Python-如何断言没有使用特定参数调用模拟对象？

Question

我意识到 unittest.mock 对象现在有一个可用的assert_not_called方法，但我正在寻找的是一个assert_not_called_with。有这样的事情吗？我查看了Google，没有看到任何东西，当我尝试仅使用mock_function.assert_not_called_with（...）时，它引发了一个AttributeError，这意味着该函数不存在该名称。

with self.assertRaises(AssertionError):
    mock_function.assert_called_with(arguments_I_want_to_test)

这有效，但如果我想进行几次这样的调用，则会使代码混乱。

断言没有使用Mock调用函数/方法

Answer 1

使用Pytest，我断言“AssertionError”被调用:

import pytest
from unittest.mock import Mock


def test_something():
    something.foo = Mock()
    
    # Test that something.foo(bar) is not called.
    with pytest.raises(AssertionError):
        something.foo.assert_called_with(bar)

Answer 2

另一个使用模拟通话历史记录的解决方案：

from unittest.mock import call

assert call(arguments_I_want_to_test) not in mock_function.mock_calls

Answer 3

您可以自行将assert_not_called_with方法添加到 unittest.mock.Mock 中：

from unittest.mock import Mock

def assert_not_called_with(self, *args, **kwargs):
    try:
        self.assert_called_with(*args, **kwargs)
    except AssertionError:
        return
    raise AssertionError('Expected %s to not have been called.' % self._format_mock_call_signature(args, kwargs))

Mock.assert_not_called_with = assert_not_called_with

因此：

m = Mock()
m.assert_not_called_with(1, 2, a=3)
m(3, 4, b=5)
m.assert_not_called_with(3, 4, b=5)

输出：

AssertionError: Expected mock(3, 4, b=5) to not have been called.