How to call self in a mock method of an object in Python?

mocking, python

Solution

You need `autospec=True`

def mock_save(self):
    assert self.attr == 'dest_val'
with mock.patch.object(Item, "save", autospec=True) as save:
    save.side_effect = mock_save
    func_to_call()

Problem

I try to test some codes which don't return anything but save the result to the DB. By mocking the save method, I wish to check whether things have been processed correctly: ``` def mock_save(self): assert(self.attr, 'dest_val') with mock.patch.object(Item, "save", create=True) as save: save.side_effect = mock_save func_to_call() //in func_to_call, I call item.save() ``` However, it seems that this is not allowed. It says that the number of argument mismatch. If I do def `mock_save()`, it won't work. How can I have a reference to the object which the mock method act upon too? (I saw it in another thread that is applicable to `__init__` method which can be called directly from the class).

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