from mock import MagicMock class SomeModel(object): foo = "f**" bar = "b**" m = MagicMock(spec=SomeModel)
Here we create a mock object which mimics the interface of
as we would expect, returning mock values for things we access.
>>> m.foo <MagicMock name='mock.foo' id='4506756880'> >>> m.bar <MagicMock name='mock.bar' id='4506754192'>
Let’s see what happens if we call something else:
>>> m.baz Traceback (most recent call last): File "<stdin>", line 1, in <module> File ".../env/lib/python2.7/site-packages/mock.py", line 658, in __getattr__ raise AttributeError("Mock object has no attribute %r" % name) AttributeError: Mock object has no attribute 'baz'
It will fail loudly while a mock object without a spec would have returned a mock value as it did in the previous example.
But the magic doesn’t end there. You can still set additional attributes/methods “by hand” and have them not fail even if they aren’t part of the original spec.
>>> m.baz = "bazzzzz" >>> m.baz 'bazzzzz'
Learning new things makes me happy. 😀