I tried to use unittest2's defaultTestLoader.loadTestsFromNames() to load a specific test from a test case derived from the standard Python 2.6 unittest.TestCase. It would not be recongized.

The attached patch fixes the problem.

sigh I think you're correct. Thanks for the report and the fix.

We're hitting this problem in Django as well, FWIW; we've applied this patch to our bundled unittest2, but it still breaks if the user has installed unittest2 from PyPI (as we privilege the version from PyPI over our bundled version).

The Django ticket tracking this is https://code.djangoproject.com/ticket/20437

I'm planning a new release with a couple of bugfixes including this one.

So, need to fix this upstream ideally to make backports easier.

I think this is a unittest2 specific issue. unittest2 needs to check for subclasses of unittest.TestCase, not just TestCase (which will mean unittest2.TestCase).