2 files changed, 4 insertions, 1 deletions
diff --git a/actionview/lib/action_view/helpers/controller_helper.rb b/actionview/lib/action_view/helpers/controller_helper.rb
index 74ef25f7c1..3569fba8c6 100644
--- a/actionview/lib/action_view/helpers/controller_helper.rb
+++ b/actionview/lib/action_view/helpers/controller_helper.rb
@@ -14,6 +14,7 @@ module ActionView
         if @_controller = controller
           @_request = controller.request if controller.respond_to?(:request)
           @_config  = controller.config.inheritable_copy if controller.respond_to?(:config)
+          @_default_form_builder = controller.default_form_builder if controller.respond_to?(:default_form_builder)
         end
       end
 
diff --git a/actionview/lib/action_view/helpers/form_helper.rb b/actionview/lib/action_view/helpers/form_helper.rb
index ece117b547..7fdeca5ea8 100644
--- a/actionview/lib/action_view/helpers/form_helper.rb
+++ b/actionview/lib/action_view/helpers/form_helper.rb
@@ -114,6 +114,8 @@ module ActionView
       include ModelNaming
       include RecordIdentifier
 
+      attr_internal :default_form_builder
+
       # Creates a form that allows the user to create or update the attributes
       # of a specific model object.
       #
@@ -1233,7 +1235,7 @@ module ActionView
         end
 
         def default_form_builder_class
-          builder = ActionView::Base.default_form_builder
+          builder = default_form_builder || ActionView::Base.default_form_builder
           builder.respond_to?(:constantize) ? builder.constantize : builder
         end
     end