Non-test methods in a Python TestCase

I believe that you don't have to do anything. Your helper methods should just not start with test_.

The only methods that unittest will execute [1] are setUp, anything that starts with test, and tearDown [2], in that order. You can make helper methods and call them anything except for those three things, and they will not be executed by unittest.

You can think of setUp as __init__: if you're generating mock objects that are used by multiple tests, create them in setUp.

def setUp(self):
    self.mock_obj = MockObj()

[1]: This is not entirely true, but these are the main 3 groups of methods that you can concentrate on when writing tests.

[2]: For legacy reasons, unittest will execute both test_foo and testFoo, but test_foo is the preferred style these days. setUp and tearDown should appear as such.

The test runner will only directly execute methods beginning with test, so just make sure your helper methods' names don't begin with test.