python - Python单元测试类属性

Question

我试图弄清楚是否有办法（单元测试）验证属性和 setter 是否被实际调用来设置 name 属性。

class DummyName:
    def __init__(self):
        self.name = ''

    @property
    def name(self):
        return self.name

    @name.setter
    def name(self, name):
        if not isinstance(name, basestring):
            raise Exception('Name must be a string.')
        self.name = name

试图做这样的事情......

@mock.patch.object(DummyName, 'name', new_callable=PropertyMock)
def testNameProperty(self, mock_name):
    MockName = Mock()
    mock_name.return_value = MockName
    dummyName = DummyName()
    dummyName.name = 'test_name'
    # assert setter is called to set the name
    # assert name is called to get the name
    # assert name is 'test_name'

似乎从未访问过 name() 和 setter。有人有更好的主意吗？谢谢！

Answer 1

通过使用这样的模拟，您已经覆盖了您要测试的代码。模拟用于被测代码外部的调用。

对此代码的适当测试是断言如果您传递的不是字符串，则会引发异常。

def testNameProperty(self):
    dummyName = DummyName()
    with self.assertRaises(Exception):
        dummyName.name = 12345

Answer 2

你的类需要继承自object.

class DummyName(object):
    def __init__(self):
        self._name = ''

    @property
    def name(self):
        return self._name

    @name.setter
    def name(self, name):
        if not isinstance(name, basestring):
            raise Exception('Name must be a string.')
        self._name = name

您还需要name在类内部使用不同的变量，否则您将达到最大递归。