How to extend a test class of dependent module I am creating a module with dependency on another contrib module. When I am trying to extend the test class in dependent module, it works fine locally(using test UI). However when I try to test my new module in qa.drupal.org it throws error saying that the  'Class not found' as the dependency module is not enabled.
You can use function module_load_include to include file in your module. Class not found because main class not include in your case.