Merge commit 'mainstream/master'

Conflicts:

	actionmailer/lib/action_mailer/base.rb
	actionpack/lib/action_controller/base.rb
	actionpack/lib/action_controller/mime_type.rb
	railties/doc/guides/html/activerecord_validations_callbacks.html
	railties/doc/guides/html/caching_with_rails.html
	railties/doc/guides/html/command_line.html
	railties/doc/guides/html/configuring.html
	railties/doc/guides/html/creating_plugins.html
	railties/doc/guides/html/finders.html
	railties/doc/guides/html/routing_outside_in.html
	railties/doc/guides/source/activerecord_validations_callbacks.txt
	railties/doc/guides/source/caching_with_rails.txt
	railties/doc/guides/source/command_line.txt
	railties/doc/guides/source/creating_plugins/acts_as_yaffle.txt
	railties/doc/guides/source/creating_plugins/controllers.txt
	railties/doc/guides/source/creating_plugins/core_ext.txt
	railties/doc/guides/source/creating_plugins/helpers.txt
	railties/doc/guides/source/creating_plugins/index.txt
	railties/doc/guides/source/creating_plugins/migration_generator.txt
	railties/doc/guides/source/creating_plugins/models.txt
	railties/doc/guides/source/creating_plugins/odds_and_ends.txt
	railties/doc/guides/source/creating_plugins/routes.txt
	railties/doc/guides/source/finders.txt
	railties/doc/guides/source/routing_outside_in.txt
	railties/doc/guides/source/testing_rails_applications.txt

1 files changed, 44 insertions, 5 deletions

diff --git a/railties/lib/rails/plugin.rb b/railties/lib/rails/plugin.rb
index 4d983843af..4901abe808 100644
--- a/railties/lib/rails/plugin.rb
+++ b/railties/lib/rails/plugin.rb
@@ -28,15 +28,19 @@ module Rails
     end
     
     def valid?
-      File.directory?(directory) && (has_lib_directory? || has_init_file?)
+      File.directory?(directory) && (has_app_directory? || has_lib_directory? || has_init_file?)
     end
   
     # Returns a list of paths this plugin wishes to make available in <tt>$LOAD_PATH</tt>.
     def load_paths
       report_nonexistant_or_empty_plugin! unless valid?
-      has_lib_directory? ? [lib_path] : []
+      
+      returning [] do |load_paths|
+        load_paths << lib_path  if has_lib_directory?
+        load_paths << app_paths if has_app_directory?
+      end.flatten
     end
-
+    
     # Evaluates a plugin's init.rb file.
     def load(initializer)
       return if loaded?
@@ -56,7 +60,31 @@ module Rails
     def about
       @about ||= load_about_information
     end
+
+    # Engines are plugins with an app/ directory.
+    def engine?
+      has_app_directory?
+    end
+    
+    # Returns true if the engine ships with a routing file
+    def routed?
+      File.exist?(routing_file)
+    end
+
+
+    def view_path
+      File.join(directory, 'app', 'views')
+    end
+
+    def controller_path
+      File.join(directory, 'app', 'controllers')
+    end
+
+    def routing_file
+      File.join(directory, 'config', 'routes.rb')
+    end
     
+
     private
       def load_about_information
         about_yml_path = File.join(@directory, "about.yml")
@@ -68,8 +96,13 @@ module Rails
 
       def report_nonexistant_or_empty_plugin!
         raise LoadError, "Can not find the plugin named: #{name}"
-      end      
-    
+      end
+
+      
+      def app_paths
+        [ File.join(directory, 'app', 'models'), File.join(directory, 'app', 'helpers'), controller_path ]
+      end
+      
       def lib_path
         File.join(directory, 'lib')
       end
@@ -86,6 +119,11 @@ module Rails
         File.file?(gem_init_path) ? gem_init_path : classic_init_path
       end
 
+
+      def has_app_directory?
+        File.directory?(File.join(directory, 'app'))
+      end
+
       def has_lib_directory?
         File.directory?(lib_path)
       end
@@ -94,6 +132,7 @@ module Rails
         File.file?(init_path)
       end
 
+
       def evaluate_init_rb(initializer)
         if has_init_file?
           silence_warnings do