13 files changed, 56 insertions, 41 deletions
diff --git a/guides/source/3_0_release_notes.md b/guides/source/3_0_release_notes.md
index e793146c2c..e936644daf 100644
--- a/guides/source/3_0_release_notes.md
+++ b/guides/source/3_0_release_notes.md
@@ -38,7 +38,7 @@ If you're upgrading an existing application, it's a great idea to have good test
 
 Rails 3.0 requires Ruby 1.8.7 or higher. Support for all of the previous Ruby versions has been dropped officially and you should upgrade as early as possible. Rails 3.0 is also compatible with Ruby 1.9.2.
 
-TIP: Note that Ruby 1.8.7 p248 and p249 have marshaling bugs that crash Rails 3.0. Ruby Enterprise Edition have these fixed since release 1.8.7-2010.02 though. On the 1.9 front, Ruby 1.9.1 is not usable because it outright segfaults on Rails 3.0, so if you want to use Rails 3 with 1.9.x jump on 1.9.2 for smooth sailing.
+TIP: Note that Ruby 1.8.7 p248 and p249 have marshalling bugs that crash Rails 3.0. Ruby Enterprise Edition have these fixed since release 1.8.7-2010.02 though. On the 1.9 front, Ruby 1.9.1 is not usable because it outright segfaults on Rails 3.0, so if you want to use Rails 3 with 1.9.x jump on 1.9.2 for smooth sailing.
 
 ### Rails Application object
 
diff --git a/guides/source/3_1_release_notes.md b/guides/source/3_1_release_notes.md
index 8c3dc3454d..d6981656ee 100644
--- a/guides/source/3_1_release_notes.md
+++ b/guides/source/3_1_release_notes.md
@@ -26,7 +26,7 @@ If you're upgrading an existing application, it's a great idea to have good test
 
 Rails 3.1 requires Ruby 1.8.7 or higher. Support for all of the previous Ruby versions has been dropped officially and you should upgrade as early as possible. Rails 3.1 is also compatible with Ruby 1.9.2.
 
-TIP: Note that Ruby 1.8.7 p248 and p249 have marshaling bugs that crash Rails. Ruby Enterprise Edition have these fixed since release 1.8.7-2010.02 though. On the 1.9 front, Ruby 1.9.1 is not usable because it outright segfaults, so if you want to use 1.9.x jump on 1.9.2 for smooth sailing.
+TIP: Note that Ruby 1.8.7 p248 and p249 have marshalling bugs that crash Rails. Ruby Enterprise Edition have these fixed since release 1.8.7-2010.02 though. On the 1.9 front, Ruby 1.9.1 is not usable because it outright segfaults, so if you want to use 1.9.x jump on 1.9.2 for smooth sailing.
 
 ### What to update in your apps
 
diff --git a/guides/source/4_2_release_notes.md b/guides/source/4_2_release_notes.md
index f7c40d19e9..51d06bd07d 100644
--- a/guides/source/4_2_release_notes.md
+++ b/guides/source/4_2_release_notes.md
@@ -44,7 +44,7 @@ to their respective adapters. Active Job comes pre-configured with an inline
 runner that executes jobs right away.
 
 Jobs often need to take Active Record objects as arguments. Active Job passes
-object references as URIs (uniform resource identifiers) instead of marshaling
+object references as URIs (uniform resource identifiers) instead of marshalling
 the object itself. The new [Global ID](https://github.com/rails/globalid)
 library builds URIs and looks up the objects they reference. Passing Active
 Record objects as job arguments just works by using Global ID internally.
diff --git a/guides/source/active_storage_overview.md b/guides/source/active_storage_overview.md
index 71ba6184e0..d5387219f5 100644
--- a/guides/source/active_storage_overview.md
+++ b/guides/source/active_storage_overview.md
@@ -82,6 +82,14 @@ To use the Amazon S3 service in production, you add the following to
 config.active_storage.service = :amazon
 ```
 
+To use the test service when testing, you add the following to
+`config/environments/test.rb`:
+
+```ruby
+# Store uploaded files on the local file system in a temporary directory.
+config.active_storage.service = :test
+```
+
 Continue reading for more information on the built-in service adapters (e.g.
 `Disk` and `S3`) and the configuration they require.
 
diff --git a/guides/source/active_support_core_extensions.md b/guides/source/active_support_core_extensions.md
index f9fc7044ba..6b0554bb5f 100644
--- a/guides/source/active_support_core_extensions.md
+++ b/guides/source/active_support_core_extensions.md
@@ -590,9 +590,9 @@ NOTE: Defined in `active_support/core_ext/module/attribute_accessors.rb`.
 
 ### Parents
 
-#### `parent`
+#### `module_parent`
 
-The `parent` method on a nested named module returns the module that contains its corresponding constant:
+The `module_parent` method on a nested named module returns the module that contains its corresponding constant:
 
 ```ruby
 module X
@@ -603,19 +603,19 @@ module X
 end
 M = X::Y::Z
 
-X::Y::Z.parent # => X::Y
-M.parent       # => X::Y
+X::Y::Z.module_parent # => X::Y
+M.module_parent       # => X::Y
 ```
 
-If the module is anonymous or belongs to the top-level, `parent` returns `Object`.
+If the module is anonymous or belongs to the top-level, `module_parent` returns `Object`.
 
-WARNING: Note that in that case `parent_name` returns `nil`.
+WARNING: Note that in that case `module_parent_name` returns `nil`.
 
 NOTE: Defined in `active_support/core_ext/module/introspection.rb`.
 
-#### `parent_name`
+#### `module_parent_name`
 
-The `parent_name` method on a nested named module returns the fully qualified name of the module that contains its corresponding constant:
+The `module_parent_name` method on a nested named module returns the fully qualified name of the module that contains its corresponding constant:
 
 ```ruby
 module X
@@ -626,19 +626,19 @@ module X
 end
 M = X::Y::Z
 
-X::Y::Z.parent_name # => "X::Y"
-M.parent_name       # => "X::Y"
+X::Y::Z.module_parent_name # => "X::Y"
+M.module_parent_name       # => "X::Y"
 ```
 
-For top-level or anonymous modules `parent_name` returns `nil`.
+For top-level or anonymous modules `module_parent_name` returns `nil`.
 
-WARNING: Note that in that case `parent` returns `Object`.
+WARNING: Note that in that case `module_parent` returns `Object`.
 
 NOTE: Defined in `active_support/core_ext/module/introspection.rb`.
 
-#### `parents`
+#### `module_parents`
 
-The method `parents` calls `parent` on the receiver and upwards until `Object` is reached. The chain is returned in an array, from bottom to top:
+The method `module_parents` calls `module_parent` on the receiver and upwards until `Object` is reached. The chain is returned in an array, from bottom to top:
 
 ```ruby
 module X
@@ -649,8 +649,8 @@ module X
 end
 M = X::Y::Z
 
-X::Y::Z.parents # => [X::Y, X, Object]
-M.parents       # => [X::Y, X, Object]
+X::Y::Z.module_parents # => [X::Y, X, Object]
+M.module_parents       # => [X::Y, X, Object]
 ```
 
 NOTE: Defined in `active_support/core_ext/module/introspection.rb`.
diff --git a/guides/source/asset_pipeline.md b/guides/source/asset_pipeline.md
index bf046a3341..66cf9da33b 100644
--- a/guides/source/asset_pipeline.md
+++ b/guides/source/asset_pipeline.md
@@ -184,9 +184,8 @@ the file `scaffolds.css` (or `scaffolds.scss` if `sass-rails` is in the
 `Gemfile`.)
 
 For example, if you generate a `ProjectsController`, Rails will also add a new
-file at `app/assets/javascripts/projects.coffee` and another at
-`app/assets/stylesheets/projects.scss`. By default these files will be ready
-to use by your application immediately using the `require_tree` directive. See
+file at `app/assets/stylesheets/projects.scss`. By default these files will be
+ready to use by your application immediately using the `require_tree` directive. See
 [Manifest Files and Directives](#manifest-files-and-directives) for more details
 on require_tree.
 
diff --git a/guides/source/command_line.md b/guides/source/command_line.md
index 7fa0a49203..5fd3ad17de 100644
--- a/guides/source/command_line.md
+++ b/guides/source/command_line.md
@@ -185,7 +185,7 @@ The controller generator is expecting parameters in the form of `generate contro
 ```bash
 $ rails generate controller Greetings hello
      create  app/controllers/greetings_controller.rb
-      route  get "greetings/hello"
+      route  get 'greetings/hello'
      invoke  erb
      create    app/views/greetings
      create    app/views/greetings/hello.html.erb
@@ -193,9 +193,8 @@ $ rails generate controller Greetings hello
      create    test/controllers/greetings_controller_test.rb
      invoke  helper
      create    app/helpers/greetings_helper.rb
+     invoke    test_unit
      invoke  assets
-     invoke    coffee
-     create      app/assets/javascripts/greetings.coffee
      invoke    scss
      create      app/assets/stylesheets/greetings.scss
 ```
diff --git a/guides/source/configuring.md b/guides/source/configuring.md
index 18a377a02e..812565b207 100644
--- a/guides/source/configuring.md
+++ b/guides/source/configuring.md
@@ -119,12 +119,11 @@ defaults to `:debug` for all environments. The available log levels are: `:debug
 * `config.logger` is the logger that will be used for `Rails.logger` and any related Rails logging such as `ActiveRecord::Base.logger`. It defaults to an instance of `ActiveSupport::TaggedLogging` that wraps an instance of `ActiveSupport::Logger` which outputs a log to the `log/` directory. You can supply a custom logger, to get full compatibility you must follow these guidelines:
   * To support a formatter, you must manually assign a formatter from the `config.log_formatter` value to the logger.
   * To support tagged logs, the log instance must be wrapped with `ActiveSupport::TaggedLogging`.
-  * To support silencing, the logger must include `LoggerSilence` and `ActiveSupport::LoggerThreadSafeLevel` modules. The `ActiveSupport::Logger` class already includes these modules.
+  * To support silencing, the logger must include `ActiveSupport::LoggerSilence`  module. The `ActiveSupport::Logger` class already includes these modules.
 
     ```ruby
     class MyLogger < ::Logger
-      include ActiveSupport::LoggerThreadSafeLevel
-      include LoggerSilence
+      include ActiveSupport::LoggerSilence
     end
 
     mylogger           = MyLogger.new(STDOUT)
diff --git a/guides/source/contributing_to_ruby_on_rails.md b/guides/source/contributing_to_ruby_on_rails.md
index 01848bdc11..1beadd78d6 100644
--- a/guides/source/contributing_to_ruby_on_rails.md
+++ b/guides/source/contributing_to_ruby_on_rails.md
@@ -336,6 +336,26 @@ $ bundle exec ruby -w -Itest test/mail_layout_test.rb -n test_explicit_class_lay
 The `-n` option allows you to run a single method instead of the whole
 file.
 
+#### Running tests with a specific seed
+
+Test execution is randomized with a randomization seed. If you are experiencing random
+test failures you can more accurately reproduce a failing test scenario by specifically
+setting the randomization seed.
+
+Running all tests for a component:
+
+```bash
+$ cd actionmailer
+$ SEED=15002 bundle exec rake test
+```
+
+Running a single test file:
+
+```bash
+$ cd actionmailer
+$ SEED=15002 bundle exec ruby -w -Itest test/mail_layout_test.rb
+```
+
 #### Testing Active Record
 
 First, create the databases you'll need. You can find a list of the required
diff --git a/guides/source/generators.md b/guides/source/generators.md
index 89424a161b..f028d14998 100644
--- a/guides/source/generators.md
+++ b/guides/source/generators.md
@@ -203,8 +203,6 @@ $ rails generate scaffold User name:string
       create    test/application_system_test_case.rb
       create    test/system/users_test.rb
       invoke  assets
-      invoke    coffee
-      create      app/assets/javascripts/users.coffee
       invoke    scss
       create      app/assets/stylesheets/users.scss
       invoke  scss
@@ -426,9 +424,8 @@ $ rails generate scaffold Comment body:text
       create    test/application_system_test_case.rb
       create    test/system/comments_test.rb
       invoke  assets
-      invoke    coffee
-      create      app/assets/javascripts/comments.coffee
       invoke    scss
+      create    app/assets/stylesheets/scaffolds.scss
 ```
 
 Fallbacks allow your generators to have a single responsibility, increasing code reuse and reducing the amount of duplication.
diff --git a/guides/source/getting_started.md b/guides/source/getting_started.md
index 197a198db7..e2f558d74c 100644
--- a/guides/source/getting_started.md
+++ b/guides/source/getting_started.md
@@ -126,7 +126,7 @@ run the following:
 $ rails --version
 ```
 
-If it says something like "Rails 5.1.1", you are ready to continue.
+If it says something like "Rails 5.2.1", you are ready to continue.
 
 ### Creating the Blog Application
 
@@ -272,8 +272,6 @@ invoke  helper
 create    app/helpers/welcome_helper.rb
 invoke    test_unit
 invoke  assets
-invoke    coffee
-create      app/assets/javascripts/welcome.coffee
 invoke    scss
 create      app/assets/stylesheets/welcome.scss
 ```
@@ -1665,7 +1663,6 @@ This creates five files and one empty directory:
 | app/views/comments/                          | Views of the controller are stored here  |
 | test/controllers/comments_controller_test.rb | The test for the controller              |
 | app/helpers/comments_helper.rb               | A view helper file                       |
-| app/assets/javascripts/comments.coffee       | CoffeeScript for the controller          |
 | app/assets/stylesheets/comments.scss         | Cascading style sheet for the controller |
 
 Like with any blog, our readers will create their comments directly after
diff --git a/guides/source/upgrading_ruby_on_rails.md b/guides/source/upgrading_ruby_on_rails.md
index befd4e08c0..a0553c1ccc 100644
--- a/guides/source/upgrading_ruby_on_rails.md
+++ b/guides/source/upgrading_ruby_on_rails.md
@@ -41,7 +41,7 @@ Rails generally stays close to the latest released Ruby version when it's releas
 * Rails 3.2.x is the last branch to support Ruby 1.8.7.
 * Rails 3 and above require Ruby 1.8.7 or higher. Support for all of the previous Ruby versions has been dropped officially. You should upgrade as early as possible.
 
-TIP: Ruby 1.8.7 p248 and p249 have marshaling bugs that crash Rails. Ruby Enterprise Edition has these fixed since the release of 1.8.7-2010.02. On the 1.9 front, Ruby 1.9.1 is not usable because it outright segfaults, so if you want to use 1.9.x, jump straight to 1.9.3 for smooth sailing.
+TIP: Ruby 1.8.7 p248 and p249 have marshalling bugs that crash Rails. Ruby Enterprise Edition has these fixed since the release of 1.8.7-2010.02. On the 1.9 front, Ruby 1.9.1 is not usable because it outright segfaults, so if you want to use 1.9.x, jump straight to 1.9.3 for smooth sailing.
 
 ### The Update Task
 
diff --git a/guides/source/working_with_javascript_in_rails.md b/guides/source/working_with_javascript_in_rails.md
index 36f5039883..c36b3faa6c 100644
--- a/guides/source/working_with_javascript_in_rails.md
+++ b/guides/source/working_with_javascript_in_rails.md
@@ -494,10 +494,6 @@ replace the entire `<body>` of the page with the `<body>` of the response. It
 will then use PushState to change the URL to the correct one, preserving
 refresh semantics and giving you pretty URLs.
 
-The only thing you have to do to enable Turbolinks is have it in your `Gemfile`,
-and put `//= require turbolinks` in your JavaScript manifest, which is usually
-`app/assets/javascripts/application.js`.
-
 If you want to disable Turbolinks for certain links, add a `data-turbolinks="false"`
 attribute to the tag: