2 files changed, 4 insertions, 3 deletions
diff --git a/actionview/lib/action_view/rendering.rb b/actionview/lib/action_view/rendering.rb
index e5e2771323..ac861c44d4 100644
--- a/actionview/lib/action_view/rendering.rb
+++ b/actionview/lib/action_view/rendering.rb
@@ -118,7 +118,8 @@ module ActionView
           renderer.render_to_object(context, options)
         end
 
-        @rendered_format = Template::Types[rendered_template.format]
+        rendered_format = rendered_template.format || lookup_context.formats.first
+        @rendered_format = Template::Types[rendered_format]
 
         rendered_template.body
       end
diff --git a/actionview/lib/action_view/template/resolver.rb b/actionview/lib/action_view/template/resolver.rb
index 1c463efbb2..f2b8b1166d 100644
--- a/actionview/lib/action_view/template/resolver.rb
+++ b/actionview/lib/action_view/template/resolver.rb
@@ -294,12 +294,12 @@ module ActionView
           if handler.respond_to?(:default_format) # default_format can return nil
             handler.default_format
           else
-            query_format
+            nil
           end
         end
 
         # Template::Types[format] and handler.default_format can return nil
-        [handler, format || query_format, variant]
+        [handler, format, variant]
       end
   end