How to fix: Drupal Simpletests do not show up in tests list?

Your Simpletest test files do not show up in the lists of available tests on "admin/config/development/testing"?

Then you may have missed one of the following line in your modules ".info" - File:

files[] = my_module.test
testing_api = 2.x

The second line made the tests showing up in my case. Did you encounter the same problem?