diff --git a/railties/helpers/test_helper.rb b/railties/helpers/test_helper.rb
index 9f1926950f..b9fe2517c8 100644
--- a/railties/helpers/test_helper.rb
+++ b/railties/helpers/test_helper.rb
@@ -2,7 +2,7 @@ ENV["RAILS_ENV"] = "test"
 require File.expand_path(File.dirname(__FILE__) + "/../config/environment")
 require 'test_help'
 
-class Test::Unit::TestCase
+class ActiveSupport::TestCase
   # Transactional fixtures accelerate your tests by wrapping each test method
   # in a transaction that's rolled back on completion.  This ensures that the
   # test database remains unchanged so your fixtures don't have to be reloaded