecord::Base.connection_config[:database]
           RUBY
 
diff --git a/railties/test/application/rake/dev_test.rb b/railties/test/application/rake/dev_test.rb
index 2330ad3535..4f992d9c8d 100644
--- a/railties/test/application/rake/dev_test.rb
+++ b/railties/test/application/rake/dev_test.rb
@@ -1,4 +1,4 @@
-require 'isolation/abstract_unit'
+require "isolation/abstract_unit"
 
 module ApplicationTests
   module RakeTests
@@ -13,24 +13,24 @@ module ApplicationTests
         teardown_app
       end
 
-      test 'dev:cache creates file and outputs message' do
+      test "dev:cache creates file and outputs message" do
         Dir.chdir(app_path) do
           output = `rails dev:cache`
-          assert File.exist?('tmp/caching-dev.txt')
+          assert File.exist?("tmp/caching-dev.txt")
           assert_match(/Development mode is now being cached/, output)
         end
       end
 
-      test 'dev:cache deletes file and outputs message' do
+      test "dev:cache deletes file and outputs message" do
         Dir.chdir(app_path) do
           `rails dev:cache` # Create caching file.
           output = `rails dev:cache` # Delete caching file.
-          assert_not File.exist?('tmp/caching-dev.txt')
+          assert_not File.exist?("tmp/caching-dev.txt")
           assert_match(/Development mode is no longer being cached/, output)
         end
       end
 
-      test 'dev:cache removes server.pid also' do
+      test "dev:cache removes server.pid also" do
         Dir.chdir(app_path) do
           FileUtils.mkdir_p("tmp/pids")
           FileUtils.touch("tmp/pids/server.pid")
diff --git a/railties/test/application/rake/framework_test.rb b/railties/test/application/rake/framework_test.rb
index 04e54b2c70..7ac37b7700 100644
--- a/railties/test/application/rake/framework_test.rb
+++ b/railties/test/application/rake/framework_test.rb
@@ -16,14 +16,14 @@ module ApplicationTests
       end
 
       def load_tasks
-        require 'rake'
-        require 'rdoc/task'
-        require 'rake/testtask'
+        require "rake"
+        require "rdoc/task"
+        require "rake/testtask"
 
         Rails.application.load_tasks
       end
 
-      test 'requiring the rake task should not define method .app_generator on Object' do
+      test "requiring the rake task should not define method .app_generator on Object" do
         require "#{app_path}/config/environment"
 
         load_tasks
@@ -33,7 +33,7 @@ module ApplicationTests
         end
       end
 
-      test 'requiring the rake task should not define method .invoke_from_app_generator on Object' do
+      test "requiring the rake task should not define method .invoke_from_app_generator on Object" do
         require "#{app_path}/config/environment"
 
         load_tasks
diff --git a/railties/test/application/rake/migrations_test.rb b/railties/test/application/rake/migrations_test.rb
index 35f14a9b84..b3e95769fa 100644
--- a/railties/test/application/rake/migrations_test.rb
+++ b/railties/test/application/rake/migrations_test.rb
@@ -12,7 +12,7 @@ module ApplicationTests
         teardown_app
       end
 
-      test 'running migrations with given scope' do
+      test "running migrations with given scope" do
         Dir.chdir(app_path) do
           `bin/rails generate model user username:string password:string`
 
@@ -37,7 +37,7 @@ module ApplicationTests
         end
       end
 
-      test 'model and migration generator with change syntax' do
+      test "model and migration generator with change syntax" do
         Dir.chdir(app_path) do
           `bin/rails generate model user username:string password:string;
            bin/rails generate migration add_email_to_users email:string`
@@ -56,12 +56,12 @@ module ApplicationTests
         end
       end
 
-      test 'migration status when schema migrations table is not present' do
+      test "migration status when schema migrations table is not present" do
         output = Dir.chdir(app_path){ `bin/rails db:migrate:status 2>&1` }
         assert_equal "Schema migrations table does not exist yet.\n", output
       end
 
-      test 'test migration status' do
+      test "test migration status" do
         Dir.chdir(app_path) do
           `bin/rails generate model user username:string password:string;
            bin/rails generate migration add_email_to_users email:string;
@@ -80,8 +80,8 @@ module ApplicationTests
         end
       end
 
-      test 'migration status without timestamps' do
-        add_to_config('config.active_record.timestamped_migrations = false')
+      test "migration status without timestamps" do
+        add_to_config("config.active_record.timestamped_migrations = false")
 
         Dir.chdir(app_path) do
           `bin/rails generate model user username:string password:string;
@@ -101,7 +101,7 @@ module ApplicationTests
         end
       end
 
-      test 'test migration status after rollback and redo' do
+      test "test migration status after rollback and redo" do
         Dir.chdir(app_path) do
           `bin/rails generate model user username:string password:string;
            bin/rails generate migration add_email_to_users email:string;
@@ -126,8 +126,8 @@ module ApplicationTests
         end
       end
 
-      test 'migration status after rollback and redo without timestamps' do
-        add_to_config('config.active_record.timestamped_migrations = false')
+      test "migration status after rollback and redo without timestamps" do
+        add_to_config("config.active_record.timestamped_migrations = false")
 
         Dir.chdir(app_path) do
           `bin/rails generate model user username:string password:string;
@@ -153,7 +153,7 @@ module ApplicationTests
         end
       end
 
-      test 'running migrations with not timestamp head migration files' do
+      test "running migrations with not timestamp head migration files" do
         Dir.chdir(app_path) do
 
           app_file "db/migrate/1_one_migration.rb", <<-MIGRATION
@@ -175,8 +175,8 @@ module ApplicationTests
         end
       end
 
-      test 'schema generation when dump_schema_after_migration is set' do
-        add_to_config('config.active_record.dump_schema_after_migration = false')
+      test "schema generation when dump_schema_after_migration is set" do
+        add_to_config("config.active_record.dump_schema_after_migration = false")
 
         Dir.chdir(app_path) do
           `bin/rails generate model book title:string`
@@ -187,7 +187,7 @@ module ApplicationTests
           assert !File.exist?("db/schema.rb"), "should not dump schema when configured not to"
         end
 
-        add_to_config('config.active_record.dump_schema_after_migration = true')
+        add_to_config("config.active_record.dump_schema_after_migration = true")
 
         Dir.chdir(app_path) do
           `bin/rails generate model reviews book_id:integer`
@@ -198,7 +198,7 @@ module ApplicationTests
         end
       end
 
-      test 'default schema generation after migration' do
+      test "default schema generation after migration" do
         Dir.chdir(app_path) do
           `bin/rails generate model book title:string;
            bin/rails db:migrate`
@@ -208,7 +208,7 @@ module ApplicationTests
         end
       end
 
-      test 'test migration status migrated file is deleted' do
+      test "test migration status migrated file is deleted" do
         Dir.chdir(app_path) do
           `bin/rails generate model user username:string password:string;
            bin/rails generate migration add_email_to_users email:string;
@@ -216,7 +216,7 @@ module ApplicationTests
            rm db/migrate/*email*.rb`
 
           output = `bin/rails db:migrate:status`
-          File.write('test.txt', output)
+          File.write("test.txt", output)
 
           assert_match(/up\s+\d{14}\s+Create users/, output)
           assert_match(/up\s+\d{14}\s+\** NO FILE \**/, output)
diff --git a/railties/test/application/rake/notes_test.rb b/railties/test/application/rake/notes_test.rb
index 7d1e3efed2..c0ff3af193 100644
--- a/railties/test/application/rake/notes_test.rb
+++ b/railties/test/application/rake/notes_test.rb
@@ -1,5 +1,5 @@
 require "isolation/abstract_unit"
-require 'rails/source_annotation_extractor'
+require "rails/source_annotation_extractor"
 
 module ApplicationTests
   module RakeTests
@@ -17,15 +17,15 @@ module ApplicationTests
         teardown_app
       end
 
-      test 'notes finds notes for certain file_types' do
+      test "notes finds notes for certain file_types" do
         app_file "app/views/home/index.html.erb", "<% # TODO: note in erb %>"
         app_file "app/assets/javascripts/application.js", "// TODO: note in js"
         app_file "app/assets/stylesheets/application.css", "// TODO: note in css"
         app_file "app/controllers/application_controller.rb", 1000.times.map { "" }.join("\n") << "# TODO: note in ruby"
         app_file "lib/tasks/task.rake", "# TODO: note in rake"
-        app_file 'app/views/home/index.html.builder', '# TODO: note in builder'
-        app_file 'config/locales/en.yml', '# TODO: note in yml'
-        app_file 'config/locales/en.yaml', '# TODO: note in yaml'
+        app_file "app/views/home/index.html.builder", "# TODO: note in builder"
+        app_file "config/locales/en.yml", "# TODO: note in yml"
+        app_file "config/locales/en.yaml", "# TODO: note in yaml"
         app_file "app/views/home/index.ruby", "# TODO: note in ruby"
 
         run_rake_notes do |output, lines|
@@ -43,7 +43,7 @@ module ApplicationTests
         end
       end
 
-      test 'notes finds notes in default directories' do
+      test "notes finds notes in default directories" do
         app_file "app/controllers/some_controller.rb", "# TODO: note in app directory"
         app_file "config/initializers/some_initializer.rb", "# TODO: note in config directory"
         app_file "db/some_seeds.rb", "# TODO: note in db directory"
@@ -65,7 +65,7 @@ module ApplicationTests
         end
       end
 
-      test 'notes finds notes in custom directories' do
+      test "notes finds notes in custom directories" do
         app_file "app/controllers/some_controller.rb", "# TODO: note in app directory"
         app_file "config/initializers/some_initializer.rb", "# TODO: note in config directory"
         app_file "db/some_seeds.rb", "# TODO: note in db directory"
@@ -88,7 +88,7 @@ module ApplicationTests
         end
       end
 
-      test 'custom rake task finds specific notes in specific directories' do
+      test "custom rake task finds specific notes in specific directories" do
         app_file "app/controllers/some_controller.rb", "# TODO: note in app directory"
         app_file "lib/some_file.rb", "# OPTIMIZE: note in lib directory\n" << "# FIXME: note in lib directory"
         app_file "test/some_test.rb", 1000.times.map { "" }.join("\n") << "# TODO: note in test directory"
@@ -113,7 +113,7 @@ module ApplicationTests
         end
       end
 
-      test 'register a new extension' do
+      test "register a new extension" do
         add_to_config "config.assets.precompile = []"
         add_to_config %q{ config.annotations.register_extensions("scss", "sass") { |annotation| /\/\/\s*(#{annotation}):?\s*(.*)$/ } }
         app_file "app/assets/stylesheets/application.css.scss", "// TODO: note in scss"
@@ -126,7 +126,7 @@ module ApplicationTests
         end
       end
 
-      test 'register additional directories' do
+      test "register additional directories" do
         app_file "spec/spec_helper.rb", "# TODO: note in spec"
         app_file "spec/models/user_spec.rb", "# TODO: note in model spec"
         add_to_config %q{ config.annotations.register_directories("spec") }
@@ -140,7 +140,7 @@ module ApplicationTests
 
       private
 
-      def run_rake_notes(command = 'bin/rails notes')
+      def run_rake_notes(command = "bin/rails notes")
         boot_rails
         load_tasks
 
@@ -153,9 +153,9 @@ module ApplicationTests
       end
 
       def load_tasks
-        require 'rake'
-        require 'rdoc/task'
-        require 'rake/testtask'
+        require "rake"
+        require "rdoc/task"
+        require "rake/testtask"
 
         Rails.application.load_tasks
       end
diff --git a/railties/test/application/rake/restart_test.rb b/railties/test/application/rake/restart_test.rb
index 78769a6de5..28da8164a7 100644
--- a/railties/test/application/rake/restart_test.rb
+++ b/railties/test/application/rake/restart_test.rb
@@ -13,7 +13,7 @@ module ApplicationTests
         teardown_app
       end
 
-      test 'rake restart touches tmp/restart.txt' do
+      test "rake restart touches tmp/restart.txt" do
         Dir.chdir(app_path) do
           `rake restart`
           assert File.exist?("tmp/restart.txt")
@@ -26,15 +26,15 @@ module ApplicationTests
         end
       end
 
-      test 'rake restart should work even if tmp folder does not exist' do
+      test "rake restart should work even if tmp folder does not exist" do
         Dir.chdir(app_path) do
-          FileUtils.remove_dir('tmp')
+          FileUtils.remove_dir("tmp")
           `rake restart`
-          assert File.exist?('tmp/restart.txt')
+          assert File.exist?("tmp/restart.txt")
         end
       end
 
-      test 'rake restart removes server.pid also' do
+      test "rake restart removes server.pid also" do
         Dir.chdir(app_path) do
           FileUtils.mkdir_p("tmp/pids")
           FileUtils.touch("tmp/pids/server.pid")
diff --git a/railties/test/application/rake_test.rb b/railties/test/application/rake_test.rb
index 45ea506226..5bb97a593d 100644
--- a/railties/test/application/rake_test.rb
+++ b/railties/test/application/rake_test.rb
@@ -82,7 +82,7 @@ module ApplicationTests
         end
       RUBY
 
-      app_file 'app/models/hello.rb', <<-RUBY
+      app_file "app/models/hello.rb", <<-RUBY
         class Hello
           def world
             puts 'Hello world'
@@ -91,7 +91,7 @@ module ApplicationTests
       RUBY
 
       output = Dir.chdir(app_path) { `bin/rails do_nothing` }
-      assert_match 'Hello world', output
+      assert_match "Hello world", output
     end
 
     def test_should_not_eager_load_model_for_rake
@@ -102,17 +102,17 @@ module ApplicationTests
         end
       RUBY
 
-      add_to_env_config 'production', <<-RUBY
+      add_to_env_config "production", <<-RUBY
         config.eager_load = true
       RUBY
 
-      app_file 'app/models/hello.rb', <<-RUBY
+      app_file "app/models/hello.rb", <<-RUBY
         raise 'should not be pre-required for rake even eager_load=true'
       RUBY
 
       Dir.chdir(app_path) do
-        assert system('bin/rails do_nothing RAILS_ENV=production'),
-               'should not be pre-required for rake even eager_load=true'
+        assert system("bin/rails do_nothing RAILS_ENV=production"),
+               "should not be pre-required for rake even eager_load=true"
       end
     end
 
@@ -346,7 +346,7 @@ module ApplicationTests
         # ensure we have a schema_migrations table to dump
         `bin/rails db:migrate db:structure:dump SCHEMA=db/my_structure.sql`
       end
-      assert File.exist?(File.join(app_path, 'db', 'my_structure.sql'))
+      assert File.exist?(File.join(app_path, "db", "my_structure.sql"))
     end
 
     def test_rake_dump_structure_should_be_called_twice_when_migrate_redo
@@ -367,24 +367,24 @@ module ApplicationTests
          bin/rails generate model product name:string;
          bin/rails db:migrate db:schema:cache:dump`
       end
-      assert File.exist?(File.join(app_path, 'db', 'schema_cache.dump'))
+      assert File.exist?(File.join(app_path, "db", "schema_cache.dump"))
     end
 
     def test_rake_clear_schema_cache
       Dir.chdir(app_path) do
         `bin/rails db:schema:cache:dump db:schema:cache:clear`
       end
-      assert !File.exist?(File.join(app_path, 'db', 'schema_cache.dump'))
+      assert !File.exist?(File.join(app_path, "db", "schema_cache.dump"))
     end
 
     def test_copy_templates
       Dir.chdir(app_path) do
         `bin/rails app:templates:copy`
         %w(controller mailer scaffold).each do |dir|
-          assert File.exist?(File.join(app_path, 'lib', 'templates', 'erb', dir))
+          assert File.exist?(File.join(app_path, "lib", "templates", "erb", dir))
         end
         %w(controller helper scaffold_controller assets).each do |dir|
-          assert File.exist?(File.join(app_path, 'lib', 'templates', 'rails', dir))
+          assert File.exist?(File.join(app_path, "lib", "templates", "rails", dir))
         end
       end
     end
diff --git a/railties/test/application/rendering_test.rb b/railties/test/application/rendering_test.rb
index 9514547608..ccafc5b6f1 100644
--- a/railties/test/application/rendering_test.rb
+++ b/railties/test/application/rendering_test.rb
@@ -1,5 +1,5 @@
-require 'isolation/abstract_unit'
-require 'rack/test'
+require "isolation/abstract_unit"
+require "rack/test"
 
 module ApplicationTests
   class RoutingTest < ActiveSupport::TestCase
@@ -15,13 +15,13 @@ module ApplicationTests
     end
 
     test "Unknown format falls back to HTML template" do
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get 'pages/:id', to: 'pages#show'
         end
       RUBY
 
-      app_file 'app/controllers/pages_controller.rb', <<-RUBY
+      app_file "app/controllers/pages_controller.rb", <<-RUBY
         class PagesController < ApplicationController
           layout false
 
@@ -30,14 +30,14 @@ module ApplicationTests
         end
       RUBY
 
-      app_file 'app/views/pages/show.html.erb', <<-RUBY
+      app_file "app/views/pages/show.html.erb", <<-RUBY
         <%= params[:id] %>
       RUBY
 
-      get '/pages/foo'
+      get "/pages/foo"
       assert_equal 200, last_response.status
 
-      get '/pages/foo.bar'
+      get "/pages/foo.bar"
       assert_equal 200, last_response.status
     end
   end
diff --git a/railties/test/application/routing_test.rb b/railties/test/application/routing_test.rb
index 8e7df71880..27058cbc5c 100644
--- a/railties/test/application/routing_test.rb
+++ b/railties/test/application/routing_test.rb
@@ -1,5 +1,5 @@
-require 'isolation/abstract_unit'
-require 'rack/test'
+require "isolation/abstract_unit"
+require "rack/test"
 
 module ApplicationTests
   class RoutingTest < ActiveSupport::TestCase
@@ -60,7 +60,7 @@ module ApplicationTests
     test "root takes precedence over internal welcome controller" do
       app("development")
 
-      assert_welcome get('/')
+      assert_welcome get("/")
 
       controller :foo, <<-RUBY
         class FooController < ApplicationController
@@ -70,14 +70,14 @@ module ApplicationTests
         end
       RUBY
 
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           root to: "foo#index"
         end
       RUBY
 
-      get '/'
-      assert_equal 'foo', last_response.body
+      get "/"
+      assert_equal "foo", last_response.body
     end
 
     test "rails/welcome in production" do
@@ -107,8 +107,8 @@ module ApplicationTests
     test "simple controller" do
       simple_controller
 
-      get '/foo'
-      assert_equal 'foo', last_response.body
+      get "/foo"
+      assert_equal "foo", last_response.body
     end
 
     test "simple controller with helper" do
@@ -120,7 +120,7 @@ module ApplicationTests
         end
       RUBY
 
-      app_file 'app/helpers/bar_helper.rb', <<-RUBY
+      app_file "app/helpers/bar_helper.rb", <<-RUBY
         module BarHelper
           def foo_or_bar?
             "bar"
@@ -128,18 +128,18 @@ module ApplicationTests
         end
       RUBY
 
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get ':controller(/:action)'
         end
       RUBY
 
-      get '/foo'
-      assert_equal 'bar', last_response.body
+      get "/foo"
+      assert_equal "bar", last_response.body
     end
 
     test "mount rack app" do
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           mount lambda { |env| [200, {}, [env["PATH_INFO"]]] }, at: "/blog"
           # The line below is required because mount sometimes
@@ -148,8 +148,8 @@ module ApplicationTests
         end
       RUBY
 
-      get '/blog/archives'
-      assert_equal '/archives', last_response.body
+      get "/blog/archives"
+      assert_equal "/archives", last_response.body
     end
 
     test "mount named rack app" do
@@ -161,15 +161,15 @@ module ApplicationTests
         end
       RUBY
 
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           mount lambda { |env| [200, {}, [env["PATH_INFO"]]] }, at: "/blog", as: "my_blog"
           get '/foo' => 'foo#index'
         end
       RUBY
 
-      get '/foo'
-      assert_equal '/blog', last_response.body
+      get "/foo"
+      assert_equal "/blog", last_response.body
     end
 
     test "multiple controllers" do
@@ -189,21 +189,21 @@ module ApplicationTests
         end
       RUBY
 
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get ':controller(/:action)'
         end
       RUBY
 
-      get '/foo'
-      assert_equal 'foo', last_response.body
+      get "/foo"
+      assert_equal "foo", last_response.body
 
-      get '/bar'
-      assert_equal 'bar', last_response.body
+      get "/bar"
+      assert_equal "bar", last_response.body
     end
 
     test "nested controller" do
-      controller 'foo', <<-RUBY
+      controller "foo", <<-RUBY
         class FooController < ApplicationController
           def index
             render text: "foo"
@@ -211,7 +211,7 @@ module ApplicationTests
         end
       RUBY
 
-      controller 'admin/foo', <<-RUBY
+      controller "admin/foo", <<-RUBY
         module Admin
           class FooController < ApplicationController
             def index
@@ -221,22 +221,22 @@ module ApplicationTests
         end
       RUBY
 
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get 'admin/foo', to: 'admin/foo#index'
           get 'foo', to: 'foo#index'
         end
       RUBY
 
-      get '/foo'
-      assert_equal 'foo', last_response.body
+      get "/foo"
+      assert_equal "foo", last_response.body
 
-      get '/admin/foo'
-      assert_equal 'admin::foo', last_response.body
+      get "/admin/foo"
+      assert_equal "admin::foo", last_response.body
     end
 
     test "routes appending blocks" do
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get ':controller/:action'
         end
@@ -248,19 +248,19 @@ module ApplicationTests
         end
       R
 
-      app 'development'
+      app "development"
 
-      get '/win'
-      assert_equal 'WIN', last_response.body
+      get "/win"
+      assert_equal "WIN", last_response.body
 
-      app_file 'config/routes.rb', <<-R
+      app_file "config/routes.rb", <<-R
         Rails.application.routes.draw do
           get 'lol' => 'hello#index'
         end
       R
 
-      get '/win'
-      assert_equal 'WIN', last_response.body
+      get "/win"
+      assert_equal "WIN", last_response.body
     end
 
     {"development" => "baz", "production" => "bar"}.each do |mode, expected|
@@ -277,7 +277,7 @@ module ApplicationTests
           end
         RUBY
 
-        app_file 'config/routes.rb', <<-RUBY
+        app_file "config/routes.rb", <<-RUBY
           Rails.application.routes.draw do
             get 'foo', to: 'foo#bar'
           end
@@ -285,10 +285,10 @@ module ApplicationTests
 
         app(mode)
 
-        get '/foo'
-        assert_equal 'bar', last_response.body
+        get "/foo"
+        assert_equal "bar", last_response.body
 
-        app_file 'config/routes.rb', <<-RUBY
+        app_file "config/routes.rb", <<-RUBY
           Rails.application.routes.draw do
             get 'foo', to: 'foo#baz'
           end
@@ -296,12 +296,12 @@ module ApplicationTests
 
         sleep 0.1
 
-        get '/foo'
+        get "/foo"
         assert_equal expected, last_response.body
       end
     end
 
-    test 'routes are loaded just after initialization' do
+    test "routes are loaded just after initialization" do
       require "#{app_path}/config/application"
 
       # Create the rack app just inside after initialize callback
@@ -309,17 +309,17 @@ module ApplicationTests
         ::InitializeRackApp = lambda { |env| [200, {}, ["InitializeRackApp"]] }
       end
 
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get 'foo', to: ::InitializeRackApp
         end
       RUBY
 
-      get '/foo'
+      get "/foo"
       assert_equal "InitializeRackApp", last_response.body
     end
 
-    test 'reload_routes! is part of Rails.application API' do
+    test "reload_routes! is part of Rails.application API" do
       app("development")
       assert_nothing_raised do
         Rails.application.reload_routes!
@@ -327,7 +327,7 @@ module ApplicationTests
     end
 
     def test_root_path
-      app('development')
+      app("development")
 
       controller :foo, <<-RUBY
         class FooController < ApplicationController
@@ -337,21 +337,21 @@ module ApplicationTests
         end
       RUBY
 
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get 'foo', :to => 'foo#index'
           root :to => 'foo#index'
         end
       RUBY
 
-      remove_file 'public/index.html'
+      remove_file "public/index.html"
 
-      get '/'
-      assert_equal 'foo', last_response.body
+      get "/"
+      assert_equal "foo", last_response.body
     end
 
-    test 'routes are added and removed when reloading' do
-      app('development')
+    test "routes are added and removed when reloading" do
+      app("development")
 
       controller :foo, <<-RUBY
         class FooController < ApplicationController
@@ -369,23 +369,23 @@ module ApplicationTests
         end
       RUBY
 
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get 'foo', to: 'foo#index'
         end
       RUBY
 
-      get '/foo'
-      assert_equal 'foo', last_response.body
-      assert_equal '/foo', Rails.application.routes.url_helpers.foo_path
+      get "/foo"
+      assert_equal "foo", last_response.body
+      assert_equal "/foo", Rails.application.routes.url_helpers.foo_path
 
-      get '/bar'
+      get "/bar"
       assert_equal 404, last_response.status
       assert_raises NoMethodError do
-        assert_equal '/bar', Rails.application.routes.url_helpers.bar_path
+        assert_equal "/bar", Rails.application.routes.url_helpers.bar_path
       end
 
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get 'foo', to: 'foo#index'
           get 'bar', to: 'bar#index'
@@ -394,15 +394,15 @@ module ApplicationTests
 
       Rails.application.reload_routes!
 
-      get '/foo'
-      assert_equal 'foo', last_response.body
-      assert_equal '/foo', Rails.application.routes.url_helpers.foo_path
+      get "/foo"
+      assert_equal "foo", last_response.body
+      assert_equal "/foo", Rails.application.routes.url_helpers.foo_path
 
-      get '/bar'
-      assert_equal 'bar', last_response.body
-      assert_equal '/bar', Rails.application.routes.url_helpers.bar_path
+      get "/bar"
+      assert_equal "bar", last_response.body
+      assert_equal "/bar", Rails.application.routes.url_helpers.bar_path
 
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get 'foo', to: 'foo#index'
         end
@@ -410,19 +410,19 @@ module ApplicationTests
 
       Rails.application.reload_routes!
 
-      get '/foo'
-      assert_equal 'foo', last_response.body
-      assert_equal '/foo', Rails.application.routes.url_helpers.foo_path
+      get "/foo"
+      assert_equal "foo", last_response.body
+      assert_equal "/foo", Rails.application.routes.url_helpers.foo_path
 
-      get '/bar'
+      get "/bar"
       assert_equal 404, last_response.status
       assert_raises NoMethodError do
-        assert_equal '/bar', Rails.application.routes.url_helpers.bar_path
+        assert_equal "/bar", Rails.application.routes.url_helpers.bar_path
       end
     end
 
-    test 'named routes are cleared when reloading' do
-      app('development')
+    test "named routes are cleared when reloading" do
+      app("development")
 
       controller :foo, <<-RUBY
         class FooController < ApplicationController
@@ -440,17 +440,17 @@ module ApplicationTests
         end
       RUBY
 
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get ':locale/foo', to: 'foo#index', as: 'foo'
         end
       RUBY
 
-      get '/en/foo'
-      assert_equal 'foo', last_response.body
-      assert_equal '/en/foo', Rails.application.routes.url_helpers.foo_path(:locale => 'en')
+      get "/en/foo"
+      assert_equal "foo", last_response.body
+      assert_equal "/en/foo", Rails.application.routes.url_helpers.foo_path(:locale => "en")
 
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get ':locale/bar', to: 'bar#index', as: 'foo'
         end
@@ -458,28 +458,28 @@ module ApplicationTests
 
       Rails.application.reload_routes!
 
-      get '/en/foo'
+      get "/en/foo"
       assert_equal 404, last_response.status
 
-      get '/en/bar'
-      assert_equal 'bar', last_response.body
-      assert_equal '/en/bar', Rails.application.routes.url_helpers.foo_path(:locale => 'en')
+      get "/en/bar"
+      assert_equal "bar", last_response.body
+      assert_equal "/en/bar", Rails.application.routes.url_helpers.foo_path(:locale => "en")
     end
 
-    test 'resource routing with irregular inflection' do
-      app_file 'config/initializers/inflection.rb', <<-RUBY
+    test "resource routing with irregular inflection" do
+      app_file "config/initializers/inflection.rb", <<-RUBY
         ActiveSupport::Inflector.inflections do |inflect|
           inflect.irregular 'yazi', 'yazilar'
         end
       RUBY
 
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           resources :yazilar
         end
       RUBY
 
-      controller 'yazilar', <<-RUBY
+      controller "yazilar", <<-RUBY
         class YazilarController < ApplicationController
           def index
             render text: 'yazilar#index'
@@ -487,10 +487,10 @@ module ApplicationTests
         end
       RUBY
 
-      get '/yazilars'
+      get "/yazilars"
       assert_equal 404, last_response.status
 
-      get '/yazilar'
+      get "/yazilar"
       assert_equal 200, last_response.status
     end
   end
diff --git a/railties/test/application/runner_test.rb b/railties/test/application/runner_test.rb
index 84d90cc6d7..1c4aa1d4c4 100644
--- a/railties/test/application/runner_test.rb
+++ b/railties/test/application/runner_test.rb
@@ -1,5 +1,5 @@
-require 'isolation/abstract_unit'
-require 'env_helpers'
+require "isolation/abstract_unit"
+require "env_helpers"
 
 module ApplicationTests
   class RunnerTest < ActiveSupport::TestCase
diff --git a/railties/test/application/test_runner_test.rb b/railties/test/application/test_runner_test.rb
index 08759ab5a4..b442891769 100644
--- a/railties/test/application/test_runner_test.rb
+++ b/railties/test/application/test_runner_test.rb
@@ -1,6 +1,6 @@
-require 'isolation/abstract_unit'
-require 'active_support/core_ext/string/strip'
-require 'env_helpers'
+require "isolation/abstract_unit"
+require "active_support/core_ext/string/strip"
+require "env_helpers"
 
 module ApplicationTests
   class TestRunnerTest < ActiveSupport::TestCase
@@ -16,31 +16,31 @@ module ApplicationTests
     end
 
     def test_run_single_file
-      create_test_file :models, 'foo'
-      create_test_file :models, 'bar'
+      create_test_file :models, "foo"
+      create_test_file :models, "bar"
       assert_match "1 runs, 1 assertions, 0 failures", run_test_command("test/models/foo_test.rb")
     end
 
     def test_run_multiple_files
-      create_test_file :models,  'foo'
-      create_test_file :models,  'bar'
+      create_test_file :models,  "foo"
+      create_test_file :models,  "bar"
       assert_match "2 runs, 2 assertions, 0 failures", run_test_command("test/models/foo_test.rb test/models/bar_test.rb")
     end
 
     def test_run_file_with_syntax_error
-      app_file 'test/models/error_test.rb', <<-RUBY
+      app_file "test/models/error_test.rb", <<-RUBY
         require 'test_helper'
         def; end
       RUBY
 
-      error = capture(:stderr) { run_test_command('test/models/error_test.rb') }
+      error = capture(:stderr) { run_test_command("test/models/error_test.rb") }
       assert_match "syntax error", error
     end
 
     def test_run_models
-      create_test_file :models, 'foo'
-      create_test_file :models, 'bar'
-      create_test_file :controllers, 'foobar_controller'
+      create_test_file :models, "foo"
+      create_test_file :models, "bar"
+      create_test_file :controllers, "foobar_controller"
       run_test_command("test/models").tap do |output|
         assert_match "FooTest", output
         assert_match "BarTest", output
@@ -49,9 +49,9 @@ module ApplicationTests
     end
 
     def test_run_helpers
-      create_test_file :helpers, 'foo_helper'
-      create_test_file :helpers, 'bar_helper'
-      create_test_file :controllers, 'foobar_controller'
+      create_test_file :helpers, "foo_helper"
+      create_test_file :helpers, "bar_helper"
+      create_test_file :controllers, "foobar_controller"
       run_test_command("test/helpers").tap do |output|
         assert_match "FooHelperTest", output
         assert_match "BarHelperTest", output
@@ -61,10 +61,10 @@ module ApplicationTests
 
     def test_run_units
       skip "we no longer have the concept of unit tests. Just different directories..."
-      create_test_file :models, 'foo'
-      create_test_file :helpers, 'bar_helper'
-      create_test_file :unit, 'baz_unit'
-      create_test_file :controllers, 'foobar_controller'
+      create_test_file :models, "foo"
+      create_test_file :helpers, "bar_helper"
+      create_test_file :unit, "baz_unit"
+      create_test_file :controllers, "foobar_controller"
       run_test_units_command.tap do |output|
         assert_match "FooTest", output
         assert_match "BarHelperTest", output
@@ -74,9 +74,9 @@ module ApplicationTests
     end
 
     def test_run_controllers
-      create_test_file :controllers, 'foo_controller'
-      create_test_file :controllers, 'bar_controller'
-      create_test_file :models, 'foo'
+      create_test_file :controllers, "foo_controller"
+      create_test_file :controllers, "bar_controller"
+      create_test_file :models, "foo"
       run_test_command("test/controllers").tap do |output|
         assert_match "FooControllerTest", output
         assert_match "BarControllerTest", output
@@ -85,9 +85,9 @@ module ApplicationTests
     end
 
     def test_run_mailers
-      create_test_file :mailers, 'foo_mailer'
-      create_test_file :mailers, 'bar_mailer'
-      create_test_file :models, 'foo'
+      create_test_file :mailers, "foo_mailer"
+      create_test_file :mailers, "bar_mailer"
+      create_test_file :models, "foo"
       run_test_command("test/mailers").tap do |output|
         assert_match "FooMailerTest", output
         assert_match "BarMailerTest", output
@@ -96,9 +96,9 @@ module ApplicationTests
     end
 
     def test_run_jobs
-      create_test_file :jobs, 'foo_job'
-      create_test_file :jobs, 'bar_job'
-      create_test_file :models, 'foo'
+      create_test_file :jobs, "foo_job"
+      create_test_file :jobs, "bar_job"
+      create_test_file :models, "foo"
       run_test_command("test/jobs").tap do |output|
         assert_match "FooJobTest", output
         assert_match "BarJobTest", output
@@ -108,10 +108,10 @@ module ApplicationTests
 
     def test_run_functionals
       skip "we no longer have the concept of functional tests. Just different directories..."
-      create_test_file :mailers, 'foo_mailer'
-      create_test_file :controllers, 'bar_controller'
-      create_test_file :functional, 'baz_functional'
-      create_test_file :models, 'foo'
+      create_test_file :mailers, "foo_mailer"
+      create_test_file :controllers, "bar_controller"
+      create_test_file :functional, "baz_functional"
+      create_test_file :models, "foo"
       run_test_functionals_command.tap do |output|
         assert_match "FooMailerTest", output
         assert_match "BarControllerTest", output
@@ -121,8 +121,8 @@ module ApplicationTests
     end
 
     def test_run_integration
-      create_test_file :integration, 'foo_integration'
-      create_test_file :models, 'foo'
+      create_test_file :integration, "foo_integration"
+      create_test_file :models, "foo"
       run_test_command("test/integration").tap do |output|
         assert_match "FooIntegration", output
         assert_match "1 runs, 1 assertions, 0 failures", output
@@ -132,14 +132,14 @@ module ApplicationTests
     def test_run_all_suites
       suites = [:models, :helpers, :unit, :controllers, :mailers, :functional, :integration, :jobs]
       suites.each { |suite| create_test_file suite, "foo_#{suite}" }
-      run_test_command('') .tap do |output|
+      run_test_command("") .tap do |output|
         suites.each { |suite| assert_match "Foo#{suite.to_s.camelize}Test", output }
         assert_match "8 runs, 8 assertions, 0 failures", output
       end
     end
 
     def test_run_named_test
-      app_file 'test/unit/chu_2_koi_test.rb', <<-RUBY
+      app_file "test/unit/chu_2_koi_test.rb", <<-RUBY
         require 'test_helper'
 
         class Chu2KoiTest < ActiveSupport::TestCase
@@ -153,14 +153,14 @@ module ApplicationTests
         end
       RUBY
 
-      run_test_command('-n test_rikka test/unit/chu_2_koi_test.rb').tap do |output|
+      run_test_command("-n test_rikka test/unit/chu_2_koi_test.rb").tap do |output|
         assert_match "Rikka", output
         assert_no_match "Sanae", output
       end
     end
 
     def test_run_matched_test
-      app_file 'test/unit/chu_2_koi_test.rb', <<-RUBY
+      app_file "test/unit/chu_2_koi_test.rb", <<-RUBY
         require 'test_helper'
 
         class Chu2KoiTest < ActiveSupport::TestCase
@@ -174,7 +174,7 @@ module ApplicationTests
         end
       RUBY
 
-      run_test_command('-n /rikka/ test/unit/chu_2_koi_test.rb').tap do |output|
+      run_test_command("-n /rikka/ test/unit/chu_2_koi_test.rb").tap do |output|
         assert_match "Rikka", output
         assert_no_match "Sanae", output
       end
@@ -195,14 +195,14 @@ module ApplicationTests
     def test_run_with_model
       skip "These feel a bit odd. Not sure we should keep supporting them."
       create_model_with_fixture
-      create_fixture_test 'models', 'user'
+      create_fixture_test "models", "user"
       assert_match "3 users", run_task(["test models/user"])
       assert_match "3 users", run_task(["test app/models/user.rb"])
     end
 
     def test_run_different_environment_using_env_var
       skip "no longer possible. Running tests in a different environment should be explicit"
-      app_file 'test/unit/env_test.rb', <<-RUBY
+      app_file "test/unit/env_test.rb", <<-RUBY
         require 'test_helper'
 
         class EnvTest < ActiveSupport::TestCase
@@ -212,14 +212,14 @@ module ApplicationTests
         end
       RUBY
 
-      ENV['RAILS_ENV'] = 'development'
-      assert_match "development", run_test_command('test/unit/env_test.rb')
+      ENV["RAILS_ENV"] = "development"
+      assert_match "development", run_test_command("test/unit/env_test.rb")
     end
 
     def test_run_in_test_environment_by_default
       create_env_test
 
-      assert_match "Current Environment: test", run_test_command('test/unit/env_test.rb')
+      assert_match "Current Environment: test", run_test_command("test/unit/env_test.rb")
     end
 
     def test_run_different_environment
@@ -231,27 +231,27 @@ module ApplicationTests
 
     def test_generated_scaffold_works_with_rails_test
       create_scaffold
-      assert_match "0 failures, 0 errors, 0 skips", run_test_command('')
+      assert_match "0 failures, 0 errors, 0 skips", run_test_command("")
     end
 
     def test_generated_controller_works_with_rails_test
       create_controller
-      assert_match "0 failures, 0 errors, 0 skips", run_test_command('')
+      assert_match "0 failures, 0 errors, 0 skips", run_test_command("")
     end
 
     def test_run_multiple_folders
-      create_test_file :models, 'account'
-      create_test_file :controllers, 'accounts_controller'
+      create_test_file :models, "account"
+      create_test_file :controllers, "accounts_controller"
 
-      run_test_command('test/models test/controllers').tap do |output|
-        assert_match 'AccountTest', output
-        assert_match 'AccountsControllerTest', output
-        assert_match '2 runs, 2 assertions, 0 failures, 0 errors, 0 skips', output
+      run_test_command("test/models test/controllers").tap do |output|
+        assert_match "AccountTest", output
+        assert_match "AccountsControllerTest", output
+        assert_match "2 runs, 2 assertions, 0 failures, 0 errors, 0 skips", output
       end
     end
 
     def test_run_with_ruby_command
-      app_file 'test/models/post_test.rb', <<-RUBY
+      app_file "test/models/post_test.rb", <<-RUBY
         require 'test_helper'
 
         class PostTest < ActiveSupport::TestCase
@@ -264,15 +264,15 @@ module ApplicationTests
 
       Dir.chdir(app_path) do
         `ruby -Itest test/models/post_test.rb`.tap do |output|
-          assert_match 'PostTest', output
-          assert_no_match 'is already defined in', output
+          assert_match "PostTest", output
+          assert_no_match "is already defined in", output
         end
       end
     end
 
     def test_mix_files_and_line_filters
-      create_test_file :models, 'account'
-      app_file 'test/models/post_test.rb', <<-RUBY
+      create_test_file :models, "account"
+      app_file "test/models/post_test.rb", <<-RUBY
         require 'test_helper'
 
         class PostTest < ActiveSupport::TestCase
@@ -287,15 +287,15 @@ module ApplicationTests
         end
       RUBY
 
-      run_test_command('test/models/account_test.rb test/models/post_test.rb:4').tap do |output|
-        assert_match 'AccountTest', output
-        assert_match 'PostTest', output
-        assert_match '2 runs, 2 assertions', output
+      run_test_command("test/models/account_test.rb test/models/post_test.rb:4").tap do |output|
+        assert_match "AccountTest", output
+        assert_match "PostTest", output
+        assert_match "2 runs, 2 assertions", output
       end
     end
 
     def test_more_than_one_line_filter
-      app_file 'test/models/post_test.rb', <<-RUBY
+      app_file "test/models/post_test.rb", <<-RUBY
         require 'test_helper'
 
         class PostTest < ActiveSupport::TestCase
@@ -315,15 +315,15 @@ module ApplicationTests
         end
       RUBY
 
-      run_test_command('test/models/post_test.rb:4:9').tap do |output|
-        assert_match 'PostTest:FirstFilter', output
-        assert_match 'PostTest:SecondFilter', output
-        assert_match '2 runs, 2 assertions', output
+      run_test_command("test/models/post_test.rb:4:9").tap do |output|
+        assert_match "PostTest:FirstFilter", output
+        assert_match "PostTest:SecondFilter", output
+        assert_match "2 runs, 2 assertions", output
       end
     end
 
     def test_more_than_one_line_filter_with_multiple_files
-      app_file 'test/models/account_test.rb', <<-RUBY
+      app_file "test/models/account_test.rb", <<-RUBY
         require 'test_helper'
 
         class AccountTest < ActiveSupport::TestCase
@@ -343,7 +343,7 @@ module ApplicationTests
         end
       RUBY
 
-      app_file 'test/models/post_test.rb', <<-RUBY
+      app_file "test/models/post_test.rb", <<-RUBY
         require 'test_helper'
 
         class PostTest < ActiveSupport::TestCase
@@ -363,27 +363,27 @@ module ApplicationTests
         end
       RUBY
 
-      run_test_command('test/models/account_test.rb:4:9 test/models/post_test.rb:4:9').tap do |output|
-        assert_match 'AccountTest:FirstFilter', output
-        assert_match 'AccountTest:SecondFilter', output
-        assert_match 'PostTest:FirstFilter', output
-        assert_match 'PostTest:SecondFilter', output
-        assert_match '4 runs, 4 assertions', output
+      run_test_command("test/models/account_test.rb:4:9 test/models/post_test.rb:4:9").tap do |output|
+        assert_match "AccountTest:FirstFilter", output
+        assert_match "AccountTest:SecondFilter", output
+        assert_match "PostTest:FirstFilter", output
+        assert_match "PostTest:SecondFilter", output
+        assert_match "4 runs, 4 assertions", output
       end
     end
 
     def test_multiple_line_filters
-      create_test_file :models, 'account'
-      create_test_file :models, 'post'
+      create_test_file :models, "account"
+      create_test_file :models, "post"
 
-      run_test_command('test/models/account_test.rb:4 test/models/post_test.rb:4').tap do |output|
-        assert_match 'AccountTest', output
-        assert_match 'PostTest', output
+      run_test_command("test/models/account_test.rb:4 test/models/post_test.rb:4").tap do |output|
+        assert_match "AccountTest", output
+        assert_match "PostTest", output
       end
     end
 
     def test_line_filters_trigger_only_one_runnable
-      app_file 'test/models/post_test.rb', <<-RUBY
+      app_file "test/models/post_test.rb", <<-RUBY
         require 'test_helper'
 
         class PostTest < ActiveSupport::TestCase
@@ -400,14 +400,14 @@ module ApplicationTests
       RUBY
 
       # Pass seed guaranteeing failure.
-      run_test_command('test/models/post_test.rb:4 --seed 30410').tap do |output|
-        assert_no_match 'ran second runnable', output
-        assert_match '1 runs, 1 assertions', output
+      run_test_command("test/models/post_test.rb:4 --seed 30410").tap do |output|
+        assert_no_match "ran second runnable", output
+        assert_match "1 runs, 1 assertions", output
       end
     end
 
     def test_line_filter_with_minitest_string_filter
-      app_file 'test/models/post_test.rb', <<-RUBY
+      app_file "test/models/post_test.rb", <<-RUBY
         require 'test_helper'
 
         class PostTest < ActiveSupport::TestCase
@@ -423,128 +423,128 @@ module ApplicationTests
         end
       RUBY
 
-      run_test_command('test/models/post_test.rb:4 -n test_by_name').tap do |output|
-        assert_match 'by line', output
-        assert_match 'by name', output
-        assert_match '2 runs, 2 assertions', output
+      run_test_command("test/models/post_test.rb:4 -n test_by_name").tap do |output|
+        assert_match "by line", output
+        assert_match "by name", output
+        assert_match "2 runs, 2 assertions", output
       end
     end
 
     def test_shows_filtered_backtrace_by_default
       create_backtrace_test
 
-      assert_match 'Rails::BacktraceCleaner', run_test_command('test/unit/backtrace_test.rb')
+      assert_match "Rails::BacktraceCleaner", run_test_command("test/unit/backtrace_test.rb")
     end
 
     def test_backtrace_option
       create_backtrace_test
 
-      assert_match 'Minitest::BacktraceFilter', run_test_command('test/unit/backtrace_test.rb -b')
-      assert_match 'Minitest::BacktraceFilter',
-        run_test_command('test/unit/backtrace_test.rb --backtrace')
+      assert_match "Minitest::BacktraceFilter", run_test_command("test/unit/backtrace_test.rb -b")
+      assert_match "Minitest::BacktraceFilter",
+        run_test_command("test/unit/backtrace_test.rb --backtrace")
     end
 
     def test_show_full_backtrace_using_backtrace_environment_variable
       create_backtrace_test
 
-      switch_env 'BACKTRACE', 'true' do
-        assert_match 'Minitest::BacktraceFilter', run_test_command('test/unit/backtrace_test.rb')
+      switch_env "BACKTRACE", "true" do
+        assert_match "Minitest::BacktraceFilter", run_test_command("test/unit/backtrace_test.rb")
       end
     end
 
     def test_run_app_without_rails_loaded
       # Simulate a real Rails app boot.
-      app_file 'config/boot.rb', <<-RUBY
+      app_file "config/boot.rb", <<-RUBY
         ENV['BUNDLE_GEMFILE'] ||= File.expand_path('../../Gemfile', __FILE__)
 
         require 'bundler/setup' # Set up gems listed in the Gemfile.
       RUBY
 
-      assert_match '0 runs, 0 assertions', run_test_command('')
+      assert_match "0 runs, 0 assertions", run_test_command("")
     end
 
     def test_output_inline_by_default
-      create_test_file :models, 'post', pass: false
+      create_test_file :models, "post", pass: false
 
-      output = run_test_command('test/models/post_test.rb')
+      output = run_test_command("test/models/post_test.rb")
       expect = %r{Running:\n\nPostTest\nF\n\nFailure:\nPostTest#test_truth \[[^\]]+test/models/post_test.rb:6\]:\nwups!\n\nbin/rails test test/models/post_test.rb:4\n\n\n\n}
       assert_match expect, output
     end
 
     def test_only_inline_failure_output
-      create_test_file :models, 'post', pass: false
+      create_test_file :models, "post", pass: false
 
-      output = run_test_command('test/models/post_test.rb')
+      output = run_test_command("test/models/post_test.rb")
       assert_match %r{Finished in.*\n\n1 runs, 1 assertions}, output
     end
 
     def test_fail_fast
-      create_test_file :models, 'post', pass: false
+      create_test_file :models, "post", pass: false
 
       assert_match(/Interrupt/,
-        capture(:stderr) { run_test_command('test/models/post_test.rb --fail-fast') })
+        capture(:stderr) { run_test_command("test/models/post_test.rb --fail-fast") })
     end
 
     def test_raise_error_when_specified_file_does_not_exist
-      error = capture(:stderr) { run_test_command('test/not_exists.rb') }
+      error = capture(:stderr) { run_test_command("test/not_exists.rb") }
       assert_match(%r{cannot load such file.+test/not_exists\.rb}, error)
     end
 
     def test_pass_TEST_env_on_rake_test
-      create_test_file :models, 'account'
-      create_test_file :models, 'post', pass: false
+      create_test_file :models, "account"
+      create_test_file :models, "post", pass: false
       # This specifically verifies TEST for backwards compatibility with rake test
       # as bin/rails test already supports running tests from a single file more cleanly.
       output =  Dir.chdir(app_path) { `bin/rake test TEST=test/models/post_test.rb` }
 
       assert_match "PostTest", output, "passing TEST= should run selected test"
       assert_no_match "AccountTest", output, "passing TEST= should only run selected test"
-      assert_match '1 runs, 1 assertions', output
+      assert_match "1 runs, 1 assertions", output
     end
 
     def test_pass_rake_options
-      create_test_file :models, 'account'
+      create_test_file :models, "account"
       output =  Dir.chdir(app_path) { `bin/rake --rakefile Rakefile --trace=stdout test` }
 
-      assert_match '1 runs, 1 assertions', output
-      assert_match 'Execute test', output
+      assert_match "1 runs, 1 assertions", output
+      assert_match "Execute test", output
     end
 
     def test_rails_db_create_all_restores_db_connection
-      create_test_file :models, 'account'
+      create_test_file :models, "account"
       output =  Dir.chdir(app_path) { `bin/rails db:create:all db:migrate && echo ".tables" | rails dbconsole` }
       assert_match "ar_internal_metadata", output, "tables should be dumped"
     end
 
     def test_rails_db_create_all_restores_db_connection_after_drop
-      create_test_file :models, 'account'
+      create_test_file :models, "account"
       Dir.chdir(app_path) { `bin/rails db:create:all` } # create all to avoid warnings
       output =  Dir.chdir(app_path) { `bin/rails db:drop:all db:create:all db:migrate && echo ".tables" | rails dbconsole` }
       assert_match "ar_internal_metadata", output, "tables should be dumped"
     end
 
     def test_rake_passes_TESTOPTS_to_minitest
-      create_test_file :models, 'account'
+      create_test_file :models, "account"
       output =  Dir.chdir(app_path) { `bin/rake test TESTOPTS=-v` }
       assert_match "AccountTest#test_truth", output, "passing TEST= should run selected test"
     end
 
     def test_rake_passes_multiple_TESTOPTS_to_minitest
-      create_test_file :models, 'account'
+      create_test_file :models, "account"
       output =  Dir.chdir(app_path) { `bin/rake test TESTOPTS='-v --seed=1234'` }
       assert_match "AccountTest#test_truth", output, "passing TEST= should run selected test"
       assert_match "seed=1234", output, "passing TEST= should run selected test"
     end
 
     private
-      def run_test_command(arguments = 'test/unit/test_test.rb')
+      def run_test_command(arguments = "test/unit/test_test.rb")
         Dir.chdir(app_path) { `bin/rails t #{arguments}` }
       end
 
       def create_model_with_fixture
-        script 'generate model user name:string'
+        script "generate model user name:string"
 
-        app_file 'test/fixtures/users.yml', <<-YAML.strip_heredoc
+        app_file "test/fixtures/users.yml", <<-YAML.strip_heredoc
           vampire:
             id: 1
             name: Koyomi Araragi
@@ -559,7 +559,7 @@ module ApplicationTests
         run_migration
       end
 
-      def create_fixture_test(path = :unit, name = 'test')
+      def create_fixture_test(path = :unit, name = "test")
         app_file "test/#{path}/#{name}_test.rb", <<-RUBY
           require 'test_helper'
 
@@ -572,7 +572,7 @@ module ApplicationTests
       end
 
       def create_backtrace_test
-        app_file 'test/unit/backtrace_test.rb', <<-RUBY
+        app_file "test/unit/backtrace_test.rb", <<-RUBY
           require 'test_helper'
 
           class BacktraceTest < ActiveSupport::TestCase
@@ -584,10 +584,10 @@ module ApplicationTests
       end
 
       def create_schema
-        app_file 'db/schema.rb', ''
+        app_file "db/schema.rb", ""
       end
 
-      def create_test_file(path = :unit, name = 'test', pass: true)
+      def create_test_file(path = :unit, name = "test", pass: true)
         app_file "test/#{path}/#{name}_test.rb", <<-RUBY
           require 'test_helper'
 
@@ -601,7 +601,7 @@ module ApplicationTests
       end
 
       def create_env_test
-        app_file 'test/unit/env_test.rb', <<-RUBY
+        app_file "test/unit/env_test.rb", <<-RUBY
           require 'test_helper'
 
           class EnvTest < ActiveSupport::TestCase
@@ -613,13 +613,13 @@ module ApplicationTests
       end
 
       def create_scaffold
-        script 'generate scaffold user name:string'
-        Dir.chdir(app_path) { File.exist?('app/models/user.rb') }
+        script "generate scaffold user name:string"
+        Dir.chdir(app_path) { File.exist?("app/models/user.rb") }
         run_migration
       end
 
       def create_controller
-        script 'generate controller admin/dashboard index'
+        script "generate controller admin/dashboard index"
       end
 
       def run_migration
diff --git a/railties/test/application/test_test.rb b/railties/test/application/test_test.rb
index 1e9d35287e..ef65c7a893 100644
--- a/railties/test/application/test_test.rb
+++ b/railties/test/application/test_test.rb
@@ -1,4 +1,4 @@
-require 'isolation/abstract_unit'
+require "isolation/abstract_unit"
 
 module ApplicationTests
   class TestTest < ActiveSupport::TestCase
@@ -13,7 +13,7 @@ module ApplicationTests
     end
 
     test "truth" do
-      app_file 'test/unit/foo_test.rb', <<-RUBY
+      app_file "test/unit/foo_test.rb", <<-RUBY
         require 'test_helper'
 
         class FooTest < ActiveSupport::TestCase
@@ -23,20 +23,20 @@ module ApplicationTests
         end
       RUBY
 
-      assert_successful_test_run 'unit/foo_test.rb'
+      assert_successful_test_run "unit/foo_test.rb"
     end
 
     test "integration test" do
-      controller 'posts', <<-RUBY
+      controller "posts", <<-RUBY
         class PostsController < ActionController::Base
         end
       RUBY
 
-      app_file 'app/views/posts/index.html.erb', <<-HTML
+      app_file "app/views/posts/index.html.erb", <<-HTML
         Posts#index
       HTML
 
-      app_file 'test/integration/posts_test.rb', <<-RUBY
+      app_file "test/integration/posts_test.rb", <<-RUBY
         require 'test_helper'
 
         class PostsTest < ActionDispatch::IntegrationTest
@@ -48,11 +48,11 @@ module ApplicationTests
         end
       RUBY
 
-      assert_successful_test_run 'integration/posts_test.rb'
+      assert_successful_test_run "integration/posts_test.rb"
     end
 
     test "enable full backtraces on test failures" do
-      app_file 'test/unit/failing_test.rb', <<-RUBY
+      app_file "test/unit/failing_test.rb", <<-RUBY
         require 'test_helper'
 
         class FailingTest < ActiveSupport::TestCase
@@ -62,16 +62,16 @@ module ApplicationTests
         end
       RUBY
 
-      output = run_test_file('unit/failing_test.rb', env: { "BACKTRACE" => "1" })
+      output = run_test_file("unit/failing_test.rb", env: { "BACKTRACE" => "1" })
       assert_match %r{test/unit/failing_test\.rb}, output
       assert_match %r{test/unit/failing_test\.rb:4}, output
     end
 
     test "ruby schema migrations" do
-      output  = script('generate model user name:string')
+      output  = script("generate model user name:string")
       version = output.match(/(\d+)_create_users\.rb/)[1]
 
-      app_file 'test/models/user_test.rb', <<-RUBY
+      app_file "test/models/user_test.rb", <<-RUBY
         require 'test_helper'
 
         class UserTest < ActiveSupport::TestCase
@@ -80,11 +80,11 @@ module ApplicationTests
           end
         end
       RUBY
-      app_file 'db/schema.rb', ''
+      app_file "db/schema.rb", ""
 
       assert_unsuccessful_run "models/user_test.rb", "Migrations are pending"
 
-      app_file 'db/schema.rb', <<-RUBY
+      app_file "db/schema.rb", <<-RUBY
         ActiveRecord::Schema.define(version: #{version}) do
           create_table :users do |t|
             t.string :name
@@ -92,7 +92,7 @@ module ApplicationTests
         end
       RUBY
 
-      app_file 'config/initializers/disable_maintain_test_schema.rb', <<-RUBY
+      app_file "config/initializers/disable_maintain_test_schema.rb", <<-RUBY
         Rails.application.config.active_record.maintain_test_schema = false
       RUBY
 
@@ -100,15 +100,15 @@ module ApplicationTests
 
       File.delete "#{app_path}/config/initializers/disable_maintain_test_schema.rb"
 
-      result = assert_successful_test_run('models/user_test.rb')
+      result = assert_successful_test_run("models/user_test.rb")
       assert !result.include?("create_table(:users)")
     end
 
     test "sql structure migrations" do
-      output  = script('generate model user name:string')
+      output  = script("generate model user name:string")
       version = output.match(/(\d+)_create_users\.rb/)[1]
 
-      app_file 'test/models/user_test.rb', <<-RUBY
+      app_file "test/models/user_test.rb", <<-RUBY
         require 'test_helper'
 
         class UserTest < ActiveSupport::TestCase
@@ -118,21 +118,21 @@ module ApplicationTests
         end
       RUBY
 
-      app_file 'db/structure.sql', ''
-      app_file 'config/initializers/enable_sql_schema_format.rb', <<-RUBY
+      app_file "db/structure.sql", ""
+      app_file "config/initializers/enable_sql_schema_format.rb", <<-RUBY
         Rails.application.config.active_record.schema_format = :sql
       RUBY
 
       assert_unsuccessful_run "models/user_test.rb", "Migrations are pending"
 
-      app_file 'db/structure.sql', <<-SQL
+      app_file "db/structure.sql", <<-SQL
         CREATE TABLE "schema_migrations" ("version" varchar(255) NOT NULL);
         CREATE UNIQUE INDEX "unique_schema_migrations" ON "schema_migrations" ("version");
         CREATE TABLE "users" ("id" INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, "name" varchar(255));
         INSERT INTO schema_migrations (version) VALUES ('#{version}');
       SQL
 
-      app_file 'config/initializers/disable_maintain_test_schema.rb', <<-RUBY
+      app_file "config/initializers/disable_maintain_test_schema.rb", <<-RUBY
         Rails.application.config.active_record.maintain_test_schema = false
       RUBY
 
@@ -140,14 +140,14 @@ module ApplicationTests
 
       File.delete "#{app_path}/config/initializers/disable_maintain_test_schema.rb"
 
-      assert_successful_test_run('models/user_test.rb')
+      assert_successful_test_run("models/user_test.rb")
     end
 
     test "sql structure migrations when adding column to existing table" do
-      output_1  = script('generate model user name:string')
+      output_1  = script("generate model user name:string")
       version_1 = output_1.match(/(\d+)_create_users\.rb/)[1]
 
-      app_file 'test/models/user_test.rb', <<-RUBY
+      app_file "test/models/user_test.rb", <<-RUBY
         require 'test_helper'
         class UserTest < ActiveSupport::TestCase
           test "user" do
@@ -156,23 +156,23 @@ module ApplicationTests
         end
       RUBY
 
-      app_file 'config/initializers/enable_sql_schema_format.rb', <<-RUBY
+      app_file "config/initializers/enable_sql_schema_format.rb", <<-RUBY
         Rails.application.config.active_record.schema_format = :sql
       RUBY
 
-      app_file 'db/structure.sql', <<-SQL
+      app_file "db/structure.sql", <<-SQL
         CREATE TABLE "schema_migrations" ("version" varchar(255) NOT NULL);
         CREATE UNIQUE INDEX "unique_schema_migrations" ON "schema_migrations" ("version");
         CREATE TABLE "users" ("id" INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, "name" varchar(255));
         INSERT INTO schema_migrations (version) VALUES ('#{version_1}');
       SQL
 
-      assert_successful_test_run('models/user_test.rb')
+      assert_successful_test_run("models/user_test.rb")
 
-      output_2  = script('generate migration add_email_to_users')
+      output_2  = script("generate migration add_email_to_users")
       version_2 = output_2.match(/(\d+)_add_email_to_users\.rb/)[1]
 
-      app_file 'test/models/user_test.rb', <<-RUBY
+      app_file "test/models/user_test.rb", <<-RUBY
         require 'test_helper'
 
         class UserTest < ActiveSupport::TestCase
@@ -182,7 +182,7 @@ module ApplicationTests
         end
       RUBY
 
-      app_file 'db/structure.sql', <<-SQL
+      app_file "db/structure.sql", <<-SQL
         CREATE TABLE "schema_migrations" ("version" varchar(255) NOT NULL);
         CREATE UNIQUE INDEX "unique_schema_migrations" ON "schema_migrations" ("version");
         CREATE TABLE "users" ("id" INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, "name" varchar(255), "email" varchar(255));
@@ -190,17 +190,17 @@ module ApplicationTests
         INSERT INTO schema_migrations (version) VALUES ('#{version_2}');
       SQL
 
-      assert_successful_test_run('models/user_test.rb')
+      assert_successful_test_run("models/user_test.rb")
     end
 
     # TODO: would be nice if we could detect the schema change automatically.
     # For now, the user has to synchronize the schema manually.
     # This test-case serves as a reminder for this use-case.
     test "manually synchronize test schema after rollback" do
-      output  = script('generate model user name:string')
+      output  = script("generate model user name:string")
       version = output.match(/(\d+)_create_users\.rb/)[1]
 
-      app_file 'test/models/user_test.rb', <<-RUBY
+      app_file "test/models/user_test.rb", <<-RUBY
         require 'test_helper'
 
         class UserTest < ActiveSupport::TestCase
@@ -209,7 +209,7 @@ module ApplicationTests
           end
         end
       RUBY
-      app_file 'db/schema.rb', <<-RUBY
+      app_file "db/schema.rb", <<-RUBY
         ActiveRecord::Schema.define(version: #{version}) do
           create_table :users do |t|
             t.string :name
@@ -220,7 +220,7 @@ module ApplicationTests
       assert_successful_test_run "models/user_test.rb"
 
       # Simulate `db:rollback` + edit of the migration file + `db:migrate`
-      app_file 'db/schema.rb', <<-RUBY
+      app_file "db/schema.rb", <<-RUBY
         ActiveRecord::Schema.define(version: #{version}) do
           create_table :users do |t|
             t.string :name
@@ -240,10 +240,10 @@ Expected: ["id", "name"]
     end
 
     test "hooks for plugins" do
-      output  = script('generate model user name:string')
+      output  = script("generate model user name:string")
       version = output.match(/(\d+)_create_users\.rb/)[1]
 
-      app_file 'lib/tasks/hooks.rake', <<-RUBY
+      app_file "lib/tasks/hooks.rake", <<-RUBY
         task :before_hook do
           has_user_table = ActiveRecord::Base.connection.table_exists?('users')
           puts "before: " + has_user_table.to_s
@@ -258,7 +258,7 @@ Expected: ["id", "name"]
           Rake::Task[:after_hook].invoke
         end
       RUBY
-      app_file 'test/models/user_test.rb', <<-RUBY
+      app_file "test/models/user_test.rb", <<-RUBY
         require 'test_helper'
         class UserTest < ActiveSupport::TestCase
           test "user" do
@@ -268,7 +268,7 @@ Expected: ["id", "name"]
       RUBY
 
       # Simulate `db:migrate`
-      app_file 'db/schema.rb', <<-RUBY
+      app_file "db/schema.rb", <<-RUBY
         ActiveRecord::Schema.define(version: #{version}) do
           create_table :users do |t|
             t.string :name
diff --git a/railties/test/application/url_generation_test.rb b/railties/test/application/url_generation_test.rb
index 6700323199..ced6c6b0a6 100644
--- a/railties/test/application/url_generation_test.rb
+++ b/railties/test/application/url_generation_test.rb
@@ -1,4 +1,4 @@
-require 'isolation/abstract_unit'
+require "isolation/abstract_unit"
 
 module ApplicationTests
   class UrlGenerationTest < ActiveSupport::TestCase
@@ -35,7 +35,7 @@ module ApplicationTests
         get "/" => "omg#index", as: :omg
       end
 
-      require 'rack/test'
+      require "rack/test"
       extend Rack::Test::Methods
 
       get "/"
@@ -47,7 +47,7 @@ module ApplicationTests
       require "action_controller/railtie"
       require "action_view/railtie"
 
-      relative_url = '/hello'
+      relative_url = "/hello"
       ENV["RAILS_RELATIVE_URL_ROOT"] = relative_url
       app = Class.new(Rails::Application)
       assert_equal relative_url, app.routes.relative_url_root
diff --git a/railties/test/backtrace_cleaner_test.rb b/railties/test/backtrace_cleaner_test.rb
index 1b23b0de91..17201d6f77 100644
--- a/railties/test/backtrace_cleaner_test.rb
+++ b/railties/test/backtrace_cleaner_test.rb
@@ -1,5 +1,5 @@
-require 'abstract_unit'
-require 'rails/backtrace_cleaner'
+require "abstract_unit"
+require "rails/backtrace_cleaner"
 
 class BacktraceCleanerTest < ActiveSupport::TestCase
   def setup
diff --git a/railties/test/code_statistics_calculator_test.rb b/railties/test/code_statistics_calculator_test.rb
index cecc3908b3..2dba3c6e96 100644
--- a/railties/test/code_statistics_calculator_test.rb
+++ b/railties/test/code_statistics_calculator_test.rb
@@ -1,12 +1,12 @@
-require 'abstract_unit'
-require 'rails/code_statistics_calculator'
+require "abstract_unit"
+require "rails/code_statistics_calculator"
 
 class CodeStatisticsCalculatorTest < ActiveSupport::TestCase
   def setup
     @code_statistics_calculator = CodeStatisticsCalculator.new
   end
 
-  test 'calculate statistics using #add_by_file_path' do
+  test "calculate statistics using #add_by_file_path" do
     code = <<-RUBY
       def foo
         puts 'foo'
@@ -14,7 +14,7 @@ class CodeStatisticsCalculatorTest < ActiveSupport::TestCase
       end
     RUBY
 
-    temp_file 'stats.rb', code do |path|
+    temp_file "stats.rb", code do |path|
       @code_statistics_calculator.add_by_file_path path
 
       assert_equal 4, @code_statistics_calculator.lines
@@ -24,7 +24,7 @@ class CodeStatisticsCalculatorTest < ActiveSupport::TestCase
     end
   end
 
-  test 'count number of methods in MiniTest file' do
+  test "count number of methods in MiniTest file" do
     code = <<-RUBY
       class FooTest < ActionController::TestCase
         test 'expectation' do
@@ -37,13 +37,13 @@ class CodeStatisticsCalculatorTest < ActiveSupport::TestCase
       end
     RUBY
 
-    temp_file 'foo_test.rb', code do |path|
+    temp_file "foo_test.rb", code do |path|
       @code_statistics_calculator.add_by_file_path path
       assert_equal 2, @code_statistics_calculator.methods
     end
   end
 
-  test 'add statistics to another using #add' do
+  test "add statistics to another using #add" do
     code_statistics_calculator_1 = CodeStatisticsCalculator.new(1, 2, 3, 4)
     @code_statistics_calculator.add(code_statistics_calculator_1)
 
@@ -61,7 +61,7 @@ class CodeStatisticsCalculatorTest < ActiveSupport::TestCase
     assert_equal 9, @code_statistics_calculator.methods
   end
 
-  test 'accumulate statistics using #add_by_io' do
+  test "accumulate statistics using #add_by_io" do
     code_statistics_calculator_1 = CodeStatisticsCalculator.new(1, 2, 3, 4)
     @code_statistics_calculator.add(code_statistics_calculator_1)
 
@@ -82,7 +82,7 @@ class CodeStatisticsCalculatorTest < ActiveSupport::TestCase
     assert_equal 6, @code_statistics_calculator.methods
   end
 
-  test 'calculate number of Ruby methods' do
+  test "calculate number of Ruby methods" do
     code = <<-'CODE'
       def foo
         puts 'foo'
@@ -101,7 +101,7 @@ class CodeStatisticsCalculatorTest < ActiveSupport::TestCase
     assert_equal 3, @code_statistics_calculator.methods
   end
 
-  test 'calculate Ruby LOCs' do
+  test "calculate Ruby LOCs" do
     code = <<-'CODE'
       def foo
         puts 'foo'
@@ -119,7 +119,7 @@ class CodeStatisticsCalculatorTest < ActiveSupport::TestCase
     assert_equal 5, @code_statistics_calculator.code_lines
   end
 
-  test 'calculate number of Ruby classes' do
+  test "calculate number of Ruby classes" do
     code = <<-'CODE'
       class Foo < Bar
         def foo
@@ -138,7 +138,7 @@ class CodeStatisticsCalculatorTest < ActiveSupport::TestCase
     assert_equal 2, @code_statistics_calculator.classes
   end
 
-  test 'skip Ruby comments' do
+  test "skip Ruby comments" do
     code = <<-'CODE'
 =begin
       class Foo
@@ -160,7 +160,7 @@ class CodeStatisticsCalculatorTest < ActiveSupport::TestCase
     assert_equal 0, @code_statistics_calculator.methods
   end
 
-  test 'calculate number of JS methods' do
+  test "calculate number of JS methods" do
     code = <<-'CODE'
       function foo(x, y, z) {
         doX();
@@ -179,7 +179,7 @@ class CodeStatisticsCalculatorTest < ActiveSupport::TestCase
     assert_equal 3, @code_statistics_calculator.methods
   end
 
-  test 'calculate JS LOCs' do
+  test "calculate JS LOCs" do
     code = <<-'CODE'
       function foo()
         alert('foo');
@@ -196,7 +196,7 @@ class CodeStatisticsCalculatorTest < ActiveSupport::TestCase
     assert_equal 4, @code_statistics_calculator.code_lines
   end
 
-  test 'skip JS comments' do
+  test "skip JS comments" do
     code = <<-'CODE'
       /*
        * var f = function () {
@@ -216,7 +216,7 @@ class CodeStatisticsCalculatorTest < ActiveSupport::TestCase
     assert_equal 0, @code_statistics_calculator.methods
   end
 
-  test 'calculate number of CoffeeScript methods' do
+  test "calculate number of CoffeeScript methods" do
     code = <<-'CODE'
       square = (x) -> x * x
 
@@ -235,7 +235,7 @@ class CodeStatisticsCalculatorTest < ActiveSupport::TestCase
     assert_equal 4, @code_statistics_calculator.methods
   end
 
-  test 'calculate CoffeeScript LOCs' do
+  test "calculate CoffeeScript LOCs" do
     code = <<-'CODE'
       # Assignment:
       number   = 42
@@ -256,7 +256,7 @@ class CodeStatisticsCalculatorTest < ActiveSupport::TestCase
     assert_equal 3, @code_statistics_calculator.code_lines
   end
 
-  test 'calculate number of CoffeeScript classes' do
+  test "calculate number of CoffeeScript classes" do
     code = <<-'CODE'
       class Animal
         constructor: (@name) ->
@@ -277,7 +277,7 @@ class CodeStatisticsCalculatorTest < ActiveSupport::TestCase
     assert_equal 2, @code_statistics_calculator.classes
   end
 
-  test 'skip CoffeeScript comments' do
+  test "skip CoffeeScript comments" do
     code = <<-'CODE'
 ###
 class Animal
@@ -299,7 +299,7 @@ class Animal
     assert_equal 0, @code_statistics_calculator.methods
   end
 
-  test 'count rake tasks' do
+  test "count rake tasks" do
     code = <<-'CODE'
       task :test_task do
         puts 'foo'
@@ -317,7 +317,7 @@ class Animal
 
   private
     def temp_file(name, content)
-      dir = File.expand_path '../fixtures/tmp', __FILE__
+      dir = File.expand_path "../fixtures/tmp", __FILE__
       path = "#{dir}/#{name}"
 
       FileUtils.mkdir_p dir
diff --git a/railties/test/code_statistics_test.rb b/railties/test/code_statistics_test.rb
index 4d80901217..2c0db2fd0a 100644
--- a/railties/test/code_statistics_test.rb
+++ b/railties/test/code_statistics_test.rb
@@ -1,10 +1,10 @@
-require 'abstract_unit'
-require 'rails/code_statistics'
+require "abstract_unit"
+require "rails/code_statistics"
 
 class CodeStatisticsTest < ActiveSupport::TestCase
   def setup
-    @tmp_path = File.expand_path(File.join(File.dirname(__FILE__), 'fixtures', 'tmp'))
-    @dir_js   = File.join(@tmp_path, 'lib.js')
+    @tmp_path = File.expand_path(File.join(File.dirname(__FILE__), "fixtures", "tmp"))
+    @dir_js   = File.join(@tmp_path, "lib.js")
     FileUtils.mkdir_p(@dir_js)
   end
 
@@ -12,21 +12,21 @@ class CodeStatisticsTest < ActiveSupport::TestCase
     FileUtils.rm_rf(@tmp_path)
   end
 
-  test 'ignores directories that happen to have source files extensions' do
+  test "ignores directories that happen to have source files extensions" do
     assert_nothing_raised do
-      @code_statistics = CodeStatistics.new(['tmp dir', @tmp_path])
+      @code_statistics = CodeStatistics.new(["tmp dir", @tmp_path])
     end
   end
 
-  test 'ignores hidden files' do
-    File.write File.join(@tmp_path, '.example.rb'), <<-CODE
+  test "ignores hidden files" do
+    File.write File.join(@tmp_path, ".example.rb"), <<-CODE
       def foo
         puts 'foo'
       end
     CODE
 
     assert_nothing_raised do
-      CodeStatistics.new(['hidden file', @tmp_path])
+      CodeStatistics.new(["hidden file", @tmp_path])
     end
   end
 
diff --git a/railties/test/commands/console_test.rb b/railties/test/commands/console_test.rb
index de0cf0ba9e..3f75dc8d58 100644
--- a/railties/test/commands/console_test.rb
+++ b/railties/test/commands/console_test.rb
@@ -1,6 +1,6 @@
-require 'abstract_unit'
-require 'env_helpers'
-require 'rails/commands/console'
+require "abstract_unit"
+require "env_helpers"
+require "rails/commands/console"
 
 class Rails::ConsoleTest < ActiveSupport::TestCase
   include EnvHelpers
@@ -64,52 +64,52 @@ class Rails::ConsoleTest < ActiveSupport::TestCase
   end
 
   def test_default_environment_with_rails_env
-    with_rails_env 'special-production' do
+    with_rails_env "special-production" do
       start
       assert_match(/\sspecial-production\s/, output)
     end
   end
 
   def test_default_environment_with_rack_env
-    with_rack_env 'production' do
+    with_rack_env "production" do
       start
       assert_match(/\sproduction\s/, output)
     end
   end
 
   def test_e_option
-    start ['-e', 'special-production']
+    start ["-e", "special-production"]
     assert_match(/\sspecial-production\s/, output)
   end
 
   def test_environment_option
-    start ['--environment=special-production']
+    start ["--environment=special-production"]
     assert_match(/\sspecial-production\s/, output)
   end
 
   def test_rails_env_is_production_when_first_argument_is_p
-    start ['p']
+    start ["p"]
     assert_match(/\sproduction\s/, output)
   end
 
   def test_rails_env_is_test_when_first_argument_is_t
-    start ['t']
+    start ["t"]
     assert_match(/\stest\s/, output)
   end
 
   def test_rails_env_is_development_when_argument_is_d
-    start ['d']
+    start ["d"]
     assert_match(/\sdevelopment\s/, output)
   end
 
   def test_rails_env_is_dev_when_argument_is_dev_and_dev_env_is_present
     stubbed_console = Class.new(Rails::Console) do
       def available_environments
-        ['dev']
+        ["dev"]
       end
     end
-    options = stubbed_console.parse_arguments(['dev'])
-    assert_match('dev', options[:environment])
+    options = stubbed_console.parse_arguments(["dev"])
+    assert_match("dev", options[:environment])
   end
 
   attr_reader :output
diff --git a/railties/test/commands/dbconsole_test.rb b/railties/test/commands/dbconsole_test.rb
index a5aa6c14a2..128b930528 100644
--- a/railties/test/commands/dbconsole_test.rb
+++ b/railties/test/commands/dbconsole_test.rb
@@ -1,16 +1,16 @@
-require 'abstract_unit'
-require 'minitest/mock'
-require 'rails/commands/dbconsole'
+require "abstract_unit"
+require "minitest/mock"
+require "rails/commands/dbconsole"
 
 class Rails::DBConsoleTest < ActiveSupport::TestCase
 
 
   def setup
-    Rails::DBConsole.const_set('APP_PATH', 'rails/all')
+    Rails::DBConsole.const_set("APP_PATH", "rails/all")
   end
 
   def teardown
-    Rails::DBConsole.send(:remove_const, 'APP_PATH')
+    Rails::DBConsole.send(:remove_const, "APP_PATH")
     %w[PGUSER PGHOST PGPORT PGPASSWORD DATABASE_URL].each{|key| ENV.delete(key)}
   end
 
@@ -41,7 +41,7 @@ class Rails::DBConsoleTest < ActiveSupport::TestCase
   end
 
   def test_config_with_database_url_only
-    ENV['DATABASE_URL'] = 'postgresql://foo:bar@localhost:9000/foo_test?pool=5&timeout=3000'
+    ENV["DATABASE_URL"] = "postgresql://foo:bar@localhost:9000/foo_test?pool=5&timeout=3000"
     expected = {
       "adapter"  => "postgresql",
       "host"     => "localhost",
@@ -60,7 +60,7 @@ class Rails::DBConsoleTest < ActiveSupport::TestCase
 
   def test_config_choose_database_url_if_exists
     host = "database-url-host.com"
-    ENV['DATABASE_URL'] = "postgresql://foo:bar@#{host}:9000/foo_test?pool=5&timeout=3000"
+    ENV["DATABASE_URL"] = "postgresql://foo:bar@#{host}:9000/foo_test?pool=5&timeout=3000"
     sample_config = {
       "test" => {
         "adapter"  => "postgresql",
@@ -81,143 +81,143 @@ class Rails::DBConsoleTest < ActiveSupport::TestCase
   def test_env
     assert_equal "test", Rails::DBConsole.new.environment
 
-    ENV['RAILS_ENV'] = nil
-    ENV['RACK_ENV'] = nil
+    ENV["RAILS_ENV"] = nil
+    ENV["RACK_ENV"] = nil
 
     Rails.stub(:respond_to?, false) do
       assert_equal "development", Rails::DBConsole.new.environment
 
-      ENV['RACK_ENV'] = "rack_env"
+      ENV["RACK_ENV"] = "rack_env"
       assert_equal "rack_env", Rails::DBConsole.new.environment
 
-      ENV['RAILS_ENV'] = "rails_env"
+      ENV["RAILS_ENV"] = "rails_env"
       assert_equal "rails_env", Rails::DBConsole.new.environment
     end
   ensure
-    ENV['RAILS_ENV'] = "test"
-    ENV['RACK_ENV'] = nil
+    ENV["RAILS_ENV"] = "test"
+    ENV["RACK_ENV"] = nil
   end
 
   def test_rails_env_is_development_when_argument_is_dev
-    Rails::DBConsole.stub(:available_environments, ['development', 'test']) do
-      options = Rails::DBConsole.send(:parse_arguments, ['dev'])
-      assert_match('development', options[:environment])
+    Rails::DBConsole.stub(:available_environments, ["development", "test"]) do
+      options = Rails::DBConsole.send(:parse_arguments, ["dev"])
+      assert_match("development", options[:environment])
     end
   end
 
   def test_rails_env_is_dev_when_argument_is_dev_and_dev_env_is_present
-    Rails::DBConsole.stub(:available_environments, ['dev']) do
-      options = Rails::DBConsole.send(:parse_arguments, ['dev'])
-      assert_match('dev', options[:environment])
+    Rails::DBConsole.stub(:available_environments, ["dev"]) do
+      options = Rails::DBConsole.send(:parse_arguments, ["dev"])
+      assert_match("dev", options[:environment])
     end
   end
 
   def test_mysql
-    start(adapter: 'mysql2', database: 'db')
+    start(adapter: "mysql2", database: "db")
     assert !aborted
-    assert_equal [%w[mysql mysql5], 'db'], dbconsole.find_cmd_and_exec_args
+    assert_equal [%w[mysql mysql5], "db"], dbconsole.find_cmd_and_exec_args
   end
 
   def test_mysql_full
-    start(adapter: 'mysql2', database: 'db', host: 'locahost', port: 1234, socket: 'socket', username: 'user', password: 'qwerty', encoding: 'UTF-8')
+    start(adapter: "mysql2", database: "db", host: "locahost", port: 1234, socket: "socket", username: "user", password: "qwerty", encoding: "UTF-8")
     assert !aborted
-    assert_equal [%w[mysql mysql5], '--host=locahost', '--port=1234', '--socket=socket', '--user=user', '--default-character-set=UTF-8', '-p', 'db'], dbconsole.find_cmd_and_exec_args
+    assert_equal [%w[mysql mysql5], "--host=locahost", "--port=1234", "--socket=socket", "--user=user", "--default-character-set=UTF-8", "-p", "db"], dbconsole.find_cmd_and_exec_args
   end
 
   def test_mysql_include_password
-    start({adapter: 'mysql2', database: 'db', username: 'user', password: 'qwerty'}, ['-p'])
+    start({adapter: "mysql2", database: "db", username: "user", password: "qwerty"}, ["-p"])
     assert !aborted
-    assert_equal [%w[mysql mysql5], '--user=user', '--password=qwerty', 'db'], dbconsole.find_cmd_and_exec_args
+    assert_equal [%w[mysql mysql5], "--user=user", "--password=qwerty", "db"], dbconsole.find_cmd_and_exec_args
   end
 
   def test_postgresql
-    start(adapter: 'postgresql', database: 'db')
+    start(adapter: "postgresql", database: "db")
     assert !aborted
-    assert_equal ['psql', 'db'], dbconsole.find_cmd_and_exec_args
+    assert_equal ["psql", "db"], dbconsole.find_cmd_and_exec_args
   end
 
   def test_postgresql_full
-    start(adapter: 'postgresql', database: 'db', username: 'user', password: 'q1w2e3', host: 'host', port: 5432)
+    start(adapter: "postgresql", database: "db", username: "user", password: "q1w2e3", host: "host", port: 5432)
     assert !aborted
-    assert_equal ['psql', 'db'], dbconsole.find_cmd_and_exec_args
-    assert_equal 'user', ENV['PGUSER']
-    assert_equal 'host', ENV['PGHOST']
-    assert_equal '5432', ENV['PGPORT']
-    assert_not_equal 'q1w2e3', ENV['PGPASSWORD']
+    assert_equal ["psql", "db"], dbconsole.find_cmd_and_exec_args
+    assert_equal "user", ENV["PGUSER"]
+    assert_equal "host", ENV["PGHOST"]
+    assert_equal "5432", ENV["PGPORT"]
+    assert_not_equal "q1w2e3", ENV["PGPASSWORD"]
   end
 
   def test_postgresql_include_password
-    start({adapter: 'postgresql', database: 'db', username: 'user', password: 'q1w2e3'}, ['-p'])
+    start({adapter: "postgresql", database: "db", username: "user", password: "q1w2e3"}, ["-p"])
     assert !aborted
-    assert_equal ['psql', 'db'], dbconsole.find_cmd_and_exec_args
-    assert_equal 'user', ENV['PGUSER']
-    assert_equal 'q1w2e3', ENV['PGPASSWORD']
+    assert_equal ["psql", "db"], dbconsole.find_cmd_and_exec_args
+    assert_equal "user", ENV["PGUSER"]
+    assert_equal "q1w2e3", ENV["PGPASSWORD"]
   end
 
   def test_sqlite3
-    start(adapter: 'sqlite3', database: 'db.sqlite3')
+    start(adapter: "sqlite3", database: "db.sqlite3")
     assert !aborted
-    assert_equal ['sqlite3', Rails.root.join('db.sqlite3').to_s], dbconsole.find_cmd_and_exec_args
+    assert_equal ["sqlite3", Rails.root.join("db.sqlite3").to_s], dbconsole.find_cmd_and_exec_args
   end
 
   def test_sqlite3_mode
-    start({adapter: 'sqlite3', database: 'db.sqlite3'}, ['--mode', 'html'])
+    start({adapter: "sqlite3", database: "db.sqlite3"}, ["--mode", "html"])
     assert !aborted
-    assert_equal ['sqlite3', '-html', Rails.root.join('db.sqlite3').to_s], dbconsole.find_cmd_and_exec_args
+    assert_equal ["sqlite3", "-html", Rails.root.join("db.sqlite3").to_s], dbconsole.find_cmd_and_exec_args
   end
 
   def test_sqlite3_header
-    start({adapter: 'sqlite3', database: 'db.sqlite3'}, ['--header'])
-    assert_equal ['sqlite3', '-header', Rails.root.join('db.sqlite3').to_s], dbconsole.find_cmd_and_exec_args
+    start({adapter: "sqlite3", database: "db.sqlite3"}, ["--header"])
+    assert_equal ["sqlite3", "-header", Rails.root.join("db.sqlite3").to_s], dbconsole.find_cmd_and_exec_args
   end
 
   def test_sqlite3_db_absolute_path
-    start(adapter: 'sqlite3', database: '/tmp/db.sqlite3')
+    start(adapter: "sqlite3", database: "/tmp/db.sqlite3")
     assert !aborted
-    assert_equal ['sqlite3', '/tmp/db.sqlite3'], dbconsole.find_cmd_and_exec_args
+    assert_equal ["sqlite3", "/tmp/db.sqlite3"], dbconsole.find_cmd_and_exec_args
   end
 
   def test_sqlite3_db_without_defined_rails_root
     Rails.stub(:respond_to?, false) do
-      start(adapter: 'sqlite3', database: 'config/db.sqlite3')
+      start(adapter: "sqlite3", database: "config/db.sqlite3")
       assert !aborted
-      assert_equal ['sqlite3', Rails.root.join('../config/db.sqlite3').to_s], dbconsole.find_cmd_and_exec_args
+      assert_equal ["sqlite3", Rails.root.join("../config/db.sqlite3").to_s], dbconsole.find_cmd_and_exec_args
     end
   end
 
   def test_oracle
-    start(adapter: 'oracle', database: 'db', username: 'user', password: 'secret')
+    start(adapter: "oracle", database: "db", username: "user", password: "secret")
     assert !aborted
-    assert_equal ['sqlplus', 'user@db'], dbconsole.find_cmd_and_exec_args
+    assert_equal ["sqlplus", "user@db"], dbconsole.find_cmd_and_exec_args
   end
 
   def test_oracle_include_password
-    start({adapter: 'oracle', database: 'db', username: 'user', password: 'secret'}, ['-p'])
+    start({adapter: "oracle", database: "db", username: "user", password: "secret"}, ["-p"])
     assert !aborted
-    assert_equal ['sqlplus', 'user/secret@db'], dbconsole.find_cmd_and_exec_args
+    assert_equal ["sqlplus", "user/secret@db"], dbconsole.find_cmd_and_exec_args
   end
 
   def test_unknown_command_line_client
-    start(adapter: 'unknown', database: 'db')
+    start(adapter: "unknown", database: "db")
     assert aborted
     assert_match(/Unknown command-line client for db/, output)
   end
 
   def test_print_help_short
     stdout = capture(:stdout) do
-      start({}, ['-h'])
+      start({}, ["-h"])
     end
     assert aborted
-    assert_equal '', output
+    assert_equal "", output
     assert_match(/Usage:.*dbconsole/, stdout)
   end
 
   def test_print_help_long
     stdout = capture(:stdout) do
-      start({}, ['--help'])
+      start({}, ["--help"])
     end
     assert aborted
-    assert_equal '', output
+    assert_equal "", output
     assert_match(/Usage:.*dbconsole/, stdout)
   end
 
diff --git a/railties/test/commands/server_test.rb b/railties/test/commands/server_test.rb
index b9a48bbf98..c1ec73d95c 100644
--- a/railties/test/commands/server_test.rb
+++ b/railties/test/commands/server_test.rb
@@ -1,6 +1,6 @@
-require 'abstract_unit'
-require 'env_helpers'
-require 'rails/commands/server'
+require "abstract_unit"
+require "env_helpers"
+require "rails/commands/server"
 
 class Rails::ServerTest < ActiveSupport::TestCase
   include EnvHelpers
@@ -8,14 +8,14 @@ class Rails::ServerTest < ActiveSupport::TestCase
   def test_environment_with_server_option
     args    = ["thin", "-e", "production"]
     options = Rails::Server::Options.new.parse!(args)
-    assert_equal 'production', options[:environment]
-    assert_equal 'thin', options[:server]
+    assert_equal "production", options[:environment]
+    assert_equal "thin", options[:server]
   end
 
   def test_environment_without_server_option
     args    = ["-e", "production"]
     options = Rails::Server::Options.new.parse!(args)
-    assert_equal 'production', options[:environment]
+    assert_equal "production", options[:environment]
     assert_nil options[:server]
   end
 
@@ -23,23 +23,23 @@ class Rails::ServerTest < ActiveSupport::TestCase
     args    = ["thin"]
     options = Rails::Server::Options.new.parse!(args)
     assert_nil options[:environment]
-    assert_equal 'thin', options[:server]
+    assert_equal "thin", options[:server]
   end
 
   def test_environment_with_rails_env
     with_rack_env nil do
-      with_rails_env 'production' do
+      with_rails_env "production" do
         server = Rails::Server.new
-        assert_equal 'production', server.options[:environment]
+        assert_equal "production", server.options[:environment]
       end
     end
   end
 
   def test_environment_with_rack_env
     with_rails_env nil do
-      with_rack_env 'production' do
+      with_rack_env "production" do
         server = Rails::Server.new
-        assert_equal 'production', server.options[:environment]
+        assert_equal "production", server.options[:environment]
       end
     end
   end
@@ -90,25 +90,25 @@ class Rails::ServerTest < ActiveSupport::TestCase
         options = Rails::Server::Options.new.parse!(args)
         assert_equal false, options[:log_stdout]
 
-        with_rack_env 'development' do
+        with_rack_env "development" do
           args    = []
           options = Rails::Server::Options.new.parse!(args)
           assert_equal true, options[:log_stdout]
         end
 
-        with_rack_env 'production' do
+        with_rack_env "production" do
           args    = []
           options = Rails::Server::Options.new.parse!(args)
           assert_equal false, options[:log_stdout]
         end
 
-        with_rails_env 'development' do
+        with_rails_env "development" do
           args    = []
           options = Rails::Server::Options.new.parse!(args)
           assert_equal true, options[:log_stdout]
         end
 
-        with_rails_env 'production' do
+        with_rails_env "production" do
           args    = []
           options = Rails::Server::Options.new.parse!(args)
           assert_equal false, options[:log_stdout]
diff --git a/railties/test/configuration/middleware_stack_proxy_test.rb b/railties/test/configuration/middleware_stack_proxy_test.rb
index d5072614cf..586982c8dc 100644
--- a/railties/test/configuration/middleware_stack_proxy_test.rb
+++ b/railties/test/configuration/middleware_stack_proxy_test.rb
@@ -1,8 +1,8 @@
-require 'active_support'
-require 'active_support/testing/autorun'
-require 'rails/configuration'
-require 'active_support/test_case'
-require 'minitest/mock'
+require "active_support"
+require "active_support/testing/autorun"
+require "rails/configuration"
+require "active_support/test_case"
+require "minitest/mock"
 
 module Rails
   module Configuration
diff --git a/railties/test/engine_test.rb b/railties/test/engine_test.rb
index f46fb748f5..248afa2d2c 100644
--- a/railties/test/engine_test.rb
+++ b/railties/test/engine_test.rb
@@ -1,4 +1,4 @@
-require 'abstract_unit'
+require "abstract_unit"
 
 class EngineTest < ActiveSupport::TestCase
   test "reports routes as available only if they're actually present" do
diff --git a/railties/test/env_helpers.rb b/railties/test/env_helpers.rb
index 330fe150ca..68366b336f 100644
--- a/railties/test/env_helpers.rb
+++ b/railties/test/env_helpers.rb
@@ -1,12 +1,12 @@
-require 'rails'
+require "rails"
 
 module EnvHelpers
   private
 
   def with_rails_env(env)
     Rails.instance_variable_set :@_env, nil
-    switch_env 'RAILS_ENV', env do
-      switch_env 'RACK_ENV', nil do
+    switch_env "RAILS_ENV", env do
+      switch_env "RACK_ENV", nil do
         yield
       end
     end
@@ -14,8 +14,8 @@ module EnvHelpers
 
   def with_rack_env(env)
     Rails.instance_variable_set :@_env, nil
-    switch_env 'RACK_ENV', env do
-      switch_env 'RAILS_ENV', nil do
+    switch_env "RACK_ENV", env do
+      switch_env "RAILS_ENV", nil do
         yield
       end
     end
diff --git a/railties/test/fixtures/lib/generators/active_record/fixjour_generator.rb b/railties/test/fixtures/lib/generators/active_record/fixjour_generator.rb
index a7d079a1bc..1139350b94 100644
--- a/railties/test/fixtures/lib/generators/active_record/fixjour_generator.rb
+++ b/railties/test/fixtures/lib/generators/active_record/fixjour_generator.rb
@@ -1,4 +1,4 @@
-require 'rails/generators/active_record'
+require "rails/generators/active_record"
 
 module ActiveRecord
   module Generators
diff --git a/railties/test/fixtures/lib/generators/usage_template/usage_template_generator.rb b/railties/test/fixtures/lib/generators/usage_template/usage_template_generator.rb
index 078b0f9412..21b0ff6c28 100644
--- a/railties/test/fixtures/lib/generators/usage_template/usage_template_generator.rb
+++ b/railties/test/fixtures/lib/generators/usage_template/usage_template_generator.rb
@@ -1,4 +1,4 @@
-require 'rails/generators'
+require "rails/generators"
 
 class UsageTemplateGenerator < Rails::Generators::Base
   source_root File.expand_path("templates", File.dirname(__FILE__))
diff --git a/railties/test/generators/actions_test.rb b/railties/test/generators/actions_test.rb
index 3b2b3c37d0..c15eab1df3 100644
--- a/railties/test/generators/actions_test.rb
+++ b/railties/test/generators/actions_test.rb
@@ -1,6 +1,6 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/rails/app/app_generator'
-require 'env_helpers'
+require "generators/generators_test_helper"
+require "rails/generators/rails/app/app_generator"
+require "env_helpers"
 
 class ActionsTest < Rails::Generators::TestCase
   include GeneratorsTestHelper
@@ -19,98 +19,98 @@ class ActionsTest < Rails::Generators::TestCase
   end
 
   def test_invoke_other_generator_with_shortcut
-    action :invoke, 'model', ['my_model']
-    assert_file 'app/models/my_model.rb', /MyModel/
+    action :invoke, "model", ["my_model"]
+    assert_file "app/models/my_model.rb", /MyModel/
   end
 
   def test_invoke_other_generator_with_full_namespace
-    action :invoke, 'rails:model', ['my_model']
-    assert_file 'app/models/my_model.rb', /MyModel/
+    action :invoke, "rails:model", ["my_model"]
+    assert_file "app/models/my_model.rb", /MyModel/
   end
 
   def test_create_file_should_write_data_to_file_path
-    action :create_file, 'lib/test_file.rb', 'heres test data'
-    assert_file 'lib/test_file.rb', 'heres test data'
+    action :create_file, "lib/test_file.rb", "heres test data"
+    assert_file "lib/test_file.rb", "heres test data"
   end
 
   def test_create_file_should_write_block_contents_to_file_path
-    action(:create_file, 'lib/test_file.rb'){ 'heres block data' }
-    assert_file 'lib/test_file.rb', 'heres block data'
+    action(:create_file, "lib/test_file.rb"){ "heres block data" }
+    assert_file "lib/test_file.rb", "heres block data"
   end
 
   def test_add_source_adds_source_to_gemfile
     run_generator
-    action :add_source, 'http://gems.github.com'
-    assert_file 'Gemfile', /source 'http:\/\/gems\.github\.com'/
+    action :add_source, "http://gems.github.com"
+    assert_file "Gemfile", /source 'http:\/\/gems\.github\.com'/
   end
 
   def test_add_source_with_block_adds_source_to_gemfile_with_gem
     run_generator
-    action :add_source, 'http://gems.github.com' do
-      gem 'rspec-rails'
+    action :add_source, "http://gems.github.com" do
+      gem "rspec-rails"
     end
-    assert_file 'Gemfile', /source 'http:\/\/gems\.github\.com' do\n  gem 'rspec-rails'\nend/
+    assert_file "Gemfile", /source 'http:\/\/gems\.github\.com' do\n  gem 'rspec-rails'\nend/
   end
 
   def test_add_source_with_block_adds_source_to_gemfile_after_gem
     run_generator
-    action :gem, 'will-paginate'
-    action :add_source, 'http://gems.github.com' do
-      gem 'rspec-rails'
+    action :gem, "will-paginate"
+    action :add_source, "http://gems.github.com" do
+      gem "rspec-rails"
     end
-    assert_file 'Gemfile', /gem 'will-paginate'\nsource 'http:\/\/gems\.github\.com' do\n  gem 'rspec-rails'\nend/
+    assert_file "Gemfile", /gem 'will-paginate'\nsource 'http:\/\/gems\.github\.com' do\n  gem 'rspec-rails'\nend/
   end
 
   def test_gem_should_put_gem_dependency_in_gemfile
     run_generator
-    action :gem, 'will-paginate'
-    assert_file 'Gemfile', /gem 'will\-paginate'/
+    action :gem, "will-paginate"
+    assert_file "Gemfile", /gem 'will\-paginate'/
   end
 
   def test_gem_with_version_should_include_version_in_gemfile
     run_generator
 
-    action :gem, 'rspec', '>=2.0.0.a5'
+    action :gem, "rspec", ">=2.0.0.a5"
 
-    assert_file 'Gemfile', /gem 'rspec', '>=2.0.0.a5'/
+    assert_file "Gemfile", /gem 'rspec', '>=2.0.0.a5'/
   end
 
   def test_gem_should_insert_on_separate_lines
     run_generator
 
-    File.open('Gemfile', 'a') {|f| f.write('# Some content...') }
+    File.open("Gemfile", "a") {|f| f.write("# Some content...") }
 
-    action :gem, 'rspec'
-    action :gem, 'rspec-rails'
+    action :gem, "rspec"
+    action :gem, "rspec-rails"
 
-    assert_file 'Gemfile', /^gem 'rspec'$/
-    assert_file 'Gemfile', /^gem 'rspec-rails'$/
+    assert_file "Gemfile", /^gem 'rspec'$/
+    assert_file "Gemfile", /^gem 'rspec-rails'$/
   end
 
   def test_gem_should_include_options
     run_generator
 
-    action :gem, 'rspec', github: 'dchelimsky/rspec', tag: '1.2.9.rc1'
+    action :gem, "rspec", github: "dchelimsky/rspec", tag: "1.2.9.rc1"
 
-    assert_file 'Gemfile', /gem 'rspec', github: 'dchelimsky\/rspec', tag: '1\.2\.9\.rc1'/
+    assert_file "Gemfile", /gem 'rspec', github: 'dchelimsky\/rspec', tag: '1\.2\.9\.rc1'/
   end
 
   def test_gem_with_non_string_options
     run_generator
 
-    action :gem, 'rspec', require: false
-    action :gem, 'rspec-rails', group: [:development, :test]
+    action :gem, "rspec", require: false
+    action :gem, "rspec-rails", group: [:development, :test]
 
-    assert_file 'Gemfile', /^gem 'rspec', require: false$/
-    assert_file 'Gemfile', /^gem 'rspec-rails', group: \[:development, :test\]$/
+    assert_file "Gemfile", /^gem 'rspec', require: false$/
+    assert_file "Gemfile", /^gem 'rspec-rails', group: \[:development, :test\]$/
   end
 
   def test_gem_falls_back_to_inspect_if_string_contains_single_quote
     run_generator
 
-    action :gem, 'rspec', ">=2.0'0"
+    action :gem, "rspec", ">=2.0'0"
 
-    assert_file 'Gemfile', /^gem 'rspec', ">=2\.0'0"$/
+    assert_file "Gemfile", /^gem 'rspec', ">=2\.0'0"$/
   end
 
   def test_gem_works_even_if_frozen_string_is_passed_as_argument
@@ -118,34 +118,34 @@ class ActionsTest < Rails::Generators::TestCase
 
     action :gem, "frozen_gem".freeze, "1.0.0".freeze
 
-    assert_file 'Gemfile', /^gem 'frozen_gem', '1.0.0'$/
+    assert_file "Gemfile", /^gem 'frozen_gem', '1.0.0'$/
   end
 
   def test_gem_group_should_wrap_gems_in_a_group
     run_generator
 
     action :gem_group, :development, :test do
-      gem 'rspec-rails'
+      gem "rspec-rails"
     end
 
     action :gem_group, :test do
-      gem 'fakeweb'
+      gem "fakeweb"
     end
 
-    assert_file 'Gemfile', /\ngroup :development, :test do\n  gem 'rspec-rails'\nend\n\ngroup :test do\n  gem 'fakeweb'\nend/
+    assert_file "Gemfile", /\ngroup :development, :test do\n  gem 'rspec-rails'\nend\n\ngroup :test do\n  gem 'fakeweb'\nend/
   end
 
   def test_environment_should_include_data_in_environment_initializer_block
     run_generator
     autoload_paths = 'config.autoload_paths += %w["#{Rails.root}/app/extras"]'
     action :environment, autoload_paths
-    assert_file 'config/application.rb', /  class Application < Rails::Application\n    #{Regexp.escape(autoload_paths)}/
+    assert_file "config/application.rb", /  class Application < Rails::Application\n    #{Regexp.escape(autoload_paths)}/
   end
 
   def test_environment_should_include_data_in_environment_initializer_block_with_env_option
     run_generator
     autoload_paths = 'config.autoload_paths += %w["#{Rails.root}/app/extras"]'
-    action :environment, autoload_paths, env: 'development'
+    action :environment, autoload_paths, env: "development"
     assert_file "config/environments/development.rb", /Rails\.application\.configure do\n  #{Regexp.escape(autoload_paths)}/
   end
 
@@ -153,80 +153,80 @@ class ActionsTest < Rails::Generators::TestCase
     run_generator
 
     action :environment do
-      _ = '# This wont be added'# assignment to silence parse-time warning "unused literal ignored"
-      '# This will be added'
+      _ = "# This wont be added"# assignment to silence parse-time warning "unused literal ignored"
+      "# This will be added"
     end
 
-    assert_file 'config/application.rb' do |content|
+    assert_file "config/application.rb" do |content|
       assert_match(/# This will be added/, content)
       assert_no_match(/# This wont be added/, content)
     end
   end
 
   def test_git_with_symbol_should_run_command_using_git_scm
-    assert_called_with(generator, :run, ['git init']) do
+    assert_called_with(generator, :run, ["git init"]) do
       action :git, :init
     end
   end
 
   def test_git_with_hash_should_run_each_command_using_git_scm
     assert_called_with(generator, :run, [ ["git rm README"], ["git add ."] ]) do
-      action :git, rm: 'README', add: '.'
+      action :git, rm: "README", add: "."
     end
   end
 
   def test_vendor_should_write_data_to_file_in_vendor
-    action :vendor, 'vendor_file.rb', '# vendor data'
-    assert_file 'vendor/vendor_file.rb', '# vendor data'
+    action :vendor, "vendor_file.rb", "# vendor data"
+    assert_file "vendor/vendor_file.rb", "# vendor data"
   end
 
   def test_lib_should_write_data_to_file_in_lib
-    action :lib, 'my_library.rb', 'class MyLibrary'
-    assert_file 'lib/my_library.rb', 'class MyLibrary'
+    action :lib, "my_library.rb", "class MyLibrary"
+    assert_file "lib/my_library.rb", "class MyLibrary"
   end
 
   def test_rakefile_should_write_date_to_file_in_lib_tasks
-    action :rakefile, 'myapp.rake', 'task run: [:environment]'
-    assert_file 'lib/tasks/myapp.rake', 'task run: [:environment]'
+    action :rakefile, "myapp.rake", "task run: [:environment]"
+    assert_file "lib/tasks/myapp.rake", "task run: [:environment]"
   end
 
   def test_initializer_should_write_date_to_file_in_config_initializers
-    action :initializer, 'constants.rb', 'MY_CONSTANT = 42'
-    assert_file 'config/initializers/constants.rb', 'MY_CONSTANT = 42'
+    action :initializer, "constants.rb", "MY_CONSTANT = 42"
+    assert_file "config/initializers/constants.rb", "MY_CONSTANT = 42"
   end
 
   def test_generate_should_run_script_generate_with_argument_and_options
-    assert_called_with(generator, :run_ruby_script, ['bin/rails generate model MyModel', verbose: false]) do
-      action :generate, 'model', 'MyModel'
+    assert_called_with(generator, :run_ruby_script, ["bin/rails generate model MyModel", verbose: false]) do
+      action :generate, "model", "MyModel"
     end
   end
 
   def test_rails_should_run_rake_command_with_default_env
     assert_called_with(generator, :run, ["rake log:clear RAILS_ENV=development", verbose: false]) do
       with_rails_env nil do
-        action :rake, 'log:clear'
+        action :rake, "log:clear"
       end
     end
   end
 
   def test_rails_with_env_option_should_run_rake_command_in_env
-    assert_called_with(generator, :run, ['rake log:clear RAILS_ENV=production', verbose: false]) do
-      action :rake, 'log:clear', env: 'production'
+    assert_called_with(generator, :run, ["rake log:clear RAILS_ENV=production", verbose: false]) do
+      action :rake, "log:clear", env: "production"
     end
   end
 
   test "rails command with RAILS_ENV variable should run rake command in env" do
-    assert_called_with(generator, :run, ['rake log:clear RAILS_ENV=production', verbose: false]) do
+    assert_called_with(generator, :run, ["rake log:clear RAILS_ENV=production", verbose: false]) do
       with_rails_env "production" do
-        action :rake, 'log:clear'
+        action :rake, "log:clear"
       end
     end
   end
 
   test "env option should win over RAILS_ENV variable when running rake" do
-    assert_called_with(generator, :run, ['rake log:clear RAILS_ENV=production', verbose: false]) do
+    assert_called_with(generator, :run, ["rake log:clear RAILS_ENV=production", verbose: false]) do
       with_rails_env "staging" do
-        action :rake, 'log:clear', env: 'production'
+        action :rake, "log:clear", env: "production"
       end
     end
   end
@@ -234,7 +234,7 @@ class ActionsTest < Rails::Generators::TestCase
   test "rails command with sudo option should run rake command with sudo" do
     assert_called_with(generator, :run, ["sudo rake log:clear RAILS_ENV=development", verbose: false]) do
       with_rails_env nil do
-        action :rake, 'log:clear', sudo: true
+        action :rake, "log:clear", sudo: true
       end
     end
   end
@@ -242,29 +242,29 @@ class ActionsTest < Rails::Generators::TestCase
   test "rails command should run rails_command with default env" do
     assert_called_with(generator, :run, ["rails log:clear RAILS_ENV=development", verbose: false]) do
       with_rails_env nil do
-        action :rails_command, 'log:clear'
+        action :rails_command, "log:clear"
       end
     end
   end
 
   test "rails command with env option should run rails_command with same env" do
-    assert_called_with(generator, :run, ['rails log:clear RAILS_ENV=production', verbose: false]) do
-      action :rails_command, 'log:clear', env: 'production'
+    assert_called_with(generator, :run, ["rails log:clear RAILS_ENV=production", verbose: false]) do
+      action :rails_command, "log:clear", env: "production"
     end
   end
 
   test "rails command with RAILS_ENV variable should run rails_command in env" do
-    assert_called_with(generator, :run, ['rails log:clear RAILS_ENV=production', verbose: false]) do
+    assert_called_with(generator, :run, ["rails log:clear RAILS_ENV=production", verbose: false]) do
       with_rails_env "production" do
-        action :rails_command, 'log:clear'
+        action :rails_command, "log:clear"
       end
     end
   end
 
   def test_env_option_should_win_over_rails_env_variable_when_running_rails
-    assert_called_with(generator, :run, ['rails log:clear RAILS_ENV=production', verbose: false]) do
+    assert_called_with(generator, :run, ["rails log:clear RAILS_ENV=production", verbose: false]) do
       with_rails_env "staging" do
-        action :rails_command, 'log:clear', env: 'production'
+        action :rails_command, "log:clear", env: "production"
       end
     end
   end
@@ -272,13 +272,13 @@ class ActionsTest < Rails::Generators::TestCase
   test "rails command with sudo option should run rails_command with sudo" do
     assert_called_with(generator, :run, ["sudo rails log:clear RAILS_ENV=development", verbose: false]) do
       with_rails_env nil do
-        action :rails_command, 'log:clear', sudo: true
+        action :rails_command, "log:clear", sudo: true
       end
     end
   end
 
   def test_capify_should_run_the_capify_command
-    assert_called_with(generator, :run, ['capify .', verbose: false]) do
+    assert_called_with(generator, :run, ["capify .", verbose: false]) do
       action :capify!
     end
   end
@@ -287,12 +287,12 @@ class ActionsTest < Rails::Generators::TestCase
     run_generator
     route_command = "route '/login', controller: 'sessions', action: 'new'"
     action :route, route_command
-    assert_file 'config/routes.rb', /#{Regexp.escape(route_command)}/
+    assert_file "config/routes.rb", /#{Regexp.escape(route_command)}/
   end
 
   def test_route_should_be_idempotent
     run_generator
-    route_path = File.expand_path('config/routes.rb', destination_root)
+    route_path = File.expand_path("config/routes.rb", destination_root)
 
     # runs first time, not asserting
     action :route, "root 'welcome#index'"
@@ -312,8 +312,8 @@ class ActionsTest < Rails::Generators::TestCase
     content = File.read(route_path)
 
     # Remove all of the comments and blank lines from the routes file
-    content.gsub!(/^  \#.*\n/, '')
-    content.gsub!(/^\n/, '')
+    content.gsub!(/^  \#.*\n/, "")
+    content.gsub!(/^\n/, "")
 
     File.open(route_path, "wb") { |file| file.write(content) }
 
diff --git a/railties/test/generators/api_app_generator_test.rb b/railties/test/generators/api_app_generator_test.rb
index 9ad936710d..614ff28da1 100644
--- a/railties/test/generators/api_app_generator_test.rb
+++ b/railties/test/generators/api_app_generator_test.rb
@@ -1,11 +1,11 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/rails/app/app_generator'
+require "generators/generators_test_helper"
+require "rails/generators/rails/app/app_generator"
 
 class ApiAppGeneratorTest < Rails::Generators::TestCase
   include GeneratorsTestHelper
   tests Rails::Generators::AppGenerator
 
-  arguments [destination_root, '--api']
+  arguments [destination_root, "--api"]
 
   def setup
     Rails.application = TestApp::Application
diff --git a/railties/test/generators/app_generator_test.rb b/railties/test/generators/app_generator_test.rb
index 09309b5cd0..54c5115fd9 100644
--- a/railties/test/generators/app_generator_test.rb
+++ b/railties/test/generators/app_generator_test.rb
@@ -1,6 +1,6 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/rails/app/app_generator'
-require 'generators/shared_generator_tests'
+require "generators/generators_test_helper"
+require "rails/generators/rails/app/app_generator"
+require "generators/shared_generator_tests"
 
 DEFAULT_APP_FILES = %w(
   .gitignore
@@ -88,12 +88,12 @@ class AppGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_application_new_exits_with_non_zero_code_on_invalid_application_name
-    quietly { system 'rails new test --no-rc' }
+    quietly { system "rails new test --no-rc" }
     assert_equal false, $?.success?
   end
 
   def test_application_new_exits_with_message_and_non_zero_code_when_generating_inside_existing_rails_directory
-    app_root = File.join(destination_root, 'myfirstapp')
+    app_root = File.join(destination_root, "myfirstapp")
     run_generator [app_root]
     output = nil
     Dir.chdir(app_root) do
@@ -104,7 +104,7 @@ class AppGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_application_new_show_help_message_inside_existing_rails_directory
-    app_root = File.join(destination_root, 'myfirstapp')
+    app_root = File.join(destination_root, "myfirstapp")
     run_generator [app_root]
     output = Dir.chdir(app_root) do
       `rails new --help`
@@ -136,7 +136,7 @@ class AppGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_rails_update_generates_correct_session_key
-    app_root = File.join(destination_root, 'myapp')
+    app_root = File.join(destination_root, "myapp")
     run_generator [app_root]
 
     stub_rails_application(app_root) do
@@ -155,11 +155,11 @@ class AppGeneratorTest < Rails::Generators::TestCase
   def test_new_application_not_include_api_initializers
     run_generator
 
-    assert_no_file 'config/initializers/cors.rb'
+    assert_no_file "config/initializers/cors.rb"
   end
 
   def test_rails_update_keep_the_cookie_serializer_if_it_is_already_configured
-    app_root = File.join(destination_root, 'myapp')
+    app_root = File.join(destination_root, "myapp")
     run_generator [app_root]
 
     stub_rails_application(app_root) do
@@ -171,7 +171,7 @@ class AppGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_rails_update_set_the_cookie_serializer_to_marshal_if_it_is_not_already_configured
-    app_root = File.join(destination_root, 'myapp')
+    app_root = File.join(destination_root, "myapp")
     run_generator [app_root]
 
     FileUtils.rm("#{app_root}/config/initializers/cookies_serializer.rb")
@@ -186,7 +186,7 @@ class AppGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_rails_update_dont_set_file_watcher
-    app_root = File.join(destination_root, 'myapp')
+    app_root = File.join(destination_root, "myapp")
     run_generator [app_root]
 
     stub_rails_application(app_root) do
@@ -200,7 +200,7 @@ class AppGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_rails_update_does_not_create_new_framework_defaults_by_default
-    app_root = File.join(destination_root, 'myapp')
+    app_root = File.join(destination_root, "myapp")
     run_generator [app_root]
 
     FileUtils.rm("#{app_root}/config/initializers/new_framework_defaults.rb")
@@ -219,7 +219,7 @@ class AppGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_rails_update_does_not_create_rack_cors
-    app_root = File.join(destination_root, 'myapp')
+    app_root = File.join(destination_root, "myapp")
     run_generator [app_root]
 
     stub_rails_application(app_root) do
@@ -231,7 +231,7 @@ class AppGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_rails_update_does_not_remove_rack_cors_if_already_present
-    app_root = File.join(destination_root, 'myapp')
+    app_root = File.join(destination_root, "myapp")
     run_generator [app_root]
 
     FileUtils.touch("#{app_root}/config/initializers/cors.rb")
@@ -252,7 +252,7 @@ class AppGeneratorTest < Rails::Generators::TestCase
   def test_gemfile_has_no_whitespace_errors
     run_generator
     absolute = File.expand_path("Gemfile", destination_root)
-    File.open(absolute, 'r') do |f|
+    File.open(absolute, "r") do |f|
       f.each_line do |line|
         assert_no_match %r{/^[ \t]+$/}, line
       end
@@ -385,8 +385,8 @@ class AppGeneratorTest < Rails::Generators::TestCase
   def test_generator_has_assets_gems
     run_generator
 
-    assert_gem 'sass-rails'
-    assert_gem 'uglifier'
+    assert_gem "sass-rails"
+    assert_gem "uglifier"
   end
 
   def test_generator_if_skip_sprockets_is_given
@@ -446,7 +446,7 @@ class AppGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_other_javascript_libraries
-    run_generator [destination_root, '-j', 'prototype']
+    run_generator [destination_root, "-j", "prototype"]
     assert_file "app/assets/javascripts/application.js" do |contents|
       assert_match %r{^//= require prototype}, contents
       assert_match %r{^//= require prototype_ujs}, contents
@@ -478,7 +478,7 @@ class AppGeneratorTest < Rails::Generators::TestCase
 
   def test_inclusion_of_jbuilder
     run_generator
-    assert_gem 'jbuilder'
+    assert_gem "jbuilder"
   end
 
   def test_inclusion_of_a_debugger
@@ -488,13 +488,13 @@ class AppGeneratorTest < Rails::Generators::TestCase
         assert_no_match(/byebug/, content)
       end
     else
-      assert_gem 'byebug'
+      assert_gem "byebug"
     end
   end
 
   def test_inclusion_of_listen_related_configuration_by_default
     run_generator
-    if RbConfig::CONFIG['host_os'] =~ /darwin|linux/
+    if RbConfig::CONFIG["host_os"] =~ /darwin|linux/
       assert_listen_related_configuration
     else
       assert_no_listen_related_configuration
@@ -502,14 +502,14 @@ class AppGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_non_inclusion_of_listen_related_configuration_if_skip_listen
-    run_generator [destination_root, '--skip-listen']
+    run_generator [destination_root, "--skip-listen"]
     assert_no_listen_related_configuration
   end
 
   def test_evented_file_update_checker_config
     run_generator
-    assert_file 'config/environments/development.rb' do |content|
-      if RbConfig::CONFIG['host_os'] =~ /darwin|linux/
+    assert_file "config/environments/development.rb" do |content|
+      if RbConfig::CONFIG["host_os"] =~ /darwin|linux/
         assert_match(/^\s*config.file_watcher = ActiveSupport::EventedFileUpdateChecker/, content)
       else
         assert_match(/^\s*# config.file_watcher = ActiveSupport::EventedFileUpdateChecker/, content)
@@ -539,8 +539,8 @@ class AppGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_file_is_added_for_backwards_compatibility
-    action :file, 'lib/test_file.rb', 'heres test data'
-    assert_file 'lib/test_file.rb', 'heres test data'
+    action :file, "lib/test_file.rb", "heres test data"
+    assert_file "lib/test_file.rb", "heres test data"
   end
 
   def test_tests_are_removed_from_frameworks_if_skip_test_is_given
@@ -564,14 +564,14 @@ class AppGeneratorTest < Rails::Generators::TestCase
     path = File.join(destination_root, "foo bar")
 
     # This also applies to MySQL apps but not with SQLite
-    run_generator [path, "-d", 'postgresql']
+    run_generator [path, "-d", "postgresql"]
 
     assert_file "foo bar/config/database.yml", /database: foo_bar_development/
   end
 
   def test_web_console
     run_generator
-    assert_gem 'web-console'
+    assert_gem "web-console"
   end
 
   def test_web_console_with_dev_option
@@ -598,18 +598,18 @@ class AppGeneratorTest < Rails::Generators::TestCase
 
   def test_dev_option
     assert_generates_with_bundler dev: true
-    rails_path = File.expand_path('../../..', Rails.root)
-    assert_file 'Gemfile', /^gem\s+["']rails["'],\s+path:\s+["']#{Regexp.escape(rails_path)}["']$/
+    rails_path = File.expand_path("../../..", Rails.root)
+    assert_file "Gemfile", /^gem\s+["']rails["'],\s+path:\s+["']#{Regexp.escape(rails_path)}["']$/
   end
 
   def test_edge_option
     assert_generates_with_bundler edge: true
-    assert_file 'Gemfile', %r{^gem\s+["']rails["'],\s+github:\s+["']#{Regexp.escape("rails/rails")}["'],\s+branch:\s+["']#{Regexp.escape("5-0-stable")}["']$}
+    assert_file "Gemfile", %r{^gem\s+["']rails["'],\s+github:\s+["']#{Regexp.escape("rails/rails")}["'],\s+branch:\s+["']#{Regexp.escape("5-0-stable")}["']$}
   end
 
   def test_spring
     run_generator
-    assert_gem 'spring'
+    assert_gem "spring"
   end
 
   def test_spring_binstubs
@@ -618,9 +618,9 @@ class AppGeneratorTest < Rails::Generators::TestCase
       @binstub_called ||= 0
 
       case command
-      when 'install'
+      when "install"
         # Called when running bundle, we just want to stub it so nothing to do here.
-      when 'exec spring binstub --all'
+      when "exec spring binstub --all"
         @binstub_called += 1
         assert_equal 1, @binstub_called, "exec spring binstub --all expected to be called once, but was called #{@install_called} times."
       end
@@ -645,7 +645,7 @@ class AppGeneratorTest < Rails::Generators::TestCase
   def test_skip_spring
     run_generator [destination_root, "--skip-spring"]
 
-    assert_no_file 'config/spring.rb'
+    assert_no_file "config/spring.rb"
     assert_file "Gemfile" do |content|
       assert_no_match(/spring/, content)
     end
@@ -676,15 +676,15 @@ class AppGeneratorTest < Rails::Generators::TestCase
   def test_gitignore_when_sqlite3
     run_generator
 
-    assert_file '.gitignore' do |content|
+    assert_file ".gitignore" do |content|
       assert_match(/sqlite3/, content)
     end
   end
 
   def test_gitignore_when_no_active_record
-    run_generator [destination_root, '--skip-active-record']
+    run_generator [destination_root, "--skip-active-record"]
 
-    assert_file '.gitignore' do |content|
+    assert_file ".gitignore" do |content|
       assert_no_match(/sqlite/i, content)
     end
   end
@@ -692,7 +692,7 @@ class AppGeneratorTest < Rails::Generators::TestCase
   def test_gitignore_when_non_sqlite3_db
     run_generator([destination_root, "-d", "mysql"])
 
-    assert_file '.gitignore' do |content|
+    assert_file ".gitignore" do |content|
       assert_no_match(/sqlite/i, content)
     end
   end
@@ -735,16 +735,16 @@ class AppGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_after_bundle_callback
-    path = 'http://example.org/rails_template'
+    path = "http://example.org/rails_template"
     template = %{ after_bundle { run 'echo ran after_bundle' } }
     template.instance_eval "def read; self; end" # Make the string respond to read
 
     check_open = -> *args do
-      assert_equal [ path, 'Accept' => 'application/x-thor-template' ], args
+      assert_equal [ path, "Accept" => "application/x-thor-template" ], args
       template
     end
 
-    sequence = ['install', 'exec spring binstub --all', 'echo ran after_bundle']
+    sequence = ["install", "exec spring binstub --all", "echo ran after_bundle"]
       @sequence_step ||= 0
     ensure_bundler_first = -> command do
       assert_equal sequence[@sequence_step], command, "commands should be called in sequence #{sequence}"
@@ -784,20 +784,20 @@ class AppGeneratorTest < Rails::Generators::TestCase
     end
 
     def assert_listen_related_configuration
-      assert_gem 'listen'
-      assert_gem 'spring-watcher-listen'
+      assert_gem "listen"
+      assert_gem "spring-watcher-listen"
 
-      assert_file 'config/environments/development.rb' do |content|
+      assert_file "config/environments/development.rb" do |content|
         assert_match(/^\s*config.file_watcher = ActiveSupport::EventedFileUpdateChecker/, content)
       end
     end
 
     def assert_no_listen_related_configuration
-      assert_file 'Gemfile' do |content|
+      assert_file "Gemfile" do |content|
         assert_no_match(/listen/, content)
       end
 
-      assert_file 'config/environments/development.rb' do |content|
+      assert_file "config/environments/development.rb" do |content|
         assert_match(/^\s*# config.file_watcher = ActiveSupport::EventedFileUpdateChecker/, content)
       end
     end
@@ -809,10 +809,10 @@ class AppGeneratorTest < Rails::Generators::TestCase
         @install_called ||= 0
 
         case command
-        when 'install'
+        when "install"
           @install_called += 1
           assert_equal 1, @install_called, "install expected to be called once, but was called #{@install_called} times"
-        when 'exec spring binstub --all'
+        when "exec spring binstub --all"
           # Called when running tests with spring, let through unscathed.
         end
       end
diff --git a/railties/test/generators/argv_scrubber_test.rb b/railties/test/generators/argv_scrubber_test.rb
index 31e07bc8da..7f4295a20f 100644
--- a/railties/test/generators/argv_scrubber_test.rb
+++ b/railties/test/generators/argv_scrubber_test.rb
@@ -1,7 +1,7 @@
-require 'active_support/test_case'
-require 'active_support/testing/autorun'
-require 'rails/generators/rails/app/app_generator'
-require 'tempfile'
+require "active_support/test_case"
+require "active_support/testing/autorun"
+require "rails/generators/rails/app/app_generator"
+require "tempfile"
 
 module Rails
   module Generators
@@ -11,7 +11,7 @@ module Rails
       # *must* act this way, I just want to prevent regressions.
 
       def test_version
-        ['-v', '--version'].each do |str|
+        ["-v", "--version"].each do |str|
           scrubber = ARGVScrubber.new [str]
           output    = nil
           exit_code = nil
@@ -26,37 +26,37 @@ module Rails
       end
 
       def test_default_help
-        argv = ['zomg', 'how', 'are', 'you']
+        argv = ["zomg", "how", "are", "you"]
         scrubber = ARGVScrubber.new argv
         args = scrubber.prepare!
-        assert_equal ['--help'] + argv.drop(1), args
+        assert_equal ["--help"] + argv.drop(1), args
       end
 
       def test_prepare_returns_args
-        scrubber = ARGVScrubber.new ['hi mom']
+        scrubber = ARGVScrubber.new ["hi mom"]
         args = scrubber.prepare!
-        assert_equal '--help', args.first
+        assert_equal "--help", args.first
       end
 
       def test_no_mutations
-        scrubber = ARGVScrubber.new ['hi mom'].freeze
+        scrubber = ARGVScrubber.new ["hi mom"].freeze
         args = scrubber.prepare!
-        assert_equal '--help', args.first
+        assert_equal "--help", args.first
       end
 
       def test_new_command_no_rc
         scrubber = Class.new(ARGVScrubber) {
           def self.default_rc_file
-            File.join(Dir.tmpdir, 'whatever')
+            File.join(Dir.tmpdir, "whatever")
           end
-        }.new ['new']
+        }.new ["new"]
         args = scrubber.prepare!
         assert_equal [], args
       end
 
       def test_new_homedir_rc
-        file = Tempfile.new 'myrcfile'
-        file.puts '--hello-world'
+        file = Tempfile.new "myrcfile"
+        file.puts "--hello-world"
         file.flush
 
         message = nil
@@ -65,10 +65,10 @@ module Rails
             file.path
           end
           define_method(:puts) { |msg| message = msg }
-        }.new ['new']
+        }.new ["new"]
         args = scrubber.prepare!
-        assert_equal ['--hello-world'], args
-        assert_match 'hello-world', message
+        assert_equal ["--hello-world"], args
+        assert_match "hello-world", message
         assert_match file.path, message
       ensure
         file.close
@@ -76,33 +76,33 @@ module Rails
       end
 
       def test_rc_whitespace_separated
-        file = Tempfile.new 'myrcfile'
-        file.puts '--hello --world'
+        file = Tempfile.new "myrcfile"
+        file.puts "--hello --world"
         file.flush
 
         message = nil
         scrubber = Class.new(ARGVScrubber) {
           define_method(:puts) { |msg| message = msg }
-        }.new ['new', "--rc=#{file.path}"]
+        }.new ["new", "--rc=#{file.path}"]
         args = scrubber.prepare!
-        assert_equal ['--hello', '--world'], args
+        assert_equal ["--hello", "--world"], args
       ensure
         file.close
         file.unlink
       end
 
       def test_new_rc_option
-        file = Tempfile.new 'myrcfile'
-        file.puts '--hello-world'
+        file = Tempfile.new "myrcfile"
+        file.puts "--hello-world"
         file.flush
 
         message = nil
         scrubber = Class.new(ARGVScrubber) {
           define_method(:puts) { |msg| message = msg }
-        }.new ['new', "--rc=#{file.path}"]
+        }.new ["new", "--rc=#{file.path}"]
         args = scrubber.prepare!
-        assert_equal ['--hello-world'], args
-        assert_match 'hello-world', message
+        assert_equal ["--hello-world"], args
+        assert_match "hello-world", message
         assert_match file.path, message
       ensure
         file.close
@@ -110,14 +110,14 @@ module Rails
       end
 
       def test_new_rc_option_and_custom_options
-        file = Tempfile.new 'myrcfile'
-        file.puts '--hello'
-        file.puts '--world'
+        file = Tempfile.new "myrcfile"
+        file.puts "--hello"
+        file.puts "--world"
         file.flush
 
         scrubber = Class.new(ARGVScrubber) {
           define_method(:puts) { |msg| }
-        }.new ['new', 'tenderapp', '--love', "--rc=#{file.path}"]
+        }.new ["new", "tenderapp", "--love", "--rc=#{file.path}"]
 
         args = scrubber.prepare!
         assert_equal ["tenderapp", "--hello", "--world", "--love"], args
@@ -127,7 +127,7 @@ module Rails
       end
 
       def test_no_rc
-        scrubber = ARGVScrubber.new ['new', '--no-rc']
+        scrubber = ARGVScrubber.new ["new", "--no-rc"]
         args = scrubber.prepare!
         assert_equal [], args
       end
diff --git a/railties/test/generators/assets_generator_test.rb b/railties/test/generators/assets_generator_test.rb
index a2b94f2e50..1c02c67e42 100644
--- a/railties/test/generators/assets_generator_test.rb
+++ b/railties/test/generators/assets_generator_test.rb
@@ -1,5 +1,5 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/rails/assets/assets_generator'
+require "generators/generators_test_helper"
+require "rails/generators/rails/assets/assets_generator"
 
 class AssetsGeneratorTest < Rails::Generators::TestCase
   include GeneratorsTestHelper
diff --git a/railties/test/generators/channel_generator_test.rb b/railties/test/generators/channel_generator_test.rb
index e3edde681f..a1d54200ba 100644
--- a/railties/test/generators/channel_generator_test.rb
+++ b/railties/test/generators/channel_generator_test.rb
@@ -1,12 +1,12 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/channel/channel_generator'
+require "generators/generators_test_helper"
+require "rails/generators/channel/channel_generator"
 
 class ChannelGeneratorTest < Rails::Generators::TestCase
   include GeneratorsTestHelper
   tests Rails::Generators::ChannelGenerator
 
   def test_application_cable_skeleton_is_created
-    run_generator ['books']
+    run_generator ["books"]
 
     assert_file "app/channels/application_cable/channel.rb" do |cable|
       assert_match(/module ApplicationCable\n  class Channel < ActionCable::Channel::Base\n/, cable)
@@ -18,7 +18,7 @@ class ChannelGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_channel_is_created
-    run_generator ['chat']
+    run_generator ["chat"]
 
     assert_file "app/channels/chat_channel.rb" do |channel|
       assert_match(/class ChatChannel < ApplicationCable::Channel/, channel)
@@ -30,7 +30,7 @@ class ChannelGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_channel_with_multiple_actions_is_created
-    run_generator ['chat', 'speak', 'mute']
+    run_generator ["chat", "speak", "mute"]
 
     assert_file "app/channels/chat_channel.rb" do |channel|
       assert_match(/class ChatChannel < ApplicationCable::Channel/, channel)
@@ -46,7 +46,7 @@ class ChannelGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_channel_asset_is_not_created_when_skip_assets_is_passed
-    run_generator ['chat', '--skip-assets']
+    run_generator ["chat", "--skip-assets"]
 
     assert_file "app/channels/chat_channel.rb" do |channel|
       assert_match(/class ChatChannel < ApplicationCable::Channel/, channel)
@@ -56,16 +56,16 @@ class ChannelGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_cable_js_is_created_if_not_present_already
-    run_generator ['chat']
+    run_generator ["chat"]
     FileUtils.rm("#{destination_root}/app/assets/javascripts/cable.js")
-    run_generator ['camp']
+    run_generator ["camp"]
 
     assert_file "app/assets/javascripts/cable.js"
   end
 
   def test_channel_on_revoke
-    run_generator ['chat']
-    run_generator ['chat'], behavior: :revoke
+    run_generator ["chat"]
+    run_generator ["chat"], behavior: :revoke
 
     assert_no_file "app/channels/chat_channel.rb"
     assert_no_file "app/assets/javascripts/channels/chat.js"
diff --git a/railties/test/generators/controller_generator_test.rb b/railties/test/generators/controller_generator_test.rb
index 1351151afb..dd19c5e166 100644
--- a/railties/test/generators/controller_generator_test.rb
+++ b/railties/test/generators/controller_generator_test.rb
@@ -1,5 +1,5 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/rails/controller/controller_generator'
+require "generators/generators_test_helper"
+require "rails/generators/rails/controller/controller_generator"
 
 class ControllerGeneratorTest < Rails::Generators::TestCase
   include GeneratorsTestHelper
diff --git a/railties/test/generators/create_migration_test.rb b/railties/test/generators/create_migration_test.rb
index e16a77479a..661a26afad 100644
--- a/railties/test/generators/create_migration_test.rb
+++ b/railties/test/generators/create_migration_test.rb
@@ -1,5 +1,5 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/rails/migration/migration_generator'
+require "generators/generators_test_helper"
+require "rails/generators/rails/migration/migration_generator"
 
 class CreateMigrationTest < Rails::Generators::TestCase
   include GeneratorsTestHelper
@@ -19,12 +19,12 @@ class CreateMigrationTest < Rails::Generators::TestCase
   end
 
   def create_migration(destination_path = default_destination_path, config = {}, generator_options = {}, &block)
-    migration_name = File.basename(destination_path, '.rb')
+    migration_name = File.basename(destination_path, ".rb")
     generator([migration_name], generator_options)
     generator.set_migration_assigns!(destination_path)
 
     dir, base = File.split(destination_path)
-    timestamped_destination_path = File.join(dir, ["%migration_number%", base].join('_'))
+    timestamped_destination_path = File.join(dir, ["%migration_number%", base].join("_"))
 
     @migration = Rails::Generators::Actions::CreateMigration.new(generator, timestamped_destination_path, block || "contents", config)
   end
diff --git a/railties/test/generators/generated_attribute_test.rb b/railties/test/generators/generated_attribute_test.rb
index ee7c009305..97847c8624 100644
--- a/railties/test/generators/generated_attribute_test.rb
+++ b/railties/test/generators/generated_attribute_test.rb
@@ -1,5 +1,5 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/generated_attribute'
+require "generators/generators_test_helper"
+require "rails/generators/generated_attribute"
 
 class GeneratedAttributeTest < Rails::Generators::TestCase
   include GeneratorsTestHelper
@@ -51,7 +51,7 @@ class GeneratedAttributeTest < Rails::Generators::TestCase
   end
 
   def test_default_value_is_decimal
-    assert_field_default_value :decimal, '9.99'
+    assert_field_default_value :decimal, "9.99"
   end
 
   def test_default_value_is_datetime
@@ -65,7 +65,7 @@ class GeneratedAttributeTest < Rails::Generators::TestCase
   end
 
   def test_default_value_is_string
-    assert_field_default_value :string, 'MyString'
+    assert_field_default_value :string, "MyString"
   end
 
   def test_default_value_for_type
@@ -74,7 +74,7 @@ class GeneratedAttributeTest < Rails::Generators::TestCase
   end
 
   def test_default_value_is_text
-    assert_field_default_value :text, 'MyText'
+    assert_field_default_value :text, "MyText"
   end
 
   def test_default_value_is_boolean
@@ -89,14 +89,14 @@ class GeneratedAttributeTest < Rails::Generators::TestCase
 
   def test_default_value_is_empty_string
     %w(foo bar baz).each do |attribute_type|
-      assert_field_default_value attribute_type, ''
+      assert_field_default_value attribute_type, ""
     end
   end
 
   def test_human_name
     assert_equal(
-      'Full name',
-      create_generated_attribute(:string, 'full_name').human_name
+      "Full name",
+      create_generated_attribute(:string, "full_name").human_name
     )
   end
 
@@ -125,21 +125,21 @@ class GeneratedAttributeTest < Rails::Generators::TestCase
   end
 
   def test_blank_type_defaults_to_string_raises_exception
-    assert_equal :string, create_generated_attribute(nil, 'title').type
-    assert_equal :string, create_generated_attribute("", 'title').type
+    assert_equal :string, create_generated_attribute(nil, "title").type
+    assert_equal :string, create_generated_attribute("", "title").type
   end
 
   def test_handles_index_names_for_references
-    assert_equal "post", create_generated_attribute('string', 'post').index_name
-    assert_equal "post_id", create_generated_attribute('references', 'post').index_name
-    assert_equal "post_id", create_generated_attribute('belongs_to', 'post').index_name
-    assert_equal ["post_id", "post_type"], create_generated_attribute('references{polymorphic}', 'post').index_name
+    assert_equal "post", create_generated_attribute("string", "post").index_name
+    assert_equal "post_id", create_generated_attribute("references", "post").index_name
+    assert_equal "post_id", create_generated_attribute("belongs_to", "post").index_name
+    assert_equal ["post_id", "post_type"], create_generated_attribute("references{polymorphic}", "post").index_name
   end
 
   def test_handles_column_names_for_references
-    assert_equal "post", create_generated_attribute('string', 'post').column_name
-    assert_equal "post_id", create_generated_attribute('references', 'post').column_name
-    assert_equal "post_id", create_generated_attribute('belongs_to', 'post').column_name
+    assert_equal "post", create_generated_attribute("string", "post").column_name
+    assert_equal "post_id", create_generated_attribute("references", "post").column_name
+    assert_equal "post_id", create_generated_attribute("belongs_to", "post").column_name
   end
 
   def test_parse_required_attribute_with_index
diff --git a/railties/test/generators/generator_generator_test.rb b/railties/test/generators/generator_generator_test.rb
index dcfeaaa8e0..d68cdc29b0 100644
--- a/railties/test/generators/generator_generator_test.rb
+++ b/railties/test/generators/generator_generator_test.rb
@@ -1,5 +1,5 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/rails/generator/generator_generator'
+require "generators/generators_test_helper"
+require "rails/generators/rails/generator/generator_generator"
 
 class GeneratorGeneratorTest < Rails::Generators::TestCase
   include GeneratorsTestHelper
diff --git a/railties/test/generators/generator_test.rb b/railties/test/generators/generator_test.rb
index 8ef44a8dcb..c4e4747468 100644
--- a/railties/test/generators/generator_test.rb
+++ b/railties/test/generators/generator_test.rb
@@ -1,6 +1,6 @@
-require 'active_support/test_case'
-require 'active_support/testing/autorun'
-require 'rails/generators/app_base'
+require "active_support/test_case"
+require "active_support/testing/autorun"
+require "rails/generators/app_base"
 
 module Rails
   module Generators
@@ -21,46 +21,46 @@ module Rails
 
       def test_construction
         klass     = make_builder_class
-        assert klass.start(['new', 'blah'])
+        assert klass.start(["new", "blah"])
       end
 
       def test_add_gem
         klass = make_builder_class
-        generator = klass.start(['new', 'blah'])
-        generator.gemfile_entry 'tenderlove'
-        assert_includes generator.gemfile_entries.map(&:name), 'tenderlove'
+        generator = klass.start(["new", "blah"])
+        generator.gemfile_entry "tenderlove"
+        assert_includes generator.gemfile_entries.map(&:name), "tenderlove"
       end
 
       def test_add_gem_with_version
         klass = make_builder_class
-        generator = klass.start(['new', 'blah'])
-        generator.gemfile_entry 'tenderlove', '2.0.0'
+        generator = klass.start(["new", "blah"])
+        generator.gemfile_entry "tenderlove", "2.0.0"
         assert generator.gemfile_entries.find { |gfe|
-          gfe.name == 'tenderlove' && gfe.version == '2.0.0'
+          gfe.name == "tenderlove" && gfe.version == "2.0.0"
         }
       end
 
       def test_add_github_gem
         klass = make_builder_class
-        generator = klass.start(['new', 'blah'])
-        generator.gemfile_entry 'tenderlove', github: 'hello world'
+        generator = klass.start(["new", "blah"])
+        generator.gemfile_entry "tenderlove", github: "hello world"
         assert generator.gemfile_entries.find { |gfe|
-          gfe.name == 'tenderlove' && gfe.options[:github] == 'hello world'
+          gfe.name == "tenderlove" && gfe.options[:github] == "hello world"
         }
       end
 
       def test_add_path_gem
         klass = make_builder_class
-        generator = klass.start(['new', 'blah'])
-        generator.gemfile_entry 'tenderlove', path: 'hello world'
+        generator = klass.start(["new", "blah"])
+        generator.gemfile_entry "tenderlove", path: "hello world"
         assert generator.gemfile_entries.find { |gfe|
-          gfe.name == 'tenderlove' && gfe.options[:path] == 'hello world'
+          gfe.name == "tenderlove" && gfe.options[:path] == "hello world"
         }
       end
 
       def test_filter
         klass     = make_builder_class
-        generator = klass.start(['new', 'blah'])
+        generator = klass.start(["new", "blah"])
         gems      = generator.gemfile_entries
         generator.add_gem_entry_filter { |gem|
           gem.name != gems.first.name
@@ -70,7 +70,7 @@ module Rails
 
       def test_two_filters
         klass     = make_builder_class
-        generator = klass.start(['new', 'blah'])
+        generator = klass.start(["new", "blah"])
         gems      = generator.gemfile_entries
         generator.add_gem_entry_filter { |gem|
           gem.name != gems.first.name
@@ -83,17 +83,17 @@ module Rails
 
       def test_recommended_rails_versions
         klass     = make_builder_class
-        generator = klass.start(['new', 'blah'])
+        generator = klass.start(["new", "blah"])
 
         specifier_for = -> v { generator.send(:rails_version_specifier, Gem::Version.new(v)) }
 
-        assert_equal '~> 4.1.13', specifier_for['4.1.13']
-        assert_equal ['>= 4.1.6.rc1', '< 4.2'], specifier_for['4.1.6.rc1']
-        assert_equal ['~> 4.1.7', '>= 4.1.7.1'], specifier_for['4.1.7.1']
-        assert_equal ['~> 4.1.7', '>= 4.1.7.1.2'], specifier_for['4.1.7.1.2']
-        assert_equal ['>= 4.1.7.1.rc2', '< 4.2'], specifier_for['4.1.7.1.rc2']
-        assert_equal ['>= 4.2.0.beta1', '< 4.3'], specifier_for['4.2.0.beta1']
-        assert_equal ['>= 5.0.0.beta1', '< 5.1'], specifier_for['5.0.0.beta1']
+        assert_equal "~> 4.1.13", specifier_for["4.1.13"]
+        assert_equal [">= 4.1.6.rc1", "< 4.2"], specifier_for["4.1.6.rc1"]
+        assert_equal ["~> 4.1.7", ">= 4.1.7.1"], specifier_for["4.1.7.1"]
+        assert_equal ["~> 4.1.7", ">= 4.1.7.1.2"], specifier_for["4.1.7.1.2"]
+        assert_equal [">= 4.1.7.1.rc2", "< 4.2"], specifier_for["4.1.7.1.rc2"]
+        assert_equal [">= 4.2.0.beta1", "< 4.3"], specifier_for["4.2.0.beta1"]
+        assert_equal [">= 5.0.0.beta1", "< 5.1"], specifier_for["5.0.0.beta1"]
       end
     end
   end
diff --git a/railties/test/generators/generators_test_helper.rb b/railties/test/generators/generators_test_helper.rb
index b19a5a7144..47e8ac5e61 100644
--- a/railties/test/generators/generators_test_helper.rb
+++ b/railties/test/generators/generators_test_helper.rb
@@ -1,15 +1,15 @@
-require 'abstract_unit'
-require 'active_support/core_ext/module/remove_method'
-require 'active_support/testing/stream'
-require 'active_support/testing/method_call_assertions'
-require 'rails/generators'
-require 'rails/generators/test_case'
+require "abstract_unit"
+require "active_support/core_ext/module/remove_method"
+require "active_support/testing/stream"
+require "active_support/testing/method_call_assertions"
+require "rails/generators"
+require "rails/generators/test_case"
 
 module Rails
   class << self
     remove_possible_method :root
     def root
-      @root ||= Pathname.new(File.expand_path('../../fixtures', __FILE__))
+      @root ||= Pathname.new(File.expand_path("../../fixtures", __FILE__))
     end
   end
 end
@@ -20,9 +20,9 @@ Rails.application.config.generators.templates = [File.join(Rails.root, "lib", "t
 # Rails.application.config.generators to Rails::Generators
 Rails.application.load_generators
 
-require 'active_record'
-require 'action_dispatch'
-require 'action_view'
+require "active_record"
+require "action_dispatch"
+require "action_view"
 
 module GeneratorsTestHelper
   include ActiveSupport::Testing::Stream
@@ -34,7 +34,7 @@ module GeneratorsTestHelper
       setup :prepare_destination
 
       begin
-        base.tests Rails::Generators.const_get(base.name.sub(/Test$/, ''))
+        base.tests Rails::Generators.const_get(base.name.sub(/Test$/, ""))
       rescue
       end
     end
diff --git a/railties/test/generators/helper_generator_test.rb b/railties/test/generators/helper_generator_test.rb
index add04f21a4..e64cb4cbe0 100644
--- a/railties/test/generators/helper_generator_test.rb
+++ b/railties/test/generators/helper_generator_test.rb
@@ -1,5 +1,5 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/rails/helper/helper_generator'
+require "generators/generators_test_helper"
+require "rails/generators/rails/helper/helper_generator"
 
 ObjectHelper = Class.new
 AnotherObjectHelperTest = Class.new
diff --git a/railties/test/generators/integration_test_generator_test.rb b/railties/test/generators/integration_test_generator_test.rb
index d05ed76d24..8bcc02440a 100644
--- a/railties/test/generators/integration_test_generator_test.rb
+++ b/railties/test/generators/integration_test_generator_test.rb
@@ -1,5 +1,5 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/rails/integration_test/integration_test_generator'
+require "generators/generators_test_helper"
+require "rails/generators/rails/integration_test/integration_test_generator"
 
 class IntegrationTestGeneratorTest < Rails::Generators::TestCase
   include GeneratorsTestHelper
diff --git a/railties/test/generators/job_generator_test.rb b/railties/test/generators/job_generator_test.rb
index dbff0ab704..68d158eb39 100644
--- a/railties/test/generators/job_generator_test.rb
+++ b/railties/test/generators/job_generator_test.rb
@@ -1,5 +1,5 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/job/job_generator'
+require "generators/generators_test_helper"
+require "rails/generators/job/job_generator"
 
 class JobGeneratorTest < Rails::Generators::TestCase
   include GeneratorsTestHelper
diff --git a/railties/test/generators/mailer_generator_test.rb b/railties/test/generators/mailer_generator_test.rb
index 6a4951840d..1edaa1b37f 100644
--- a/railties/test/generators/mailer_generator_test.rb
+++ b/railties/test/generators/mailer_generator_test.rb
@@ -1,5 +1,5 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/mailer/mailer_generator'
+require "generators/generators_test_helper"
+require "rails/generators/mailer/mailer_generator"
 
 class MailerGeneratorTest < Rails::Generators::TestCase
   include GeneratorsTestHelper
@@ -13,7 +13,7 @@ class MailerGeneratorTest < Rails::Generators::TestCase
       assert_no_match(/layout :mailer_notifier/, mailer)
     end
 
-    assert_file 'app/mailers/application_mailer.rb' do |mailer|
+    assert_file "app/mailers/application_mailer.rb" do |mailer|
       assert_match(/class ApplicationMailer < ActionMailer::Base/, mailer)
       assert_match(/default from: 'from@example.com'/, mailer)
       assert_match(/layout 'mailer'/, mailer)
diff --git a/railties/test/generators/migration_generator_test.rb b/railties/test/generators/migration_generator_test.rb
index 46154b7db2..6e1d1b70a9 100644
--- a/railties/test/generators/migration_generator_test.rb
+++ b/railties/test/generators/migration_generator_test.rb
@@ -1,5 +1,5 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/rails/migration/migration_generator'
+require "generators/generators_test_helper"
+require "rails/generators/rails/migration/migration_generator"
 
 class MigrationGeneratorTest < Rails::Generators::TestCase
   include GeneratorsTestHelper
@@ -17,7 +17,7 @@ class MigrationGeneratorTest < Rails::Generators::TestCase
       run_generator [migration]
       file_name = migration_file_name "db/migrate/#{migration}.rb"
 
-      File.basename(file_name).split('_').first
+      File.basename(file_name).split("_").first
     end
 
     assert_not_equal first_migration_number, second_migration_number
@@ -248,7 +248,7 @@ class MigrationGeneratorTest < Rails::Generators::TestCase
   def test_migration_with_singular_table_name
     with_singular_table_name do
       migration = "add_title_body_to_post"
-      run_generator [migration, 'title:string']
+      run_generator [migration, "title:string"]
       assert_migration "db/migrate/#{migration}.rb" do |content|
         assert_method :change, content do |change|
           assert_match(/add_column :post, :title, :string/, change)
diff --git a/railties/test/generators/model_generator_test.rb b/railties/test/generators/model_generator_test.rb
index 6b30c40476..45760d7129 100644
--- a/railties/test/generators/model_generator_test.rb
+++ b/railties/test/generators/model_generator_test.rb
@@ -1,6 +1,6 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/rails/model/model_generator'
-require 'active_support/core_ext/string/strip'
+require "generators/generators_test_helper"
+require "rails/generators/rails/model/model_generator"
+require "active_support/core_ext/string/strip"
 
 class ModelGeneratorTest < Rails::Generators::TestCase
   include GeneratorsTestHelper
diff --git a/railties/test/generators/named_base_test.rb b/railties/test/generators/named_base_test.rb
index 291f5e06c3..c58468dfc1 100644
--- a/railties/test/generators/named_base_test.rb
+++ b/railties/test/generators/named_base_test.rb
@@ -1,84 +1,84 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/rails/scaffold_controller/scaffold_controller_generator'
+require "generators/generators_test_helper"
+require "rails/generators/rails/scaffold_controller/scaffold_controller_generator"
 
 class NamedBaseTest < Rails::Generators::TestCase
   include GeneratorsTestHelper
   tests Rails::Generators::ScaffoldControllerGenerator
 
   def test_named_generator_with_underscore
-    g = generator ['line_item']
-    assert_name g, 'line_item',  :name
+    g = generator ["line_item"]
+    assert_name g, "line_item",  :name
     assert_name g, %w(),         :class_path
-    assert_name g, 'LineItem',   :class_name
-    assert_name g, 'line_item',  :file_path
-    assert_name g, 'line_item',  :file_name
-    assert_name g, 'Line item',  :human_name
-    assert_name g, 'line_item',  :singular_name
-    assert_name g, 'line_items', :plural_name
-    assert_name g, 'line_item',  :i18n_scope
-    assert_name g, 'line_items', :table_name
+    assert_name g, "LineItem",   :class_name
+    assert_name g, "line_item",  :file_path
+    assert_name g, "line_item",  :file_name
+    assert_name g, "Line item",  :human_name
+    assert_name g, "line_item",  :singular_name
+    assert_name g, "line_items", :plural_name
+    assert_name g, "line_item",  :i18n_scope
+    assert_name g, "line_items", :table_name
   end
 
   def test_named_generator_attributes
-    g = generator ['admin/foo']
-    assert_name g, 'admin/foo',  :name
+    g = generator ["admin/foo"]
+    assert_name g, "admin/foo",  :name
     assert_name g, %w(admin),    :class_path
-    assert_name g, 'Admin::Foo', :class_name
-    assert_name g, 'admin/foo',  :file_path
-    assert_name g, 'foo',        :file_name
-    assert_name g, 'Foo',        :human_name
-    assert_name g, 'foo',        :singular_name
-    assert_name g, 'foos',       :plural_name
-    assert_name g, 'admin.foo',  :i18n_scope
-    assert_name g, 'admin_foos', :table_name
+    assert_name g, "Admin::Foo", :class_name
+    assert_name g, "admin/foo",  :file_path
+    assert_name g, "foo",        :file_name
+    assert_name g, "Foo",        :human_name
+    assert_name g, "foo",        :singular_name
+    assert_name g, "foos",       :plural_name
+    assert_name g, "admin.foo",  :i18n_scope
+    assert_name g, "admin_foos", :table_name
   end
 
   def test_named_generator_attributes_as_ruby
-    g = generator ['Admin::Foo']
-    assert_name g, 'Admin::Foo', :name
+    g = generator ["Admin::Foo"]
+    assert_name g, "Admin::Foo", :name
     assert_name g, %w(admin),    :class_path
-    assert_name g, 'Admin::Foo', :class_name
-    assert_name g, 'admin/foo',  :file_path
-    assert_name g, 'foo',        :file_name
-    assert_name g, 'foo',        :singular_name
-    assert_name g, 'Foo',        :human_name
-    assert_name g, 'foos',       :plural_name
-    assert_name g, 'admin.foo',  :i18n_scope
-    assert_name g, 'admin_foos', :table_name
+    assert_name g, "Admin::Foo", :class_name
+    assert_name g, "admin/foo",  :file_path
+    assert_name g, "foo",        :file_name
+    assert_name g, "foo",        :singular_name
+    assert_name g, "Foo",        :human_name
+    assert_name g, "foos",       :plural_name
+    assert_name g, "admin.foo",  :i18n_scope
+    assert_name g, "admin_foos", :table_name
   end
 
   def test_named_generator_attributes_without_pluralized
     original_pluralize_table_names = ActiveRecord::Base.pluralize_table_names
     ActiveRecord::Base.pluralize_table_names = false
 
-    g = generator ['admin/foo']
-    assert_name g, 'admin_foo', :table_name
+    g = generator ["admin/foo"]
+    assert_name g, "admin_foo", :table_name
   ensure
     ActiveRecord::Base.pluralize_table_names = original_pluralize_table_names
   end
 
   def test_scaffold_plural_names
-    g = generator ['admin/foo']
-    assert_name g, 'admin/foos',  :controller_name
+    g = generator ["admin/foo"]
+    assert_name g, "admin/foos",  :controller_name
     assert_name g, %w(admin),     :controller_class_path
-    assert_name g, 'Admin::Foos', :controller_class_name
-    assert_name g, 'admin/foos',  :controller_file_path
-    assert_name g, 'foos',        :controller_file_name
-    assert_name g, 'admin.foos',  :controller_i18n_scope
+    assert_name g, "Admin::Foos", :controller_class_name
+    assert_name g, "admin/foos",  :controller_file_path
+    assert_name g, "foos",        :controller_file_name
+    assert_name g, "admin.foos",  :controller_i18n_scope
   end
 
   def test_scaffold_plural_names_as_ruby
-    g = generator ['Admin::Foo']
-    assert_name g, 'Admin::Foos', :controller_name
+    g = generator ["Admin::Foo"]
+    assert_name g, "Admin::Foos", :controller_name
     assert_name g, %w(admin),     :controller_class_path
-    assert_name g, 'Admin::Foos', :controller_class_name
-    assert_name g, 'admin/foos',  :controller_file_path
-    assert_name g, 'foos',        :controller_file_name
-    assert_name g, 'admin.foos',  :controller_i18n_scope
+    assert_name g, "Admin::Foos", :controller_class_name
+    assert_name g, "admin/foos",  :controller_file_path
+    assert_name g, "foos",        :controller_file_name
+    assert_name g, "admin.foos",  :controller_i18n_scope
   end
 
   def test_application_name
-    g = generator ['Admin::Foo']
+    g = generator ["Admin::Foo"]
     Rails.stub(:application, Object.new) do
       assert_name g, "object", :application_name
     end
@@ -89,46 +89,46 @@ class NamedBaseTest < Rails::Generators::TestCase
   end
 
   def test_index_helper
-    g = generator ['Post']
-    assert_name g, 'posts', :index_helper
+    g = generator ["Post"]
+    assert_name g, "posts", :index_helper
   end
 
   def test_index_helper_to_pluralize_once
-    g = generator ['Stadium']
-    assert_name g, 'stadia', :index_helper
+    g = generator ["Stadium"]
+    assert_name g, "stadia", :index_helper
   end
 
   def test_index_helper_with_uncountable
-    g = generator ['Sheep']
-    assert_name g, 'sheep_index', :index_helper
+    g = generator ["Sheep"]
+    assert_name g, "sheep_index", :index_helper
   end
 
   def test_hide_namespace
-    g = generator ['Hidden']
-    g.class.stub(:namespace, 'hidden') do
-      assert !Rails::Generators.hidden_namespaces.include?('hidden')
+    g = generator ["Hidden"]
+    g.class.stub(:namespace, "hidden") do
+      assert !Rails::Generators.hidden_namespaces.include?("hidden")
       g.class.hide!
-      assert Rails::Generators.hidden_namespaces.include?('hidden')
+      assert Rails::Generators.hidden_namespaces.include?("hidden")
     end
   end
 
   def test_scaffold_plural_names_with_model_name_option
-    g = generator ['Admin::Foo'], model_name: 'User'
-    assert_name g, 'user',        :singular_name
-    assert_name g, 'User',        :name
-    assert_name g, 'user',        :file_path
-    assert_name g, 'User',        :class_name
-    assert_name g, 'user',        :file_name
-    assert_name g, 'User',        :human_name
-    assert_name g, 'users',       :plural_name
-    assert_name g, 'user',        :i18n_scope
-    assert_name g, 'users',       :table_name
-    assert_name g, 'Admin::Foos', :controller_name
+    g = generator ["Admin::Foo"], model_name: "User"
+    assert_name g, "user",        :singular_name
+    assert_name g, "User",        :name
+    assert_name g, "user",        :file_path
+    assert_name g, "User",        :class_name
+    assert_name g, "user",        :file_name
+    assert_name g, "User",        :human_name
+    assert_name g, "users",       :plural_name
+    assert_name g, "user",        :i18n_scope
+    assert_name g, "users",       :table_name
+    assert_name g, "Admin::Foos", :controller_name
     assert_name g, %w(admin),     :controller_class_path
-    assert_name g, 'Admin::Foos', :controller_class_name
-    assert_name g, 'admin/foos',  :controller_file_path
-    assert_name g, 'foos',        :controller_file_name
-    assert_name g, 'admin.foos',  :controller_i18n_scope
+    assert_name g, "Admin::Foos", :controller_class_name
+    assert_name g, "admin/foos",  :controller_file_path
+    assert_name g, "foos",        :controller_file_name
+    assert_name g, "admin.foos",  :controller_i18n_scope
   end
 
   protected
diff --git a/railties/test/generators/namespaced_generators_test.rb b/railties/test/generators/namespaced_generators_test.rb
index 902c340321..1caabbe6b1 100644
--- a/railties/test/generators/namespaced_generators_test.rb
+++ b/railties/test/generators/namespaced_generators_test.rb
@@ -1,8 +1,8 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/rails/controller/controller_generator'
-require 'rails/generators/rails/model/model_generator'
-require 'rails/generators/mailer/mailer_generator'
-require 'rails/generators/rails/scaffold/scaffold_generator'
+require "generators/generators_test_helper"
+require "rails/generators/rails/controller/controller_generator"
+require "rails/generators/rails/model/model_generator"
+require "rails/generators/mailer/mailer_generator"
+require "rails/generators/rails/scaffold/scaffold_generator"
 
 class NamespacedGeneratorTestCase < Rails::Generators::TestCase
   include GeneratorsTestHelper
diff --git a/railties/test/generators/plugin_generator_test.rb b/railties/test/generators/plugin_generator_test.rb
index 823dcc50ee..d20c2266a8 100644
--- a/railties/test/generators/plugin_generator_test.rb
+++ b/railties/test/generators/plugin_generator_test.rb
@@ -1,6 +1,6 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/rails/plugin/plugin_generator'
-require 'generators/shared_generator_tests'
+require "generators/generators_test_helper"
+require "rails/generators/rails/plugin/plugin_generator"
+require "generators/shared_generator_tests"
 
 DEFAULT_PLUGIN_FILES = %w(
   .gitignore
@@ -68,8 +68,8 @@ class PluginGeneratorTest < Rails::Generators::TestCase
       assert_match(/Rails::TestUnitReporter\.executable = 'bin\/test'/, content)
     end
     assert_file "test/bukkits_test.rb", /assert_kind_of Module, Bukkits/
-    assert_file 'bin/test'
-    assert_no_file 'bin/rails'
+    assert_file "bin/test"
+    assert_no_file "bin/rails"
   end
 
   def test_generating_test_files_in_full_mode
@@ -80,7 +80,7 @@ class PluginGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_inclusion_of_a_debugger
-    run_generator [destination_root, '--full']
+    run_generator [destination_root, "--full"]
     if defined?(JRUBY_VERSION) || RUBY_ENGINE == "rbx"
       assert_file "Gemfile" do |content|
         assert_no_match(/byebug/, content)
@@ -101,7 +101,7 @@ class PluginGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_generating_adds_dummy_app_rake_tasks_without_unit_test_files
-    run_generator [destination_root, "-T", "--mountable", '--dummy-path', 'my_dummy_app']
+    run_generator [destination_root, "-T", "--mountable", "--dummy-path", "my_dummy_app"]
     assert_file "Rakefile", /APP_RAKEFILE/
   end
 
@@ -199,13 +199,13 @@ class PluginGeneratorTest < Rails::Generators::TestCase
 
   def test_dev_option
     assert_generates_without_bundler(dev: true)
-    rails_path = File.expand_path('../../..', Rails.root)
-    assert_file 'Gemfile', /^gem\s+["']rails["'],\s+path:\s+["']#{Regexp.escape(rails_path)}["']$/
+    rails_path = File.expand_path("../../..", Rails.root)
+    assert_file "Gemfile", /^gem\s+["']rails["'],\s+path:\s+["']#{Regexp.escape(rails_path)}["']$/
   end
 
   def test_edge_option
     assert_generates_without_bundler(edge: true)
-    assert_file 'Gemfile', %r{^gem\s+["']rails["'],\s+github:\s+["']#{Regexp.escape("rails/rails")}["'],\s+branch:\s+["']#{Regexp.escape("5-0-stable")}["']$}
+    assert_file "Gemfile", %r{^gem\s+["']rails["'],\s+github:\s+["']#{Regexp.escape("rails/rails")}["'],\s+branch:\s+["']#{Regexp.escape("5-0-stable")}["']$}
   end
 
   def test_generation_does_not_run_bundle_install_with_full_and_mountable
@@ -236,21 +236,21 @@ class PluginGeneratorTest < Rails::Generators::TestCase
   def test_ensure_that_tests_work
     run_generator
     FileUtils.cd destination_root
-    quietly { system 'bundle install' }
+    quietly { system "bundle install" }
     assert_match(/1 runs, 1 assertions, 0 failures, 0 errors/, `bin/test 2>&1`)
   end
 
   def test_ensure_that_tests_works_in_full_mode
     run_generator [destination_root, "--full", "--skip_active_record"]
     FileUtils.cd destination_root
-    quietly { system 'bundle install' }
+    quietly { system "bundle install" }
     assert_match(/1 runs, 1 assertions, 0 failures, 0 errors/, `bundle exec rake test 2>&1`)
   end
 
   def test_ensure_that_migration_tasks_work_with_mountable_option
     run_generator [destination_root, "--mountable"]
     FileUtils.cd destination_root
-    quietly { system 'bundle install' }
+    quietly { system "bundle install" }
     output = `bin/rails db:migrate 2>&1`
     assert $?.success?, "Command failed: #{output}"
   end
@@ -333,7 +333,7 @@ class PluginGeneratorTest < Rails::Generators::TestCase
       assert_match(/ActionDispatch::IntegrationTest\.fixture_path = ActiveSupport::TestCase\.fixture_pat/, content)
       assert_no_match(/Rails::TestUnitReporter\.executable = 'bin\/test'/, content)
     end
-    assert_no_file 'bin/test'
+    assert_no_file "bin/test"
   end
 
   def test_create_mountable_application_with_mountable_option_and_hypenated_name
@@ -450,7 +450,7 @@ class PluginGeneratorTest < Rails::Generators::TestCase
     assert_file "spec/dummy/config/application.rb"
     assert_no_file "test"
     assert_no_file "test/test_helper.rb"
-    assert_file '.gitignore' do |contents|
+    assert_file ".gitignore" do |contents|
       assert_match(/spec\/dummy/, contents)
     end
   end
@@ -458,7 +458,7 @@ class PluginGeneratorTest < Rails::Generators::TestCase
   def test_dummy_appplication_skip_listen_by_default
     run_generator
 
-    assert_file 'test/dummy/config/environments/development.rb' do |contents|
+    assert_file "test/dummy/config/environments/development.rb" do |contents|
       assert_match(/^\s*# config.file_watcher = ActiveSupport::EventedFileUpdateChecker/, contents)
     end
   end
@@ -473,21 +473,21 @@ class PluginGeneratorTest < Rails::Generators::TestCase
 
   def test_unnecessary_files_are_not_generated_in_dummy_application
     run_generator
-    assert_no_file 'test/dummy/.gitignore'
-    assert_no_file 'test/dummy/db/seeds.rb'
-    assert_no_file 'test/dummy/Gemfile'
-    assert_no_file 'test/dummy/public/robots.txt'
-    assert_no_file 'test/dummy/README.md'
-    assert_no_directory 'test/dummy/lib/tasks'
-    assert_no_directory 'test/dummy/doc'
-    assert_no_directory 'test/dummy/test'
-    assert_no_directory 'test/dummy/vendor'
+    assert_no_file "test/dummy/.gitignore"
+    assert_no_file "test/dummy/db/seeds.rb"
+    assert_no_file "test/dummy/Gemfile"
+    assert_no_file "test/dummy/public/robots.txt"
+    assert_no_file "test/dummy/README.md"
+    assert_no_directory "test/dummy/lib/tasks"
+    assert_no_directory "test/dummy/doc"
+    assert_no_directory "test/dummy/test"
+    assert_no_directory "test/dummy/vendor"
   end
 
   def test_skipping_test_files
     run_generator [destination_root, "--skip-test"]
     assert_no_file "test"
-    assert_file '.gitignore' do |contents|
+    assert_file ".gitignore" do |contents|
       assert_no_match(/test\dummy/, contents)
     end
   end
@@ -496,7 +496,7 @@ class PluginGeneratorTest < Rails::Generators::TestCase
     run_generator [destination_root, "--skip-gemspec"]
     assert_no_file "bukkits.gemspec"
     assert_file "Gemfile" do |contents|
-      assert_no_match('gemspec', contents)
+      assert_no_match("gemspec", contents)
       assert_match(/gem 'rails'/, contents)
       assert_match_sqlite3(contents)
       assert_no_match(/# gem "jquery-rails"/, contents)
@@ -507,7 +507,7 @@ class PluginGeneratorTest < Rails::Generators::TestCase
     run_generator [destination_root, "--skip-gemspec", "--full"]
     assert_no_file "bukkits.gemspec"
     assert_file "Gemfile" do |contents|
-      assert_no_match('gemspec', contents)
+      assert_no_match("gemspec", contents)
       assert_match(/gem 'rails'/, contents)
       assert_match_sqlite3(contents)
     end
@@ -516,21 +516,21 @@ class PluginGeneratorTest < Rails::Generators::TestCase
   def test_creating_plugin_in_app_directory_adds_gemfile_entry
     # simulate application existence
     gemfile_path = "#{Rails.root}/Gemfile"
-    Object.const_set('APP_PATH', Rails.root)
+    Object.const_set("APP_PATH", Rails.root)
     FileUtils.touch gemfile_path
 
     run_generator
 
     assert_file gemfile_path, /gem 'bukkits', path: 'tmp\/bukkits'/
   ensure
-    Object.send(:remove_const, 'APP_PATH')
+    Object.send(:remove_const, "APP_PATH")
     FileUtils.rm gemfile_path
   end
 
   def test_skipping_gemfile_entry
     # simulate application existence
     gemfile_path = "#{Rails.root}/Gemfile"
-    Object.const_set('APP_PATH', Rails.root)
+    Object.const_set("APP_PATH", Rails.root)
     FileUtils.touch gemfile_path
 
     run_generator [destination_root, "--skip-gemfile-entry"]
@@ -539,7 +539,7 @@ class PluginGeneratorTest < Rails::Generators::TestCase
       assert_no_match(/gem 'bukkits', path: 'tmp\/bukkits'/, contents)
     end
   ensure
-    Object.send(:remove_const, 'APP_PATH')
+    Object.send(:remove_const, "APP_PATH")
     FileUtils.rm gemfile_path
   end
 
@@ -580,7 +580,7 @@ class PluginGeneratorTest < Rails::Generators::TestCase
     name = "TODO: Write your name"
     email = "TODO: Write your email address"
 
-    run_generator [destination_root, '--skip-git']
+    run_generator [destination_root, "--skip-git"]
     assert_file "MIT-LICENSE" do |contents|
       assert_match name, contents
     end
@@ -591,8 +591,8 @@ class PluginGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_skipping_useless_folders_generation_for_api_engines
-    ['--full', '--mountable'].each do |option|
-      run_generator [destination_root, option, '--api']
+    ["--full", "--mountable"].each do |option|
+      run_generator [destination_root, option, "--api"]
 
       assert_no_directory "app/assets"
       assert_no_directory "app/helpers"
@@ -603,7 +603,7 @@ class PluginGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_application_controller_parent_for_mountable_api_plugins
-    run_generator [destination_root, '--mountable', '--api']
+    run_generator [destination_root, "--mountable", "--api"]
 
     assert_file "app/controllers/bukkits/application_controller.rb" do |content|
       assert_match "ApplicationController < ActionController::API", content
@@ -611,7 +611,7 @@ class PluginGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_dummy_api_application_for_api_plugins
-    run_generator [destination_root, '--api']
+    run_generator [destination_root, "--api"]
 
     assert_file "test/dummy/config/application.rb" do |content|
       assert_match "config.api_only = true", content
@@ -620,7 +620,7 @@ class PluginGeneratorTest < Rails::Generators::TestCase
 
 
   def test_api_generators_configuration_for_api_engines
-    run_generator [destination_root, '--full', '--api']
+    run_generator [destination_root, "--full", "--api"]
 
     assert_file "lib/bukkits/engine.rb" do |content|
       assert_match "config.generators.api_only = true", content
@@ -628,7 +628,7 @@ class PluginGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_scaffold_generator_for_mountable_api_plugins
-    run_generator [destination_root, '--mountable', '--api']
+    run_generator [destination_root, "--mountable", "--api"]
 
     capture(:stdout) do
       `#{destination_root}/bin/rails g scaffold article`
@@ -645,7 +645,7 @@ class PluginGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_model_with_existent_application_record_in_mountable_engine
-    run_generator [destination_root, '--mountable']
+    run_generator [destination_root, "--mountable"]
     capture(:stdout) do
       `#{destination_root}/bin/rails g model article`
     end
@@ -654,7 +654,7 @@ class PluginGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_generate_application_record_when_does_not_exist_in_mountable_engine
-    run_generator [destination_root, '--mountable']
+    run_generator [destination_root, "--mountable"]
     FileUtils.rm "#{destination_root}/app/models/bukkits/application_record.rb"
     capture(:stdout) do
       `#{destination_root}/bin/rails g model article`
@@ -668,7 +668,7 @@ class PluginGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_generate_application_mailer_when_does_not_exist_in_mountable_engine
-    run_generator [destination_root, '--mountable']
+    run_generator [destination_root, "--mountable"]
     FileUtils.rm "#{destination_root}/app/mailers/bukkits/application_mailer.rb"
     capture(:stdout) do
       `#{destination_root}/bin/rails g mailer User`
@@ -681,7 +681,7 @@ class PluginGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_generate_mailer_layouts_when_does_not_exist_in_mountable_engine
-    run_generator [destination_root, '--mountable']
+    run_generator [destination_root, "--mountable"]
     capture(:stdout) do
       `#{destination_root}/bin/rails g mailer User`
     end
@@ -696,7 +696,7 @@ class PluginGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_generate_application_job_when_does_not_exist_in_mountable_engine
-    run_generator [destination_root, '--mountable']
+    run_generator [destination_root, "--mountable"]
     FileUtils.rm "#{destination_root}/app/jobs/bukkits/application_job.rb"
     capture(:stdout) do
       `#{destination_root}/bin/rails g job refresh_counters`
@@ -731,9 +731,9 @@ class PluginGeneratorTest < Rails::Generators::TestCase
 
       command_check = -> command do
         case command
-        when 'install'
+        when "install"
           flunk "install expected to not be called"
-        when 'exec spring binstub --all'
+        when "exec spring binstub --all"
           # Called when running tests with spring, let through unscathed.
         end
       end
diff --git a/railties/test/generators/plugin_test_helper.rb b/railties/test/generators/plugin_test_helper.rb
index 96c1b1d31f..8ac90e3484 100644
--- a/railties/test/generators/plugin_test_helper.rb
+++ b/railties/test/generators/plugin_test_helper.rb
@@ -1,5 +1,5 @@
-require 'abstract_unit'
-require 'tmpdir'
+require "abstract_unit"
+require "tmpdir"
 
 module PluginTestHelper
   def create_test_file(name, pass: true)
@@ -15,7 +15,7 @@ module PluginTestHelper
     RUBY
   end
 
-  def plugin_file(path, contents, mode: 'w')
+  def plugin_file(path, contents, mode: "w")
     FileUtils.mkdir_p File.dirname("#{plugin_path}/#{path}")
     File.open("#{plugin_path}/#{path}", mode) do |f|
       f.puts contents
diff --git a/railties/test/generators/plugin_test_runner_test.rb b/railties/test/generators/plugin_test_runner_test.rb
index ef6359fece..04b4b10254 100644
--- a/railties/test/generators/plugin_test_runner_test.rb
+++ b/railties/test/generators/plugin_test_runner_test.rb
@@ -1,12 +1,12 @@
-require 'generators/plugin_test_helper'
+require "generators/plugin_test_helper"
 
 class PluginTestRunnerTest < ActiveSupport::TestCase
   include PluginTestHelper
 
   def setup
-    @destination_root = Dir.mktmpdir('bukkits')
+    @destination_root = Dir.mktmpdir("bukkits")
     Dir.chdir(@destination_root) { `bundle exec rails plugin new bukkits --skip-bundle` }
-    plugin_file 'test/dummy/db/schema.rb', ''
+    plugin_file "test/dummy/db/schema.rb", ""
   end
 
   def teardown
@@ -14,20 +14,20 @@ class PluginTestRunnerTest < ActiveSupport::TestCase
   end
 
   def test_run_single_file
-    create_test_file 'foo'
-    create_test_file 'bar'
+    create_test_file "foo"
+    create_test_file "bar"
     assert_match "1 runs, 1 assertions, 0 failures", run_test_command("test/foo_test.rb")
   end
 
   def test_run_multiple_files
-    create_test_file 'foo'
-    create_test_file 'bar'
+    create_test_file "foo"
+    create_test_file "bar"
     assert_match "2 runs, 2 assertions, 0 failures", run_test_command("test/foo_test.rb test/bar_test.rb")
   end
 
   def test_mix_files_and_line_filters
-    create_test_file 'account'
-    plugin_file 'test/post_test.rb', <<-RUBY
+    create_test_file "account"
+    plugin_file "test/post_test.rb", <<-RUBY
       require 'test_helper'
 
       class PostTest < ActiveSupport::TestCase
@@ -42,47 +42,47 @@ class PluginTestRunnerTest < ActiveSupport::TestCase
       end
     RUBY
 
-    run_test_command('test/account_test.rb test/post_test.rb:4').tap do |output|
-      assert_match 'AccountTest', output
-      assert_match 'PostTest', output
-      assert_match '2 runs, 2 assertions', output
+    run_test_command("test/account_test.rb test/post_test.rb:4").tap do |output|
+      assert_match "AccountTest", output
+      assert_match "PostTest", output
+      assert_match "2 runs, 2 assertions", output
     end
   end
 
   def test_multiple_line_filters
-    create_test_file 'account'
-    create_test_file 'post'
+    create_test_file "account"
+    create_test_file "post"
 
-    run_test_command('test/account_test.rb:4 test/post_test.rb:4').tap do |output|
-      assert_match 'AccountTest', output
-      assert_match 'PostTest', output
+    run_test_command("test/account_test.rb:4 test/post_test.rb:4").tap do |output|
+      assert_match "AccountTest", output
+      assert_match "PostTest", output
     end
   end
 
   def test_output_inline_by_default
-    create_test_file 'post', pass: false
+    create_test_file "post", pass: false
 
-    output = run_test_command('test/post_test.rb')
+    output = run_test_command("test/post_test.rb")
     expect = %r{Running:\n\nPostTest\nF\n\nFailure:\nPostTest#test_truth \[[^\]]+test/post_test.rb:6\]:\nwups!\n\nbin/test (/private)?#{plugin_path}/test/post_test.rb:4}
     assert_match expect, output
   end
 
   def test_only_inline_failure_output
-    create_test_file 'post', pass: false
+    create_test_file "post", pass: false
 
-    output = run_test_command('test/post_test.rb')
+    output = run_test_command("test/post_test.rb")
     assert_match %r{Finished in.*\n\n1 runs, 1 assertions}, output
   end
 
   def test_fail_fast
-    create_test_file 'post', pass: false
+    create_test_file "post", pass: false
 
     assert_match(/Interrupt/,
-      capture(:stderr) { run_test_command('test/post_test.rb --fail-fast') })
+      capture(:stderr) { run_test_command("test/post_test.rb --fail-fast") })
   end
 
   def test_raise_error_when_specified_file_does_not_exist
-    error = capture(:stderr) { run_test_command('test/not_exists.rb') }
+    error = capture(:stderr) { run_test_command("test/not_exists.rb") }
     assert_match(%r{cannot load such file.+test/not_exists\.rb}, error)
   end
 
diff --git a/railties/test/generators/resource_generator_test.rb b/railties/test/generators/resource_generator_test.rb
index 53dcfc4024..e976e58180 100644
--- a/railties/test/generators/resource_generator_test.rb
+++ b/railties/test/generators/resource_generator_test.rb
@@ -1,5 +1,5 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/rails/resource/resource_generator'
+require "generators/generators_test_helper"
+require "rails/generators/rails/resource/resource_generator"
 
 class ResourceGeneratorTest < Rails::Generators::TestCase
   include GeneratorsTestHelper
diff --git a/railties/test/generators/scaffold_controller_generator_test.rb b/railties/test/generators/scaffold_controller_generator_test.rb
index 736ff0b41f..bd23faf268 100644
--- a/railties/test/generators/scaffold_controller_generator_test.rb
+++ b/railties/test/generators/scaffold_controller_generator_test.rb
@@ -1,5 +1,5 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/rails/scaffold_controller/scaffold_controller_generator'
+require "generators/generators_test_helper"
+require "rails/generators/rails/scaffold_controller/scaffold_controller_generator"
 
 module Unknown
   module Generators
diff --git a/railties/test/generators/scaffold_generator_test.rb b/railties/test/generators/scaffold_generator_test.rb
index bd69906b9d..c1f3e7b52d 100644
--- a/railties/test/generators/scaffold_generator_test.rb
+++ b/railties/test/generators/scaffold_generator_test.rb
@@ -1,5 +1,5 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/rails/scaffold/scaffold_generator'
+require "generators/generators_test_helper"
+require "rails/generators/rails/scaffold/scaffold_generator"
 
 class ScaffoldGeneratorTest < Rails::Generators::TestCase
   include GeneratorsTestHelper
@@ -74,8 +74,8 @@ class ScaffoldGeneratorTest < Rails::Generators::TestCase
     end
 
     assert_file "app/views/product_lines/_form.html.erb" do |test|
-      assert_match 'product_line', test
-      assert_no_match '@product_line', test
+      assert_match "product_line", test
+      assert_no_match "@product_line", test
     end
 
     # Helpers
@@ -322,8 +322,8 @@ class ScaffoldGeneratorTest < Rails::Generators::TestCase
     content = File.read(route_path)
 
     # Remove all of the comments and blank lines from the routes file
-    content.gsub!(/^  \#.*\n/, '')
-    content.gsub!(/^\n/, '')
+    content.gsub!(/^  \#.*\n/, "")
+    content.gsub!(/^\n/, "")
 
     File.open(route_path, "wb") { |file| file.write(content) }
     assert_file "config/routes.rb", /\.routes\.draw do\n  resources :product_lines\nend\n\z/
diff --git a/railties/test/generators/shared_generator_tests.rb b/railties/test/generators/shared_generator_tests.rb
index 03ea521355..766162b625 100644
--- a/railties/test/generators/shared_generator_tests.rb
+++ b/railties/test/generators/shared_generator_tests.rb
@@ -5,7 +5,7 @@ module SharedGeneratorTests
   def setup
     Rails.application = TestApp::Application
     super
-    Rails::Generators::AppGenerator.instance_variable_set('@desc', nil)
+    Rails::Generators::AppGenerator.instance_variable_set("@desc", nil)
 
     Kernel::silence_warnings do
       Thor::Base.shell.send(:attr_accessor, :always_force)
@@ -16,7 +16,7 @@ module SharedGeneratorTests
 
   def teardown
     super
-    Rails::Generators::AppGenerator.instance_variable_set('@desc', nil)
+    Rails::Generators::AppGenerator.instance_variable_set("@desc", nil)
     Rails.application = TestApp::Application.instance
   end
 
@@ -81,7 +81,7 @@ module SharedGeneratorTests
     template.instance_eval "def read; self; end" # Make the string respond to read
 
     check_open = -> *args do
-      assert_equal [ path, 'Accept' => 'application/x-thor-template' ], args
+      assert_equal [ path, "Accept" => "application/x-thor-template" ], args
       template
     end
 
@@ -93,7 +93,7 @@ module SharedGeneratorTests
   def test_skip_gemfile
     assert_not_called(generator([destination_root], skip_gemfile: true), :bundle_command) do
       quietly { generator.invoke_all }
-      assert_no_file 'Gemfile'
+      assert_no_file "Gemfile"
     end
   end
 
@@ -102,22 +102,22 @@ module SharedGeneratorTests
       quietly { generator.invoke_all }
       # skip_bundle is only about running bundle install, ensure the Gemfile is still
       # generated.
-      assert_file 'Gemfile'
+      assert_file "Gemfile"
     end
   end
 
   def test_skip_git
-    run_generator [destination_root, '--skip-git', '--full']
-    assert_no_file('.gitignore')
+    run_generator [destination_root, "--skip-git", "--full"]
+    assert_no_file(".gitignore")
   end
 
   def test_skip_keeps
-    run_generator [destination_root, '--skip-keeps', '--full']
+    run_generator [destination_root, "--skip-keeps", "--full"]
 
-    assert_file '.gitignore' do |content|
+    assert_file ".gitignore" do |content|
       assert_no_match(/\.keep/, content)
     end
 
-    assert_no_file('app/models/concerns/.keep')
+    assert_no_file("app/models/concerns/.keep")
   end
 end
diff --git a/railties/test/generators/task_generator_test.rb b/railties/test/generators/task_generator_test.rb
index d5bd44b9db..2285534bb9 100644
--- a/railties/test/generators/task_generator_test.rb
+++ b/railties/test/generators/task_generator_test.rb
@@ -1,5 +1,5 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/rails/task/task_generator'
+require "generators/generators_test_helper"
+require "rails/generators/rails/task/task_generator"
 
 class TaskGeneratorTest < Rails::Generators::TestCase
   include GeneratorsTestHelper
@@ -15,10 +15,10 @@ class TaskGeneratorTest < Rails::Generators::TestCase
   end
 
   def test_task_on_revoke
-    task_path = 'lib/tasks/feeds.rake'
+    task_path = "lib/tasks/feeds.rake"
     run_generator
     assert_file task_path
-    run_generator ['feeds'], behavior: :revoke
+    run_generator ["feeds"], behavior: :revoke
     assert_no_file task_path
   end
 end
diff --git a/railties/test/generators/test_runner_in_engine_test.rb b/railties/test/generators/test_runner_in_engine_test.rb
index d37e261fbb..4b5fb3ba3f 100644
--- a/railties/test/generators/test_runner_in_engine_test.rb
+++ b/railties/test/generators/test_runner_in_engine_test.rb
@@ -1,12 +1,12 @@
-require 'generators/plugin_test_helper'
+require "generators/plugin_test_helper"
 
 class TestRunnerInEngineTest < ActiveSupport::TestCase
   include PluginTestHelper
 
   def setup
-    @destination_root = Dir.mktmpdir('bukkits')
+    @destination_root = Dir.mktmpdir("bukkits")
     Dir.chdir(@destination_root) { `bundle exec rails plugin new bukkits --full --skip-bundle` }
-    plugin_file 'test/dummy/db/schema.rb', ''
+    plugin_file "test/dummy/db/schema.rb", ""
   end
 
   def teardown
@@ -14,9 +14,9 @@ class TestRunnerInEngineTest < ActiveSupport::TestCase
   end
 
   def test_rerun_snippet_is_relative_path
-    create_test_file 'post', pass: false
+    create_test_file "post", pass: false
 
-    output = run_test_command('test/post_test.rb')
+    output = run_test_command("test/post_test.rb")
     expect = %r{Running:\n\nPostTest\nF\n\nFailure:\nPostTest#test_truth \[[^\]]+test/post_test.rb:6\]:\nwups!\n\nbin/rails test test/post_test.rb:4}
     assert_match expect, output
   end
diff --git a/railties/test/generators_test.rb b/railties/test/generators_test.rb
index 291415858c..83c1d6811c 100644
--- a/railties/test/generators_test.rb
+++ b/railties/test/generators_test.rb
@@ -1,6 +1,6 @@
-require 'generators/generators_test_helper'
-require 'rails/generators/rails/model/model_generator'
-require 'rails/generators/test_unit/model/model_generator'
+require "generators/generators_test_helper"
+require "rails/generators/rails/model/model_generator"
+require "rails/generators/test_unit/model/model_generator"
 
 class GeneratorsTest < Rails::Generators::TestCase
   include GeneratorsTestHelper
@@ -15,7 +15,7 @@ class GeneratorsTest < Rails::Generators::TestCase
   end
 
   def test_simple_invoke
-    assert File.exist?(File.join(@path, 'generators', 'model_generator.rb'))
+    assert File.exist?(File.join(@path, "generators", "model_generator.rb"))
     assert_called_with(TestUnit::Generators::ModelGenerator, :start, [["Account"], {}]) do
       Rails::Generators.invoke("test_unit:model", ["Account"])
     end
@@ -46,7 +46,7 @@ class GeneratorsTest < Rails::Generators::TestCase
   end
 
   def test_should_give_higher_preference_to_rails_generators
-    assert File.exist?(File.join(@path, 'generators', 'model_generator.rb'))
+    assert File.exist?(File.join(@path, "generators", "model_generator.rb"))
     assert_called_with(Rails::Generators::ModelGenerator, :start, [["Account"], {}]) do
       warnings = capture(:stderr){ Rails::Generators.invoke :model, ["Account"] }
       assert warnings.empty?
@@ -108,8 +108,8 @@ class GeneratorsTest < Rails::Generators::TestCase
   def test_invoke_with_nested_namespaces
     model_generator = Minitest::Mock.new
     model_generator.expect(:start, nil, [["Account"], {}])
-    assert_called_with(Rails::Generators, :find_by_namespace, ['namespace', 'my:awesome'], returns: model_generator) do
-      Rails::Generators.invoke 'my:awesome:namespace', ["Account"]
+    assert_called_with(Rails::Generators, :find_by_namespace, ["namespace", "my:awesome"], returns: model_generator) do
+      Rails::Generators.invoke "my:awesome:namespace", ["Account"]
     end
     model_generator.verify
   end
@@ -214,7 +214,7 @@ class GeneratorsTest < Rails::Generators::TestCase
 
     # Create template
     mkdir_p(File.dirname(template))
-    File.open(template, 'w'){ |f| f.write "empty" }
+    File.open(template, "w"){ |f| f.write "empty" }
 
     capture(:stdout) do
       Rails::Generators.invoke :model, ["user"], destination_root: destination_root
@@ -234,7 +234,7 @@ class GeneratorsTest < Rails::Generators::TestCase
 
   def test_usage_with_embedded_ruby
     require File.expand_path("fixtures/lib/generators/usage_template/usage_template_generator", File.dirname(__FILE__))
-    output = capture(:stdout) { Rails::Generators.invoke :usage_template, ['--help'] }
+    output = capture(:stdout) { Rails::Generators.invoke :usage_template, ["--help"] }
     assert_match(/:: 2 ::/, output)
   end
 
diff --git a/railties/test/initializable_test.rb b/railties/test/initializable_test.rb
index d4eafebfa4..34fe395bf7 100644
--- a/railties/test/initializable_test.rb
+++ b/railties/test/initializable_test.rb
@@ -1,5 +1,5 @@
-require 'abstract_unit'
-require 'rails/initializable'
+require "abstract_unit"
+require "rails/initializable"
 
 module InitializableTests
 
@@ -220,8 +220,8 @@ module InitializableTests
   class WithArgsTest < ActiveSupport::TestCase
     test "running initializers with args" do
       $with_arg = nil
-      WithArgs.new.run_initializers(:default, 'foo')
-      assert_equal 'foo', $with_arg
+      WithArgs.new.run_initializers(:default, "foo")
+      assert_equal "foo", $with_arg
     end
   end
 
diff --git a/railties/test/isolation/abstract_unit.rb b/railties/test/isolation/abstract_unit.rb
index 5528459ad2..fb3818b92c 100644
--- a/railties/test/isolation/abstract_unit.rb
+++ b/railties/test/isolation/abstract_unit.rb
@@ -6,13 +6,13 @@
 #
 # It is also good to know what is the bare minimum to get
 # Rails booted up.
-require 'fileutils'
+require "fileutils"
 
-require 'bundler/setup' unless defined?(Bundler)
-require 'active_support'
-require 'active_support/testing/autorun'
-require 'active_support/testing/stream'
-require 'active_support/test_case'
+require "bundler/setup" unless defined?(Bundler)
+require "active_support"
+require "active_support/testing/autorun"
+require "active_support/testing/stream"
+require "active_support/test_case"
 
 RAILS_FRAMEWORK_ROOT = File.expand_path("#{File.dirname(__FILE__)}/../../..")
 
@@ -21,12 +21,12 @@ RAILS_FRAMEWORK_ROOT = File.expand_path("#{File.dirname(__FILE__)}/../../..")
 require "active_support/core_ext/object/blank"
 require "active_support/testing/isolation"
 require "active_support/core_ext/kernel/reporting"
-require 'tmpdir'
+require "tmpdir"
 
 module TestHelpers
   module Paths
     def app_template_path
-      File.join Dir.tmpdir, 'app_template'
+      File.join Dir.tmpdir, "app_template"
     end
 
     def tmp_path(*args)
@@ -78,8 +78,8 @@ module TestHelpers
       resp = Array(resp)
 
       assert_equal 200, resp[0]
-      assert_match 'text/html', resp[1]["Content-Type"]
-      assert_match 'charset=utf-8', resp[1]["Content-Type"]
+      assert_match "text/html", resp[1]["Content-Type"]
+      assert_match "charset=utf-8", resp[1]["Content-Type"]
       assert extract_body(resp).match(/Yay! You.*re on Rails!/)
     end
 
@@ -103,9 +103,9 @@ module TestHelpers
   module Generation
     # Build an application by invoking the generator and going through the whole stack.
     def build_app(options = {})
-      @prev_rails_env = ENV['RAILS_ENV']
-      ENV['RAILS_ENV']       =   "development"
-      ENV['SECRET_KEY_BASE'] ||= SecureRandom.hex(16)
+      @prev_rails_env = ENV["RAILS_ENV"]
+      ENV["RAILS_ENV"]       =   "development"
+      ENV["SECRET_KEY_BASE"] ||= SecureRandom.hex(16)
 
       FileUtils.rm_rf(app_path)
       FileUtils.cp_r(app_template_path, app_path)
@@ -124,7 +124,7 @@ module TestHelpers
 
       routes = File.read("#{app_path}/config/routes.rb")
       if routes =~ /(\n\s*end\s*)\Z/
-        File.open("#{app_path}/config/routes.rb", 'w') do |f|
+        File.open("#{app_path}/config/routes.rb", "w") do |f|
           f.puts $` + "\nActiveSupport::Deprecation.silence { match ':controller(/:action(/:id))(.:format)', via: :all }\n" + $1
         end
       end
@@ -158,7 +158,7 @@ module TestHelpers
     end
 
     def teardown_app
-      ENV['RAILS_ENV'] = @prev_rails_env if @prev_rails_env
+      ENV["RAILS_ENV"] = @prev_rails_env if @prev_rails_env
     end
 
     # Make a very basic app, without creating the whole directory structure.
@@ -167,7 +167,7 @@ module TestHelpers
       require "rails"
       require "action_controller/railtie"
       require "action_view/railtie"
-      require 'action_dispatch/middleware/flash'
+      require "action_dispatch/middleware/flash"
 
       @app = Class.new(Rails::Application)
       @app.config.eager_load = false
@@ -184,7 +184,7 @@ module TestHelpers
         get "/" => "omg#index"
       end
 
-      require 'rack/test'
+      require "rack/test"
       extend ::Rack::Test::Methods
     end
 
@@ -197,7 +197,7 @@ module TestHelpers
         end
       RUBY
 
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get ':controller(/:action)'
         end
@@ -230,7 +230,7 @@ module TestHelpers
       app.insert(2, "$:.unshift(\"#{dir}/lib\")")
       app.insert(3, "require #{name.inspect}")
 
-      File.open("#{app_path}/config/application.rb", 'r+') do |f|
+      File.open("#{app_path}/config/application.rb", "r+") do |f|
         f.puts app
       end
 
@@ -248,7 +248,7 @@ module TestHelpers
     def add_to_top_of_config(str)
       environment = File.read("#{app_path}/config/application.rb")
       if environment =~ /(Rails::Application\s*)/
-        File.open("#{app_path}/config/application.rb", 'w') do |f|
+        File.open("#{app_path}/config/application.rb", "w") do |f|
           f.puts $` + $1 + "\n#{str}\n" + $'
         end
       end
@@ -257,7 +257,7 @@ module TestHelpers
     def add_to_config(str)
       environment = File.read("#{app_path}/config/application.rb")
       if environment =~ /(\n\s*end\s*end\s*)\Z/
-        File.open("#{app_path}/config/application.rb", 'w') do |f|
+        File.open("#{app_path}/config/application.rb", "w") do |f|
           f.puts $` + "\n#{str}\n" + $1
         end
       end
@@ -266,7 +266,7 @@ module TestHelpers
     def add_to_env_config(env, str)
       environment = File.read("#{app_path}/config/environments/#{env}.rb")
       if environment =~ /(\n\s*end\s*)\Z/
-        File.open("#{app_path}/config/environments/#{env}.rb", 'w') do |f|
+        File.open("#{app_path}/config/environments/#{env}.rb", "w") do |f|
           f.puts $` + "\n#{str}\n" + $1
         end
       end
@@ -282,11 +282,11 @@ module TestHelpers
 
     def remove_from_file(file, str)
       contents = File.read(file)
-      contents.sub!(/#{str}/, '')
+      contents.sub!(/#{str}/, "")
       File.write(file, contents)
     end
 
-    def app_file(path, contents, mode = 'w')
+    def app_file(path, contents, mode = "w")
       FileUtils.mkdir_p File.dirname("#{app_path}/#{path}")
       File.open("#{app_path}/#{path}", mode) do |f|
         f.puts contents
@@ -305,7 +305,7 @@ module TestHelpers
       to_remove = [:actionmailer, :activerecord] - arr
 
       if to_remove.include?(:activerecord)
-        remove_from_config 'config.active_record.*'
+        remove_from_config "config.active_record.*"
       end
 
       $:.reject! {|path| path =~ %r'/(#{to_remove.join('|')})/' }
@@ -331,7 +331,7 @@ Module.new do
   FileUtils.mkdir(app_template_path)
 
   `#{Gem.ruby} #{RAILS_FRAMEWORK_ROOT}/railties/exe/rails new #{app_template_path} --skip-gemfile --skip-listen --no-rc`
-  File.open("#{app_template_path}/config/boot.rb", 'w') do |f|
+  File.open("#{app_template_path}/config/boot.rb", "w") do |f|
     f.puts "require 'rails/all'"
   end
 end unless defined?(RAILS_ISOLATED_ENGINE)
diff --git a/railties/test/path_generation_test.rb b/railties/test/path_generation_test.rb
index a16adc72a6..71aab479e5 100644
--- a/railties/test/path_generation_test.rb
+++ b/railties/test/path_generation_test.rb
@@ -1,6 +1,6 @@
-require 'abstract_unit'
-require 'active_support/core_ext/object/with_options'
-require 'active_support/core_ext/object/json'
+require "abstract_unit"
+require "active_support/core_ext/object/with_options"
+require "active_support/core_ext/object/json"
 
 class PathGenerationTest < ActiveSupport::TestCase
   attr_reader :app
@@ -38,11 +38,11 @@ class PathGenerationTest < ActiveSupport::TestCase
     host = uri_or_host.host unless path
     path ||= uri_or_host.path
 
-    params = {'PATH_INFO'      => path,
-              'REQUEST_METHOD' => method,
-              'HTTP_HOST'      => host }
+    params = {"PATH_INFO"      => path,
+              "REQUEST_METHOD" => method,
+              "HTTP_HOST"      => host }
 
-    params['SCRIPT_NAME'] = script_name if script_name
+    params["SCRIPT_NAME"] = script_name if script_name
 
     status, headers, body = app.call(params)
     new_body = []
@@ -72,11 +72,11 @@ class PathGenerationTest < ActiveSupport::TestCase
 
     url = URI("http://example.org/blogs")
 
-    send_request(url, 'GET', nil, '/FOO')
-    assert_equal '/FOO/blogs', app.instance.controller.blogs_path
+    send_request(url, "GET", nil, "/FOO")
+    assert_equal "/FOO/blogs", app.instance.controller.blogs_path
 
-    send_request(url, 'GET', nil)
-    assert_equal '/blogs', app.instance.controller.blogs_path
+    send_request(url, "GET", nil)
+    assert_equal "/blogs", app.instance.controller.blogs_path
   ensure
     Rails.logger = original_logger
   end
diff --git a/railties/test/paths_test.rb b/railties/test/paths_test.rb
index 96b54c7264..5e96f9f32f 100644
--- a/railties/test/paths_test.rb
+++ b/railties/test/paths_test.rb
@@ -1,6 +1,6 @@
-require 'abstract_unit'
-require 'rails/paths'
-require 'minitest/mock'
+require "abstract_unit"
+require "rails/paths"
+require "minitest/mock"
 
 class PathsTest < ActiveSupport::TestCase
   def setup
diff --git a/railties/test/rack_logger_test.rb b/railties/test/rack_logger_test.rb
index fcc79b57fb..e14eff41ce 100644
--- a/railties/test/rack_logger_test.rb
+++ b/railties/test/rack_logger_test.rb
@@ -1,8 +1,8 @@
-require 'abstract_unit'
-require 'active_support/testing/autorun'
-require 'active_support/test_case'
-require 'rails/rack/logger'
-require 'logger'
+require "abstract_unit"
+require "active_support/testing/autorun"
+require "active_support/test_case"
+require "rails/rack/logger"
+require "logger"
 
 module Rails
   module Rack
@@ -39,7 +39,7 @@ module Rails
       def setup
         @subscriber = Subscriber.new
         @notifier = ActiveSupport::Notifications.notifier
-        @subscription = notifier.subscribe 'request.action_dispatch', subscriber
+        @subscription = notifier.subscribe "request.action_dispatch", subscriber
       end
 
       def teardown
@@ -49,9 +49,9 @@ module Rails
       def test_notification
         logger = TestLogger.new { }
 
-        assert_difference('subscriber.starts.length') do
-          assert_difference('subscriber.finishes.length') do
-            logger.call('REQUEST_METHOD' => 'GET').last.close
+        assert_difference("subscriber.starts.length") do
+          assert_difference("subscriber.finishes.length") do
+            logger.call("REQUEST_METHOD" => "GET").last.close
           end
         end
       end
@@ -62,10 +62,10 @@ module Rails
           raise NotImplementedError
         end
 
-        assert_difference('subscriber.starts.length') do
-          assert_difference('subscriber.finishes.length') do
+        assert_difference("subscriber.starts.length") do
+          assert_difference("subscriber.finishes.length") do
             assert_raises(NotImplementedError) do
-              logger.call 'REQUEST_METHOD' => 'GET'
+              logger.call "REQUEST_METHOD" => "GET"
             end
           end
         end
diff --git a/railties/test/rails_info_controller_test.rb b/railties/test/rails_info_controller_test.rb
index 2e10d63599..d795629ccd 100644
--- a/railties/test/rails_info_controller_test.rb
+++ b/railties/test/rails_info_controller_test.rb
@@ -1,4 +1,4 @@
-require 'abstract_unit'
+require "abstract_unit"
 
 module ActionController
   class Base
@@ -11,8 +11,8 @@ class InfoControllerTest < ActionController::TestCase
 
   def setup
     Rails.application.routes.draw do
-      get '/rails/info/properties' => "rails/info#properties"
-      get '/rails/info/routes'     => "rails/info#routes"
+      get "/rails/info/properties" => "rails/info#properties"
+      get "/rails/info/routes"     => "rails/info#routes"
     end
     @routes = Rails.application.routes
 
@@ -30,7 +30,7 @@ class InfoControllerTest < ActionController::TestCase
   test "info controller renders an error message when request was forbidden" do
     @request.env["REMOTE_ADDR"] = "example.org"
     get :properties
-    assert_select 'p'
+    assert_select "p"
   end
 
   test "info controller allows requests when all requests are considered local" do
@@ -45,7 +45,7 @@ class InfoControllerTest < ActionController::TestCase
 
   test "info controller renders a table with properties" do
     get :properties
-    assert_select 'table'
+    assert_select "table"
   end
 
   test "info controller renders with routes" do
@@ -54,29 +54,29 @@ class InfoControllerTest < ActionController::TestCase
   end
 
   test "info controller returns exact matches" do
-    exact_count = -> { JSON(response.body)['exact'].size }
+    exact_count = -> { JSON(response.body)["exact"].size }
 
-    get :routes, params: { path: 'rails/info/route' }
-    assert exact_count.call == 0, 'should not match incomplete routes'
+    get :routes, params: { path: "rails/info/route" }
+    assert exact_count.call == 0, "should not match incomplete routes"
 
-    get :routes, params: { path: 'rails/info/routes' }
-    assert exact_count.call == 1, 'should match complete routes'
+    get :routes, params: { path: "rails/info/routes" }
+    assert exact_count.call == 1, "should match complete routes"
 
-    get :routes, params: { path: 'rails/info/routes.html' }
-    assert exact_count.call == 1, 'should match complete routes with optional parts'
+    get :routes, params: { path: "rails/info/routes.html" }
+    assert exact_count.call == 1, "should match complete routes with optional parts"
   end
 
   test "info controller returns fuzzy matches" do
-    fuzzy_count = -> { JSON(response.body)['fuzzy'].size }
+    fuzzy_count = -> { JSON(response.body)["fuzzy"].size }
 
-    get :routes, params: { path: 'rails/info' }
-    assert fuzzy_count.call == 2, 'should match incomplete routes'
+    get :routes, params: { path: "rails/info" }
+    assert fuzzy_count.call == 2, "should match incomplete routes"
 
-    get :routes, params: { path: 'rails/info/routes' }
-    assert fuzzy_count.call == 1, 'should match complete routes'
+    get :routes, params: { path: "rails/info/routes" }
+    assert fuzzy_count.call == 1, "should match complete routes"
 
-    get :routes, params: { path: 'rails/info/routes.html' }
-    assert fuzzy_count.call == 0, 'should match optional parts of route literally'
+    get :routes, params: { path: "rails/info/routes.html" }
+    assert fuzzy_count.call == 0, "should match optional parts of route literally"
   end
 
   test "internal routes do not have a default params[:internal] value" do
diff --git a/railties/test/rails_info_test.rb b/railties/test/rails_info_test.rb
index 92e4af25b5..3c893fb3e0 100644
--- a/railties/test/rails_info_test.rb
+++ b/railties/test/rails_info_test.rb
@@ -1,4 +1,4 @@
-require 'abstract_unit'
+require "abstract_unit"
 
 unless defined?(Rails) && defined?(Rails::Info)
   module Rails
@@ -11,45 +11,45 @@ require "active_support/core_ext/kernel/reporting"
 class InfoTest < ActiveSupport::TestCase
   def setup
     Rails.send :remove_const, :Info
-    silence_warnings { load 'rails/info.rb' }
+    silence_warnings { load "rails/info.rb" }
   end
 
   def test_property_with_block_swallows_exceptions_and_ignores_property
     assert_nothing_raised do
       Rails::Info.module_eval do
-        property('Bogus') {raise}
+        property("Bogus") {raise}
       end
     end
-    assert !property_defined?('Bogus')
+    assert !property_defined?("Bogus")
   end
 
   def test_property_with_string
     Rails::Info.module_eval do
-      property 'Hello', 'World'
+      property "Hello", "World"
     end
-    assert_property 'Hello', 'World'
+    assert_property "Hello", "World"
   end
 
   def test_property_with_block
     Rails::Info.module_eval do
-      property('Goodbye') {'World'}
+      property("Goodbye") {"World"}
     end
-    assert_property 'Goodbye', 'World'
+    assert_property "Goodbye", "World"
   end
 
   def test_rails_version
-    assert_property 'Rails version',
-      File.read(File.realpath('../../../RAILS_VERSION', __FILE__)).chomp
+    assert_property "Rails version",
+      File.read(File.realpath("../../../RAILS_VERSION", __FILE__)).chomp
   end
 
   def test_html_includes_middleware
     Rails::Info.module_eval do
-      property 'Middleware', ['Rack::Lock', 'Rack::Static']
+      property "Middleware", ["Rack::Lock", "Rack::Static"]
     end
 
     html = Rails::Info.to_html
     assert html.include?('<tr><td class="name">Middleware</td>')
-    properties.value_for('Middleware').each do |value|
+    properties.value_for("Middleware").each do |value|
       assert html.include?("<li>#{CGI.escapeHTML(value)}</li>")
     end
   end
diff --git a/railties/test/railties/engine_test.rb b/railties/test/railties/engine_test.rb
index fb8de84e1b..0ecabe95fa 100644
--- a/railties/test/railties/engine_test.rb
+++ b/railties/test/railties/engine_test.rb
@@ -109,7 +109,7 @@ module RailtiesTest
       end
     end
 
-    test 'respects the order of railties when installing migrations' do
+    test "respects the order of railties when installing migrations" do
       @blog = engine "blog" do |plugin|
         plugin.write "lib/blog.rb", <<-RUBY
           module Blog
@@ -210,11 +210,11 @@ module RailtiesTest
 
     test "no rake task without migrations" do
       boot_rails
-      require 'rake'
-      require 'rdoc/task'
-      require 'rake/testtask'
+      require "rake"
+      require "rdoc/task"
+      require "rake/testtask"
       Rails.application.load_tasks
-      assert !Rake::Task.task_defined?('bukkits:install:migrations')
+      assert !Rake::Task.task_defined?("bukkits:install:migrations")
     end
 
     test "puts its lib directory on load path" do
@@ -356,11 +356,11 @@ module RailtiesTest
 
       boot_rails
 
-      get '/foo'
-      assert_equal 'foo', last_response.body
+      get "/foo"
+      assert_equal "foo", last_response.body
 
-      get '/bar'
-      assert_equal 'bar', last_response.body
+      get "/bar"
+      assert_equal "bar", last_response.body
     end
 
     test "rake tasks lib tasks are loaded" do
@@ -372,9 +372,9 @@ module RailtiesTest
       RUBY
 
       boot_rails
-      require 'rake'
-      require 'rdoc/task'
-      require 'rake/testtask'
+      require "rake"
+      require "rdoc/task"
+      require "rake/testtask"
       Rails.application.load_tasks
       Rake::Task[:foo].invoke
       assert $executed
@@ -385,18 +385,18 @@ module RailtiesTest
         config.i18n.load_path << "#{app_path}/app/locales/en.yml"
       RUBY
 
-      app_file 'app/locales/en.yml', <<-YAML
+      app_file "app/locales/en.yml", <<-YAML
 en:
   bar: "1"
 YAML
 
-      app_file 'config/locales/en.yml', <<-YAML
+      app_file "config/locales/en.yml", <<-YAML
 en:
   foo: "2"
   bar: "2"
 YAML
 
-      @plugin.write 'config/locales/en.yml', <<-YAML
+      @plugin.write "config/locales/en.yml", <<-YAML
 en:
   foo: "3"
 YAML
@@ -628,11 +628,11 @@ YAML
 
       env = Rack::MockRequest.env_for("/")
       Bukkits::Engine.call(env)
-      assert_equal Bukkits::Engine.routes, env['action_dispatch.routes']
+      assert_equal Bukkits::Engine.routes, env["action_dispatch.routes"]
 
       env = Rack::MockRequest.env_for("/")
       Rails.application.call(env)
-      assert_equal Rails.application.routes, env['action_dispatch.routes']
+      assert_equal Rails.application.routes, env["action_dispatch.routes"]
     end
 
     test "isolated engine should include only its own routes and helpers" do
@@ -1019,7 +1019,7 @@ YAML
 
       # check expanding paths
       engine_dir = @plugin.path.chomp("/").split("/").last
-      engine_path = File.join(@plugin.path, '..', engine_dir)
+      engine_path = File.join(@plugin.path, "..", engine_dir)
       assert_equal Bukkits::Engine.instance, Rails::Engine.find(engine_path)
     end
 
@@ -1288,11 +1288,11 @@ YAML
 
       boot_rails
 
-      get("/bukkits/bukkit", {}, {'SCRIPT_NAME' => '/foo'})
-      assert_equal '/foo/bar', last_response.body
+      get("/bukkits/bukkit", {}, {"SCRIPT_NAME" => "/foo"})
+      assert_equal "/foo/bar", last_response.body
 
-      get("/bar", {}, {'SCRIPT_NAME' => '/foo'})
-      assert_equal '/foo/bukkits/bukkit', last_response.body
+      get("/bar", {}, {"SCRIPT_NAME" => "/foo"})
+      assert_equal "/foo/bukkits/bukkit", last_response.body
     end
 
     test "paths are properly generated when application is mounted at sub-path and relative_url_root is set" do
@@ -1337,11 +1337,11 @@ YAML
 
       boot_rails
 
-      get("/bukkits/bukkit", {}, {'SCRIPT_NAME' => '/foo'})
-      assert_equal '/foo/bar', last_response.body
+      get("/bukkits/bukkit", {}, {"SCRIPT_NAME" => "/foo"})
+      assert_equal "/foo/bar", last_response.body
 
-      get("/bar", {}, {'SCRIPT_NAME' => '/foo'})
-      assert_equal '/foo/bukkits/bukkit', last_response.body
+      get("/bar", {}, {"SCRIPT_NAME" => "/foo"})
+      assert_equal "/foo/bukkits/bukkit", last_response.body
     end
 
   private
diff --git a/railties/test/railties/generators_test.rb b/railties/test/railties/generators_test.rb
index b85e16c040..732898d0c0 100644
--- a/railties/test/railties/generators_test.rb
+++ b/railties/test/railties/generators_test.rb
@@ -1,7 +1,7 @@
 RAILS_ISOLATED_ENGINE = true
 require "isolation/abstract_unit"
 
-require 'generators/generators_test_helper'
+require "generators/generators_test_helper"
 require "rails/generators/test_case"
 
 module RailtiesTests
@@ -9,7 +9,7 @@ module RailtiesTests
     include ActiveSupport::Testing::Isolation
 
     def destination_root
-      tmp_path 'foo_bar'
+      tmp_path "foo_bar"
     end
 
     def tmp_path(*args)
@@ -18,7 +18,7 @@ module RailtiesTests
     end
 
     def engine_path
-      tmp_path('foo_bar')
+      tmp_path("foo_bar")
     end
 
     def bundled_rails(cmd)
@@ -39,7 +39,7 @@ module RailtiesTests
 
       Dir.chdir(engine_path) do
         File.open("Gemfile", "w") do |f|
-          f.write <<-GEMFILE.gsub(/^ {12}/, '')
+          f.write <<-GEMFILE.gsub(/^ {12}/, "")
             source "https://rubygems.org"
 
             gem 'rails', path: '#{RAILS_FRAMEWORK_ROOT}'
diff --git a/railties/test/railties/mounted_engine_test.rb b/railties/test/railties/mounted_engine_test.rb
index 70789d86e2..90439fe778 100644
--- a/railties/test/railties/mounted_engine_test.rb
+++ b/railties/test/railties/mounted_engine_test.rb
@@ -1,8 +1,8 @@
-require 'isolation/abstract_unit'
+require "isolation/abstract_unit"
 
 module ApplicationTests
   class ApplicationRoutingTest < ActiveSupport::TestCase
-     require 'rack/test'
+     require "rack/test"
      include Rack::Test::Methods
      include ActiveSupport::Testing::Isolation
 
@@ -15,7 +15,7 @@ module ApplicationTests
       @plugin = engine "blog"
       @metrics_plugin = engine "metrics"
 
-      app_file 'config/routes.rb', <<-RUBY
+      app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           mount Weblog::Engine, :at => '/', :as => 'weblog'
           resources :posts
@@ -198,7 +198,7 @@ module ApplicationTests
       assert_equal "/john/blog/posts/1", last_response.body
 
       # test generating engine's route from engine with default_url_options
-      get "/john/blog/posts", {}, 'SCRIPT_NAME' => "/foo"
+      get "/john/blog/posts", {}, "SCRIPT_NAME" => "/foo"
       assert_equal "/foo/john/blog/posts/1", last_response.body
 
       # test generating engine's route from application
@@ -212,10 +212,10 @@ module ApplicationTests
       assert_equal "/john/blog/posts", last_response.body
 
       # test generating engine's route from application with default_url_options
-      get "/engine_route", {}, 'SCRIPT_NAME' => "/foo"
+      get "/engine_route", {}, "SCRIPT_NAME" => "/foo"
       assert_equal "/foo/anonymous/blog/posts", last_response.body
 
-      get "/url_for_engine_route", {}, 'SCRIPT_NAME' => "/foo"
+      get "/url_for_engine_route", {}, "SCRIPT_NAME" => "/foo"
       assert_equal "/foo/john/blog/posts", last_response.body
 
       # test generating application's route from engine
@@ -227,21 +227,21 @@ module ApplicationTests
 
       # test generating engine's route from other engine
       get "/metrics/generate_blog_route"
-      assert_equal '/anonymous/blog/posts/1', last_response.body
+      assert_equal "/anonymous/blog/posts/1", last_response.body
 
       get "/metrics/generate_blog_route_in_view"
-      assert_equal '/anonymous/blog/posts/1', last_response.body
+      assert_equal "/anonymous/blog/posts/1", last_response.body
 
       # test generating engine's route from other engine with default_url_options
-      get "/metrics/generate_blog_route", {}, 'SCRIPT_NAME' => '/foo'
-      assert_equal '/foo/anonymous/blog/posts/1', last_response.body
+      get "/metrics/generate_blog_route", {}, "SCRIPT_NAME" => "/foo"
+      assert_equal "/foo/anonymous/blog/posts/1", last_response.body
 
-      get "/metrics/generate_blog_route_in_view", {}, 'SCRIPT_NAME' => '/foo'
-      assert_equal '/foo/anonymous/blog/posts/1', last_response.body
+      get "/metrics/generate_blog_route_in_view", {}, "SCRIPT_NAME" => "/foo"
+      assert_equal "/foo/anonymous/blog/posts/1", last_response.body
 
 
       # test generating application's route from engine with default_url_options
-      get "/someone/blog/generate_application_route", {}, 'SCRIPT_NAME' => '/foo'
+      get "/someone/blog/generate_application_route", {}, "SCRIPT_NAME" => "/foo"
       assert_equal "/foo/", last_response.body
 
       # test polymorphic routes
diff --git a/railties/test/railties/railtie_test.rb b/railties/test/railties/railtie_test.rb
index 4ae6d8fa04..994019267c 100644
--- a/railties/test/railties/railtie_test.rb
+++ b/railties/test/railties/railtie_test.rb
@@ -99,9 +99,9 @@ module RailtiesTest
       require "#{app_path}/config/environment"
 
       assert !$ran_block
-      require 'rake'
-      require 'rake/testtask'
-      require 'rdoc/task'
+      require "rake"
+      require "rake/testtask"
+      require "rdoc/task"
 
       Rails.application.load_tasks
       assert $ran_block
@@ -123,9 +123,9 @@ module RailtiesTest
       require "#{app_path}/config/environment"
 
       assert_equal [], $ran_block
-      require 'rake'
-      require 'rake/testtask'
-      require 'rdoc/task'
+      require "rake"
+      require "rake/testtask"
+      require "rdoc/task"
 
       Rails.application.load_tasks
       assert $ran_block.include?("my_tie")
@@ -196,8 +196,8 @@ module RailtiesTest
     test "we can change our environment if we want to" do
       begin
         original_env = Rails.env
-        Rails.env = 'foo'
-        assert_equal('foo', Rails.env)
+        Rails.env = "foo"
+        assert_equal("foo", Rails.env)
       ensure
         Rails.env = original_env
         assert_equal(original_env, Rails.env)
diff --git a/railties/test/test_unit/reporter_test.rb b/railties/test/test_unit/reporter_test.rb
index 0d64b48550..875bc954eb 100644
--- a/railties/test/test_unit/reporter_test.rb
+++ b/railties/test/test_unit/reporter_test.rb
@@ -1,6 +1,6 @@
-require 'abstract_unit'
-require 'rails/test_unit/reporter'
-require 'minitest/mock'
+require "abstract_unit"
+require "rails/test_unit/reporter"
+require "minitest/mock"
 
 class TestUnitReporterTest < ActiveSupport::TestCase
   class ExampleTest < Minitest::Test
@@ -33,7 +33,7 @@ class TestUnitReporterTest < ActiveSupport::TestCase
     @reporter.record(passing_test)
     @reporter.record(skipped_test)
     @reporter.report
-    assert_no_match 'Failed tests:', @output.string
+    assert_no_match "Failed tests:", @output.string
     assert_rerun_snippet_count 0
   end
 
@@ -87,7 +87,7 @@ class TestUnitReporterTest < ActiveSupport::TestCase
     @reporter.record(failed_test)
     @reporter.report
 
-    assert_no_match 'Failed tests:', @output.string
+    assert_no_match "Failed tests:", @output.string
   end
 
   test "fail fast interrupts run on failure" do
@@ -100,7 +100,7 @@ class TestUnitReporterTest < ActiveSupport::TestCase
     rescue Interrupt
       interrupt_raised = true
     ensure
-      assert interrupt_raised, 'Expected Interrupt to be raised.'
+      assert interrupt_raised, "Expected Interrupt to be raised."
     end
   end
 
@@ -114,7 +114,7 @@ class TestUnitReporterTest < ActiveSupport::TestCase
     rescue Interrupt
       interrupt_raised = true
     ensure
-      assert interrupt_raised, 'Expected Interrupt to be raised.'
+      assert interrupt_raised, "Expected Interrupt to be raised."
     end
   end
 
@@ -122,7 +122,7 @@ class TestUnitReporterTest < ActiveSupport::TestCase
     fail_fast = Rails::TestUnitReporter.new @output, fail_fast: true
 
     fail_fast.record(skipped_test)
-    assert_no_match 'Failed tests:', @output.string
+    assert_no_match "Failed tests:", @output.string
   end
 
   test "outputs colored passing results" do
diff --git a/railties/test/version_test.rb b/railties/test/version_test.rb
index f270d8f0c9..86a482e091 100644
--- a/railties/test/version_test.rb
+++ b/railties/test/version_test.rb
@@ -1,4 +1,4 @@
-require 'abstract_unit'
+require "abstract_unit"
 
 class VersionTest < ActiveSupport::TestCase
   def test_rails_version_returns_a_string