1 files changed, 7 insertions, 0 deletions
diff --git a/actionpack/test/controller/polymorphic_routes_test.rb b/actionpack/test/controller/polymorphic_routes_test.rb
index 90c149a830..0d349a360c 100644
--- a/actionpack/test/controller/polymorphic_routes_test.rb
+++ b/actionpack/test/controller/polymorphic_routes_test.rb
@@ -125,5 +125,12 @@ uses_mocha 'polymorphic URL helpers' do
       polymorphic_path(@article, :action => :new)
     end
 
+    def test_polymorphic_path_does_not_modify_arguments
+      expects(:admin_article_responses_url).with(@article)
+      path = [:admin, @article, @response]
+      assert_no_difference 'path.size' do
+        polymorphic_url(path)
+      end
+    end
   end
 end