This commit merges most of the work done by Piotr Sarnacki in his Ruby Summer of Code project.

His work brings several capabilities from app to engines, as routes, middleware stack, asset handling and much more. Please check Rails::Engine documentation for more refenrences.

Merge remote branch 'drogus/engines'

4 files changed, 28 insertions, 56 deletions

diff --git a/railties/lib/rails/application/bootstrap.rb b/railties/lib/rails/application/bootstrap.rb
index 44e26b5713..e39b3bc705 100644
--- a/railties/lib/rails/application/bootstrap.rb
+++ b/railties/lib/rails/application/bootstrap.rb
@@ -6,10 +6,7 @@ module Rails
     module Bootstrap
       include Initializable
 
-      initializer :load_environment_config do
-        environment = config.paths.config.environments.to_a.first
-        require environment if environment
-      end
+      initializer :load_environment_hook do end
 
       initializer :load_active_support do
         require 'active_support/dependencies'
@@ -73,4 +70,4 @@ module Rails
       end
     end
   end
-end
\ No newline at end of file
+end
diff --git a/railties/lib/rails/application/configurable.rb b/railties/lib/rails/application/configurable.rb
deleted file mode 100644
index f598e33965..0000000000
--- a/railties/lib/rails/application/configurable.rb
+++ /dev/null
@@ -1,19 +0,0 @@
-module Rails
-  class Application
-    module Configurable
-      def self.included(base)
-        base.extend ClassMethods
-      end
-
-      module ClassMethods
-        def inherited(base)
-          raise "You cannot inherit from a Rails::Application child"
-        end
-      end
-
-      def config
-        @config ||= Application::Configuration.new(self.class.find_root_with_flag("config.ru", Dir.pwd))
-      end
-    end
-  end
-end
\ No newline at end of file
diff --git a/railties/lib/rails/application/configuration.rb b/railties/lib/rails/application/configuration.rb
index c3418e0d80..477bbbc1e7 100644
--- a/railties/lib/rails/application/configuration.rb
+++ b/railties/lib/rails/application/configuration.rb
@@ -1,16 +1,13 @@
-require 'active_support/deprecation'
 require 'active_support/core_ext/string/encoding'
 require 'rails/engine/configuration'
 
 module Rails
   class Application
     class Configuration < ::Rails::Engine::Configuration
-      include ::Rails::Configuration::Deprecated
-
       attr_accessor :allow_concurrency, :cache_classes, :cache_store,
                     :encoding, :consider_all_requests_local, :dependency_loading,
-                    :filter_parameters,  :log_level, :logger, :middleware,
-                    :plugins, :preload_frameworks, :reload_plugins,
+                    :filter_parameters,  :log_level, :logger,
+                    :preload_frameworks, :reload_plugins,
                     :secret_token, :serve_static_assets, :session_options,
                     :time_zone, :whiny_nils
 
@@ -28,6 +25,22 @@ module Rails
         @middleware = app_middleware
       end
 
+      def asset_path=(value)
+        action_mailer.asset_path = value if respond_to?(:action_mailer) && action_mailer
+        action_controller.asset_path = value if respond_to?(:action_controller) && action_controller
+        super(value)
+      end
+
+      def asset_host=(value)
+        action_mailer.asset_host = value if action_mailer
+        action_controller.asset_host = value if action_controller
+        super(value)
+      end
+
+      def compiled_asset_path
+        "/"
+      end
+
       def encoding=(value)
         @encoding = value
         if "ruby".encoding_aware?
@@ -48,19 +61,10 @@ module Rails
           paths.app.controllers << builtin_controller if builtin_controller
           paths.config.database     "config/database.yml"
           paths.config.environment  "config/environment.rb"
-          paths.config.environments "config/environments", :glob => "#{Rails.env}.rb"
           paths.lib.templates       "lib/templates"
           paths.log                 "log/#{Rails.env}.log"
           paths.tmp                 "tmp"
           paths.tmp.cache           "tmp/cache"
-          paths.vendor              "vendor", :load_path => true
-          paths.vendor.plugins      "vendor/plugins"
-
-          if File.exists?("#{root}/test/mocks/#{Rails.env}")
-            ActiveSupport::Deprecation.warn "\"Rails.root/test/mocks/#{Rails.env}\" won't be added " <<
-              "automatically to load paths anymore in future releases"
-            paths.mocks_path  "test/mocks", :autoload => true, :glob => Rails.env
-          end
 
           paths
         end
diff --git a/railties/lib/rails/application/railties.rb b/railties/lib/rails/application/railties.rb
index b3e6693f89..c1d2de571f 100644
--- a/railties/lib/rails/application/railties.rb
+++ b/railties/lib/rails/application/railties.rb
@@ -1,31 +1,21 @@
-module Rails
-  class Application
-    class Railties
-      # TODO Write tests for this behavior extracted from Application
-      def initialize(config)
-        @config = config
-      end
+require 'rails/engine/railties'
 
+module Rails
+  class Application < Engine
+    class Railties < Rails::Engine::Railties
       def all(&block)
-        @all ||= railties + engines + plugins
+        @all ||= railties + engines + super
         @all.each(&block) if block
         @all
       end
 
       def railties
-        @railties ||= ::Rails::Railtie.subclasses.map(&:new)
+        @railties ||= ::Rails::Railtie.subclasses.map(&:instance)
       end
 
       def engines
-        @engines ||= ::Rails::Engine.subclasses.map(&:new)
-      end
-
-      def plugins
-        @plugins ||= begin
-          plugin_names = (@config.plugins || [:all]).map { |p| p.to_sym }
-          Plugin.all(plugin_names, @config.paths.vendor.plugins)
-        end
+        @engines ||= ::Rails::Engine.subclasses.map(&:instance)
       end
     end
   end
-end
\ No newline at end of file
+end