Removed superfluous 'tracks' directory at the root of the repository.

Testing commits to github.

vendor/rails/actionpack/lib/action_controller/components.rb

@@ -0,0 +1,165 @@
+module ActionController #:nodoc:
+  # Components allow you to call other actions for their rendered response while executing another action. You can either delegate
+  # the entire response rendering or you can mix a partial response in with your other content.
+  #
+  #   class WeblogController < ActionController::Base
+  #     # Performs a method and then lets hello_world output its render
+  #     def delegate_action
+  #       do_other_stuff_before_hello_world
+  #       render_component :controller => "greeter",  :action => "hello_world", :params => { :person => "david" }
+  #     end
+  #   end
+  #
+  #   class GreeterController < ActionController::Base
+  #     def hello_world
+  #       render :text => "#{params[:person]} says, Hello World!"
+  #     end
+  #   end
+  #
+  # The same can be done in a view to do a partial rendering:
+  #
+  #   Let's see a greeting:
+  #   <%= render_component :controller => "greeter", :action => "hello_world" %>
+  #
+  # It is also possible to specify the controller as a class constant, bypassing the inflector
+  # code to compute the controller class at runtime:
+  #
+  # <%= render_component :controller => GreeterController, :action => "hello_world" %>
+  #
+  # == When to use components
+  #
+  # Components should be used with care. They're significantly slower than simply splitting reusable parts into partials and
+  # conceptually more complicated. Don't use components as a way of separating concerns inside a single application. Instead,
+  # reserve components to those rare cases where you truly have reusable view and controller elements that can be employed
+  # across many applications at once.
+  #
+  # So to repeat: Components are a special-purpose approach that can often be replaced with better use of partials and filters.
+  module Components
+    def self.included(base) #:nodoc:
+      base.class_eval do
+        include InstanceMethods
+        extend ClassMethods
+
+        helper do
+          def render_component(options)
+            @controller.send!(:render_component_as_string, options)
+          end
+        end
+
+        # If this controller was instantiated to process a component request,
+        # +parent_controller+ points to the instantiator of this controller.
+        attr_accessor :parent_controller
+
+        alias_method_chain :process_cleanup, :components
+        alias_method_chain :set_session_options, :components
+        alias_method_chain :flash, :components
+
+        alias_method :component_request?, :parent_controller
+      end
+    end
+
+    module ClassMethods
+      # Track parent controller to identify component requests
+      def process_with_components(request, response, parent_controller = nil) #:nodoc:
+        controller = new
+        controller.parent_controller = parent_controller
+        controller.process(request, response)
+      end
+    end
+
+    module InstanceMethods
+      # Extracts the action_name from the request parameters and performs that action.
+      def process_with_components(request, response, method = :perform_action, *arguments) #:nodoc:
+        flash.discard if component_request?
+        process_without_components(request, response, method, *arguments)
+      end
+
+      protected
+        # Renders the component specified as the response for the current method
+        def render_component(options) #:doc:
+          component_logging(options) do
+            render_for_text(component_response(options, true).body, response.headers["Status"])
+          end
+        end
+
+        # Returns the component response as a string
+        def render_component_as_string(options) #:doc:
+          component_logging(options) do
+            response = component_response(options, false)
+
+            if redirected = response.redirected_to
+              render_component_as_string(redirected)
+            else
+              response.body
+            end
+          end
+        end
+
+        def flash_with_components(refresh = false) #:nodoc:
+          if !defined?(@_flash) || refresh
+            @_flash =
+              if defined?(@parent_controller)
+                @parent_controller.flash
+              else
+                flash_without_components
+              end
+          end
+          @_flash
+        end
+
+      private
+        def component_response(options, reuse_response)
+          klass    = component_class(options)
+          request  = request_for_component(klass.controller_name, options)
+          new_response = reuse_response ? response : response.dup
+
+          klass.process_with_components(request, new_response, self)
+        end
+
+        # determine the controller class for the component request
+        def component_class(options)
+          if controller = options[:controller]
+            controller.is_a?(Class) ? controller : "#{controller.camelize}Controller".constantize
+          else
+            self.class
+          end
+        end
+
+        # Create a new request object based on the current request.
+        # The new request inherits the session from the current request,
+        # bypassing any session options set for the component controller's class
+        def request_for_component(controller_name, options)
+          new_request         = request.dup
+          new_request.session = request.session
+
+          new_request.instance_variable_set(
+            :@parameters,
+            (options[:params] || {}).with_indifferent_access.update(
+              "controller" => controller_name, "action" => options[:action], "id" => options[:id]
+            )
+          )
+
+          new_request
+        end
+
+        def component_logging(options)
+          if logger
+            logger.info "Start rendering component (#{options.inspect}): "
+            result = yield
+            logger.info "\n\nEnd of component rendering"
+            result
+          else
+            yield
+          end
+        end
+
+        def set_session_options_with_components(request)
+          set_session_options_without_components(request) unless component_request?
+        end
+
+        def process_cleanup_with_components
+          process_cleanup_without_components unless component_request?
+        end
+    end
+  end
+end