depend_on_asset is not required anymore on sprockets-rails 2.1.2

Gemfile

@@ -11,6 +11,7 @@ gem 'rack-cache', '~> 1.2'
 gem 'jquery-rails', '~> 3.1.0'
 gem 'turbolinks'
 gem 'coffee-rails', '~> 4.0.0'
+gem 'sprockets-rails', github: 'rails/sprockets-rails', branch: '2-1-stable'
 
 # require: false so bcrypt is loaded only when has_secure_password is used.
 # This is to avoid ActiveModel (and by extension the entire framework)

guides/source/asset_pipeline.md

@@ -581,23 +581,8 @@ runtime. To disable this behavior you can set:
 config.assets.raise_runtime_errors = false
 ```
 
-When `raise_runtime_errors` is set to `false` sprockets will not check that dependencies of assets are declared properly. Here is a scenario where you must tell the asset pipeline about a dependency:
-
-If you have `application.css.erb` that references `logo.png` like this:
-
-```css
-#logo { background: url(<%= asset_data_uri 'logo.png' %>) }
-```
-
-Then you must declare that `logo.png` is a dependency of `application.css.erb`, so when the image gets re-compiled, the css file does as well. You can do this using the `//= depend_on_asset` declaration:
-
-```css
-//= depend_on_asset "logo.png"
-#logo { background: url(<%= asset_data_uri 'logo.png' %>) }
-```
-
-Without this declaration you may experience strange behavior when pushing to production that is difficult to debug. When you have `raise_runtime_errors` set to `true`, dependencies will be checked at runtime so you can ensure that all dependencies are met.
-
+When this option is true asset pipeline will check if all the assets loaded in your application
+are included in the `config.assets.precompile` list.
 
 ### Turning Debugging Off
 
@@ -943,7 +928,7 @@ gem.
 ```ruby
 config.assets.css_compressor = :yui
 ```
-The other option for compressing CSS if you have the sass-rails gem installed is 
+The other option for compressing CSS if you have the sass-rails gem installed is
 
 ```ruby
 config.assets.css_compressor = :sass
@@ -1018,7 +1003,7 @@ The X-Sendfile header is a directive to the web server to ignore the response
 from the application, and instead serve a specified file from disk. This option
 is off by default, but can be enabled if your server supports it. When enabled,
 this passes responsibility for serving the file to the web server, which is
-faster. Have a look at [send_file](http://api.rubyonrails.org/classes/ActionController/DataStreaming.html#method-i-send_file) 
+faster. Have a look at [send_file](http://api.rubyonrails.org/classes/ActionController/DataStreaming.html#method-i-send_file)
 on how to use this feature.
 
 Apache and nginx support this option, which can be enabled in

railties/test/application/assets_test.rb

@@ -42,7 +42,7 @@ def assert_no_file_exists(filename)
 
     test "assets routes have higher priority" do
       app_file "app/assets/images/rails.png", "notactuallyapng"
-      app_file "app/assets/javascripts/demo.js.erb", "//= depend_on_asset 'rails.png'\na = <%= image_path('rails.png').inspect %>;"
+      app_file "app/assets/javascripts/demo.js.erb", "a = <%= image_path('rails.png').inspect %>;"
 
       app_file 'config/routes.rb', <<-RUBY
         Rails.application.routes.draw do
@@ -200,7 +200,7 @@ class User < ActiveRecord::Base; raise 'should not be reached'; end
 
     test "precompile creates a manifest file with all the assets listed" do
       app_file "app/assets/images/rails.png", "notactuallyapng"
-      app_file "app/assets/stylesheets/application.css.erb", "//= depend_on_asset 'rails.png'\n <%= asset_path('rails.png') %>"
+      app_file "app/assets/stylesheets/application.css.erb", "<%= asset_path('rails.png') %>"
       app_file "app/assets/javascripts/application.js", "alert();"
       # digest is default in false, we must enable it for test environment
       add_to_config "config.assets.digest = true"
@@ -261,7 +261,7 @@ class User < ActiveRecord::Base; raise 'should not be reached'; end
     test "precompile shouldn't use the digests present in manifest.json" do
       app_file "app/assets/images/rails.png", "notactuallyapng"
 
-      app_file "app/assets/stylesheets/application.css.erb", "//= depend_on rails.png\np { url: <%= asset_path('rails.png') %> }"
+      app_file "app/assets/stylesheets/application.css.erb", "p { url: <%= asset_path('rails.png') %> }"
 
       ENV["RAILS_ENV"] = "production"
       precompile!
@@ -280,7 +280,7 @@ class User < ActiveRecord::Base; raise 'should not be reached'; end
 
     test "precompile appends the md5 hash to files referenced with asset_path and run in production with digest true" do
       app_file "app/assets/images/rails.png", "notactuallyapng"
-      app_file "app/assets/stylesheets/application.css.erb", "//= depend_on_asset 'rails.png'\n<%= asset_path('rails.png') %>"
+      app_file "app/assets/stylesheets/application.css.erb", "<%= asset_path('rails.png') %>"
       add_to_config "config.assets.compile = true"
       add_to_config "config.assets.digest = true"
 
@@ -449,7 +449,7 @@ class ::PostsController < ActionController::Base; end
 
     test "asset urls should be protocol-relative if no request is in scope" do
       app_file "app/assets/images/rails.png", "notreallyapng"
-      app_file "app/assets/javascripts/image_loader.js.erb", "//= depend_on_asset 'rails.png'\n\nvar src='<%= image_path('rails.png') %>';"
+      app_file "app/assets/javascripts/image_loader.js.erb", "var src='<%= image_path('rails.png') %>';"
       add_to_config "config.assets.precompile = %w{image_loader.js}"
       add_to_config "config.asset_host = 'example.com'"
       precompile!
@@ -461,7 +461,7 @@ class ::PostsController < ActionController::Base; end
       ENV["RAILS_RELATIVE_URL_ROOT"] = "/sub/uri"
       app_file "app/assets/images/rails.png", "notreallyapng"
 
-      app_file "app/assets/javascripts/app.js.erb", "//= depend_on_asset 'rails.png'\n\nvar src='<%= image_path('rails.png') %>';"
+      app_file "app/assets/javascripts/app.js.erb", "var src='<%= image_path('rails.png') %>';"
       add_to_config "config.assets.precompile = %w{app.js}"
       precompile!