如何验证python中没有调用的mock方法?

时间:2014-05-25 12:58:10

标签: python mocking

在我的代码中,我使用assert_any_call()来验证django模型过滤器发生的一系列调用,现在我需要验证它的反向情况,如assert_not_called(args)。

在python中是否有任何断言声明来实现这一点?

1 个答案:

答案 0 :(得分:2)

最简单的方法是使用Mock.call_args_list

assert call(None, a=1, b="") not in mocked_func.call_args_list, "Called with invalid args."

如果您需要方法,请使用:

class NotCalledMagicMock(unittest.mock.MagicMock):
    def assert_not_called(_mock_self, *args, **kwargs):
        self = _mock_self
        if self.call_args is None:
            return

        expected = self._call_matcher((args, kwargs))
        if any(self._call_matcher(ca) == expected for ca in self.call_args_list):
            cause = expected if isinstance(expected, Exception) else None
            raise AssertionError(
                '%r found in call list' % (self._format_mock_call_signature(args, kwargs),)
            ) from cause

要使用此类,请将此装饰器放在测试函数之前:

@unittest.mock.patch("unittest.mock.MagicMock", NotCalledMagicMock)

或者使用以下方式制作你的模仿:

func_b_mock = NotCalledMagicMock()

使用该方法(其中func_b_mock是由patch生成的模拟):

func_b_mock.assert_not_called([12], a=4)

当它失败时,会引发AssertionError之类的:

Traceback (most recent call last):
  File "your_test.py", line 34, in <module>
    test_a()
  File "/usr/lib/python3.4/unittest/mock.py", line 1136, in patched
    return func(*args, **keywargs)
  File "your_test.py", line 33, in test_a
    func_b_mock.assert_not_called([1])
  File "your_test.py", line 20, in assert_not_called
    ) from cause
AssertionError: 'func_b([1])' found in call list