def _removeTestAtIndex(self, index):
        """Stop holding a reference to the TestCase at index."""
        try:
            test = self._tests[index]
        except TypeError:
            # support for suite implementations that have overriden self._tests
            pass
        else:
            # Some unittest tests add non TestCase/TestSuite objects to
            # the suite.
            if hasattr(test, 'countTestCases'):
                self._removed_tests += test.countTestCases()
            self._tests[index] = None