Fix rendering of layouts.

actionpack/lib/abstract_controller/rendering.rb

@@ -157,7 +157,8 @@ module AbstractController
         options[:_template_name] = options[:file]
       end
 
-      name = (options[:_template_name] || action_name).to_s
+      name = (options[:_template_name] || options[:action] || action_name).to_s
+      options[:_prefix] ||= _prefix if (options.keys & [:partial, :file, :template]).empty?
 
       options[:_template] ||= with_template_cache(name) do
         find_template(name, { :formats => formats }, options)

actionpack/lib/action_controller/metal/rendering.rb

@@ -58,11 +58,6 @@ module ActionController
           options.merge! :partial => action
         end
 
-        if (options.keys & [:partial, :file, :template, :text, :inline]).empty?
-          options[:_template_name] ||= options[:action]
-          options[:_prefix] = _prefix
-        end
-
         if options[:status]
           options[:status] = Rack::Utils.status_code(options[:status])
         end

actionpack/test/abstract/render_test.rb

@@ -11,13 +11,13 @@ module AbstractController
       end
 
       self.view_paths = [ActionView::FixtureResolver.new(
-        "default.erb" => "With Default",
         "template.erb" => "With Template",
+        "renderer/default.erb" => "With Default",
         "renderer/string.erb" => "With String",
         "renderer/symbol.erb" => "With Symbol",
+        "renderer/template_name.erb" => "With Template Name",
         "string/with_path.erb" => "With String With Path",
-        "some/file.erb" => "With File",
-        "template_name.erb" => "With Template Name"
+        "some/file.erb" => "With File"
       )]
 
       def template