Include application's helpers and router helpers by default, but include engine's ones for controllers inside isolated namespace

4 files changed, 30 insertions, 4 deletions

diff --git a/actionpack/lib/action_controller/base.rb b/actionpack/lib/action_controller/base.rb
index 7a1464c2aa..3560ac5b8c 100644
--- a/actionpack/lib/action_controller/base.rb
+++ b/actionpack/lib/action_controller/base.rb
@@ -223,9 +223,13 @@ module ActionController
 
     def self.inherited(klass)
       super
-      klass.helper :all if klass.superclass == ActionController::Base
+      if namespace = klass.parents.detect {|m| m.respond_to?(:_railtie) }
+        klass.helper(all_helpers_from_path(namespace._railtie.config.paths.app.helpers.to_a))
+      else
+        klass.helper :all if klass.superclass == ActionController::Base
+      end
     end
 
     ActiveSupport.run_load_hooks(:action_controller, self)
   end
-end
\ No newline at end of file
+end
diff --git a/actionpack/lib/action_controller/metal/helpers.rb b/actionpack/lib/action_controller/metal/helpers.rb
index 4b6897c5dd..c5d7842db3 100644
--- a/actionpack/lib/action_controller/metal/helpers.rb
+++ b/actionpack/lib/action_controller/metal/helpers.rb
@@ -101,8 +101,12 @@ module ActionController
 
         # Extract helper names from files in <tt>app/helpers/**/*_helper.rb</tt>
         def all_application_helpers
+          all_helpers_from_path(helpers_path)
+        end
+
+        def all_helpers_from_path(path)
           helpers = []
-          Array.wrap(helpers_path).each do |path|
+          Array.wrap(path).each do |path|
             extract  = /^#{Regexp.quote(path.to_s)}\/?(.*)_helper.rb$/
             helpers += Dir["#{path}/**/*_helper.rb"].map { |file| file.sub(extract, '\1') }
           end
diff --git a/actionpack/lib/action_controller/railtie.rb b/actionpack/lib/action_controller/railtie.rb
index 7496dd57b2..23622b19e8 100644
--- a/actionpack/lib/action_controller/railtie.rb
+++ b/actionpack/lib/action_controller/railtie.rb
@@ -4,6 +4,7 @@ require "action_dispatch/railtie"
 require "action_view/railtie"
 require "active_support/deprecation/proxy_wrappers"
 require "active_support/deprecation"
+require "action_controller/railties/routes_helpers"
 
 module ActionController
   class Railtie < Rails::Railtie
@@ -50,7 +51,7 @@ module ActionController
       options.helpers_path         ||= paths.app.helpers.to_a
 
       ActiveSupport.on_load(:action_controller) do
-        include app.routes.url_helpers
+        extend ::ActionController::Railties::RoutesHelpers.with(app.routes)
         include app.routes.mounted_helpers(:app)
         options.each { |k,v| send("#{k}=", v) }
       end
diff --git a/actionpack/lib/action_controller/railties/routes_helpers.rb b/actionpack/lib/action_controller/railties/routes_helpers.rb
new file mode 100644
index 0000000000..a23f703f0b
--- /dev/null
+++ b/actionpack/lib/action_controller/railties/routes_helpers.rb
@@ -0,0 +1,17 @@
+module ActionController
+  module Railties
+    module RoutesHelpers
+      def self.with(routes)
+        Module.new do
+          define_method(:inherited) do |klass|
+            super(klass)
+            if namespace = klass.parents.detect {|m| m.respond_to?(:_railtie) }
+              routes = namespace._railtie.routes
+            end
+            klass.send(:include, routes.url_helpers)
+          end
+        end
+      end
+    end
+  end
+end