def test_usage_error_message(self):
        fake_sys_module = FakeSysModule(argv=[])
        script = BuildScript(sys_module=fake_sys_module)

        try:
            script.main(top_level=FLOCKER_PATH)
        except SystemExit:
            pass
        self.assertEqual(
            'Wrong number of arguments.',
            fake_sys_module.stderr.getvalue().splitlines()[-1]
        )
Mock sending a transactional message via sendmail.
dataset/ETHPy150Open ClusterHQ/flocker/admin/test/test_packaging.py/BuildScriptTests.test_usage_error_message--crossover with--dataset/ETHPy150Open Pylons/pyramid_mailer/pyramid_mailer/mailer.py/DummyMailer.send_sendmail