How do you mock patch a python class and get a new Mock object for each instantiation?
Here's a quick'n'dirty example to get you going:
import mock
import unittest
class ClassToPatch():
def __init__(self, *args):
pass
def some_func(self):
return id(self)
class UUT():
def __init__(self, *args):
resource_1 = ClassToPatch()
resource_2 = ClassToPatch()
self.test_property = (resource_1.some_func(), resource_2.some_func())
class TestCase1(unittest.TestCase):
@mock.patch('__main__.ClassToPatch', autospec = True)
def test_1(self, mock1):
ctpMocks = [mock.Mock(), mock.Mock()]
ctpMocks[0].some_func.return_value = "funky"
ctpMocks[1].some_func.return_value = "monkey"
mock1.side_effect = ctpMocks
u = UUT()
self.assertEqual(u.test_property, ("funky", "monkey"))
if __name__ == '__main__':
unittest.main()
I've added test_property
to UUT so that the unit test does something useful. Now, without the mock test_property
should be a tuple containing the ids of the two ClassToPatch
instances. But with the mock it should be the tuple: ("funky", "monkey")
.
I've used the side_effect
property of the mock object so that a different instance of ClassToPatch
is returned on each call in the UUT
initialiser.
Hope this helps.
Edit: Oh, by the way, when I run the unit test I get:
.
----------------------------------------------------------------------
Ran 1 test in 0.004s
OK