1 files changed, 48 insertions, 19 deletions

diff --git a/railties/lib/rails/engine.rb b/railties/lib/rails/engine.rb
index d652c6b7fe..5c1af99fe2 100644
--- a/railties/lib/rails/engine.rb
+++ b/railties/lib/rails/engine.rb
@@ -330,6 +330,17 @@ module Rails
   #
   #   MyEngine::Engine.load_seed
   #
+  # == Loading priority
+  #
+  # In order to change engine's priority you can use config.railties_order in main application.
+  # It will affect the priority of loading views, helpers, assets and all the other files
+  # related to engine or application.
+  #
+  # Example:
+  #
+  #   # load Blog::Engine with highest priority, followed by application and other railties
+  #   config.railties_order = [Blog::Engine, :main_app, :all]
+  #
   class Engine < Railtie
     autoload :Configuration, "rails/engine/configuration"
     autoload :Railties,      "rails/engine/railties"
@@ -371,20 +382,28 @@ module Rails
         self.routes.default_scope = { :module => ActiveSupport::Inflector.underscore(mod.name) }
         self.isolated = true
 
-        unless mod.respond_to?(:_railtie)
-          name = engine_name
-          _railtie = self
+        unless mod.respond_to?(:railtie_namespace)
+          name, railtie = engine_name, self
+
           mod.singleton_class.instance_eval do
-            define_method(:_railtie) do
-              _railtie
-            end
+            define_method(:railtie_namespace) { railtie }
 
             unless mod.respond_to?(:table_name_prefix)
-              define_method(:table_name_prefix) do
-                "#{name}_"
-              end
+              define_method(:table_name_prefix) { "#{name}_" }
             end
-         end
+
+            unless mod.respond_to?(:use_relative_model_naming?)
+              class_eval "def use_relative_model_naming?; true; end", __FILE__, __LINE__
+            end
+
+            unless mod.respond_to?(:railtie_helpers_paths)
+              define_method(:railtie_helpers_paths) { railtie.helpers_paths }
+            end
+
+            unless mod.respond_to?(:railtie_routes_url_helpers)
+              define_method(:railtie_routes_url_helpers) { railtie.routes_url_helpers }
+            end
+          end
         end
       end
 
@@ -429,13 +448,6 @@ module Rails
     def helpers
       @helpers ||= begin
         helpers = Module.new
-
-        helpers_paths = if config.respond_to?(:helpers_paths)
-          config.helpers_paths
-        else
-          paths["app/helpers"].existent
-        end
-
         all = ActionController::Base.all_helpers_from_path(helpers_paths)
         ActionController::Base.modules_for_helpers(all).each do |mod|
           helpers.send(:include, mod)
@@ -444,6 +456,14 @@ module Rails
       end
     end
 
+    def helpers_paths
+      paths["app/helpers"].existent
+    end
+
+    def routes_url_helpers
+      routes.url_helpers
+    end
+
     def app
       @app ||= begin
         config.middleware = config.middleware.merge_into(default_middleware_stack)
@@ -471,10 +491,19 @@ module Rails
       @routes
     end
 
+    def ordered_railties
+      railties.all + [self]
+    end
+
     def initializers
       initializers = []
-      railties.all { |r| initializers += r.initializers }
-      initializers += super
+      ordered_railties.each do |r|
+        if r == self
+          initializers += super
+        else
+          initializers += r.initializers
+        end
+      end
       initializers
     end