3 files changed, 13 insertions, 5 deletions
diff --git a/actionpack/lib/abstract_controller/rendering.rb b/actionpack/lib/abstract_controller/rendering.rb
index 575b9807d0..242c44a6eb 100644
--- a/actionpack/lib/abstract_controller/rendering.rb
+++ b/actionpack/lib/abstract_controller/rendering.rb
@@ -32,6 +32,8 @@ module AbstractController
     def render(*args, &block)
       options = _normalize_render(*args, &block)
       self.response_body = render_to_body(options)
+      _process_format(rendered_format)
+      self.response_body
     end
 
     # Raw rendering of a template to a string.
@@ -98,6 +100,11 @@ module AbstractController
       options
     end
 
+    # Process the rendered format.
+    # :api: private
+    def _process_format(format)
+    end
+
     # Normalize args and options.
     # :api: private
     def _normalize_render(*args, &block)
diff --git a/actionpack/lib/action_controller/metal/mime_responds.rb b/actionpack/lib/action_controller/metal/mime_responds.rb
index 834d44f045..66dabd821f 100644
--- a/actionpack/lib/action_controller/metal/mime_responds.rb
+++ b/actionpack/lib/action_controller/metal/mime_responds.rb
@@ -364,9 +364,7 @@ module ActionController #:nodoc:
       format = collector.negotiate_format(request)
 
       if format
-        self.content_type ||= format.to_s
-        lookup_context.formats = [format.to_sym]
-        lookup_context.rendered_format = lookup_context.formats.first
+        _process_format(format)
         collector
       else
         raise ActionController::UnknownFormat
diff --git a/actionpack/lib/action_controller/metal/rendering.rb b/actionpack/lib/action_controller/metal/rendering.rb
index 37dee1738f..90f0ef0b1c 100644
--- a/actionpack/lib/action_controller/metal/rendering.rb
+++ b/actionpack/lib/action_controller/metal/rendering.rb
@@ -12,8 +12,6 @@ module ActionController
     def render(*args) #:nodoc:
       raise ::AbstractController::DoubleRenderError if self.response_body
       super
-      self.content_type ||= rendered_format.to_s
-      self.response_body
     end
 
     # Overwrite render_to_string because body can now be set to a rack body.
@@ -38,6 +36,11 @@ module ActionController
 
     private
 
+    def _process_format(format)
+      super
+      self.content_type ||= format.to_s
+    end
+
     # Normalize arguments by catching blocks and setting them on :update.
     def _normalize_args(action=nil, options={}, &blk) #:nodoc:
       options = super