def test_runUntilFailure(self):
        """
        Test that the runUntilFailure method of the runner actually fail after
        a few runs.
        """
        result = self.runner.runUntilFailure(self.test)
        self.assertEqual(result.testsRun, 1)
        self.assertFalse(result.wasSuccessful())
        self.assertEqual(self._getFailures(result), 1)

        Test that the runUntilFailure method of the runner actually fail after
        a few runs.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/trial/test/test_runner.py