Merge branch 'master' into nested_has_many_through

Conflicts:
	activerecord/CHANGELOG
	activerecord/lib/active_record/association_preload.rb
	activerecord/lib/active_record/associations.rb
	activerecord/lib/active_record/associations/class_methods/join_dependency.rb
	activerecord/lib/active_record/associations/class_methods/join_dependency/join_association.rb
	activerecord/lib/active_record/associations/has_many_association.rb
	activerecord/lib/active_record/associations/has_many_through_association.rb
	activerecord/lib/active_record/associations/has_one_association.rb
	activerecord/lib/active_record/associations/has_one_through_association.rb
	activerecord/lib/active_record/associations/through_association_scope.rb
	activerecord/lib/active_record/reflection.rb
	activerecord/test/cases/associations/has_many_through_associations_test.rb
	activerecord/test/cases/associations/has_one_through_associations_test.rb
	activerecord/test/cases/reflection_test.rb
	activerecord/test/cases/relations_test.rb
	activerecord/test/fixtures/memberships.yml
	activerecord/test/models/categorization.rb
	activerecord/test/models/category.rb
	activerecord/test/models/member.rb
	activerecord/test/models/reference.rb
	activerecord/test/models/tagging.rb

3 files changed, 30 insertions, 12 deletions

diff --git a/actionpack/lib/abstract_controller/callbacks.rb b/actionpack/lib/abstract_controller/callbacks.rb
index f169ab7c3a..95992c2698 100644
--- a/actionpack/lib/abstract_controller/callbacks.rb
+++ b/actionpack/lib/abstract_controller/callbacks.rb
@@ -13,7 +13,7 @@ module AbstractController
 
     # Override AbstractController::Base's process_action to run the
     # process_action callbacks around the normal behavior.
-    def process_action(method_name)
+    def process_action(method_name, *args)
       run_callbacks(:process_action, method_name) do
         super
       end
diff --git a/actionpack/lib/abstract_controller/layouts.rb b/actionpack/lib/abstract_controller/layouts.rb
index 606f7eedec..4ee54474cc 100644
--- a/actionpack/lib/abstract_controller/layouts.rb
+++ b/actionpack/lib/abstract_controller/layouts.rb
@@ -265,11 +265,11 @@ module AbstractController
           raise ArgumentError, "Layouts must be specified as a String, Symbol, false, or nil"
         when nil
           if name
-            _prefix = "layouts" unless _implied_layout_name =~ /\blayouts/
+            _prefixes = _implied_layout_name =~ /\blayouts/ ? [] : ["layouts"]
 
             self.class_eval <<-RUBY, __FILE__, __LINE__ + 1
               def _layout
-                if template_exists?("#{_implied_layout_name}", #{_prefix.inspect})
+                if template_exists?("#{_implied_layout_name}", #{_prefixes.inspect})
                   "#{_implied_layout_name}"
                 else
                   super
diff --git a/actionpack/lib/abstract_controller/rendering.rb b/actionpack/lib/abstract_controller/rendering.rb
index 91b75273fa..691310d5d2 100644
--- a/actionpack/lib/abstract_controller/rendering.rb
+++ b/actionpack/lib/abstract_controller/rendering.rb
@@ -13,14 +13,15 @@ module AbstractController
   # This is a class to fix I18n global state. Whenever you provide I18n.locale during a request,
   # it will trigger the lookup_context and consequently expire the cache.
   class I18nProxy < ::I18n::Config #:nodoc:
-    attr_reader :i18n_config, :lookup_context
+    attr_reader :original_config, :lookup_context
 
-    def initialize(i18n_config, lookup_context)
-      @i18n_config, @lookup_context = i18n_config, lookup_context
+    def initialize(original_config, lookup_context)
+      original_config = original_config.original_config if original_config.respond_to?(:original_config)
+      @original_config, @lookup_context = original_config, lookup_context
     end
 
     def locale
-      @i18n_config.locale
+      @original_config.locale
     end
 
     def locale=(value)
@@ -60,6 +61,20 @@ module AbstractController
           end
         end
       end
+
+      def parent_prefixes
+        @parent_prefixes ||= begin
+          parent_controller = superclass
+          prefixes = []
+
+          until parent_controller.abstract?
+            prefixes << parent_controller.controller_path
+            parent_controller = parent_controller.superclass
+          end
+
+          prefixes
+        end
+      end
     end
 
     attr_writer :view_context_class
@@ -98,7 +113,7 @@ module AbstractController
     def render_to_string(*args, &block)
       options = _normalize_args(*args, &block)
       _normalize_options(options)
-      render_to_body(options)
+      render_to_body(options).tap { self.response_body = nil }
     end
 
     # Raw rendering of a template to a Rack-compatible body.
@@ -114,9 +129,12 @@ module AbstractController
       view_context.render(options)
     end
 
-    # The prefix used in render "foo" shortcuts.
-    def _prefix
-      controller_path
+    # The prefixes used in render "foo" shortcuts.
+    def _prefixes
+      @_prefixes ||= begin
+        parent_prefixes = self.class.parent_prefixes
+        parent_prefixes.dup.unshift(controller_path)
+      end
     end
 
     private
@@ -156,7 +174,7 @@ module AbstractController
       end
 
       if (options.keys & [:partial, :file, :template, :once]).empty?
-        options[:prefix] ||= _prefix
+        options[:prefixes] ||= _prefixes
       end
 
       options[:template] ||= (options[:action] || action_name).to_s