diff --git a/actionpack/lib/action_controller/test_case.rb b/actionpack/lib/action_controller/test_case.rb
index 94f18cefc3..e012fa617e 100644
--- a/actionpack/lib/action_controller/test_case.rb
+++ b/actionpack/lib/action_controller/test_case.rb
@@ -1,4 +1,5 @@
 require 'rack/session/abstract/id'
+require 'active_support/core_ext/hash/conversions'
 require 'active_support/core_ext/object/to_query'
 require 'active_support/core_ext/module/anonymous'
 require 'active_support/core_ext/hash/keys'