'If a warnings filter has been installed which turns warnings into
exceptions, tests which emit those warnings but flush them do not have
an error added to the reporter.'

def test_flushedWarningsConfiguredAsErrors(self):

    class CustomWarning(Warning, ):
        pass
    result = TestResult()
    case = Mask.MockTests('test_flushed')
    case.category = CustomWarning
    originalWarnings = warnings.filters[:]
    try:
        warnings.simplefilter('error')
        case.run(result)
        self.assertEqual(result.errors, [])
    finally:
        warnings.filters[:] = originalWarnings
