From c5d0eb473a9a1dc486dd2dd60603463435e49da4 Mon Sep 17 00:00:00 2001 From: Sebastiaan Zeeff <33516116+SebastiaanZ@users.noreply.github.com> Date: Mon, 28 Oct 2019 15:56:34 +0100 Subject: Change generation of child mocks - https://docs.python.org/3/library/unittest.mock.html We previously used an override of the `__new__` method to prevent our custom mock types from instantiating their children with their own type instead of a general mock type like `MagicMock` or `Mock`. As it turns out, the Python documentation suggests another method of doing this that does not involve overriding `__new__`. This commit implements this new method to make sure we're using the idiomatic way of handling this. The suggested method is overriding the `_get_child_mock` method in the subclass. To make our code DRY, I've created a mixin that should come BEFORE the mock type we're subclassing in the MRO. --- In addition, I have also added this new mixin to our `AsyncMock` class to make sure that its `__call__` method returns a proper mock object after it has been awaited. This makes sure that subsequent attribute access on the returned object is mocked as expected. --- tests/test_helpers.py | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) (limited to 'tests/test_helpers.py') diff --git a/tests/test_helpers.py b/tests/test_helpers.py index f08239981..62007ff4e 100644 --- a/tests/test_helpers.py +++ b/tests/test_helpers.py @@ -221,10 +221,10 @@ class DiscordMocksTests(unittest.TestCase): @unittest.mock.patch(f'{__name__}.DiscordMocksTests.subTest') def test_the_custom_mock_methods_test(self, subtest_mock): """The custom method test should raise AssertionError for invalid methods.""" - class FakeMockBot(helpers.AttributeMock, unittest.mock.MagicMock): + class FakeMockBot(helpers.GetChildMockMixin, unittest.mock.MagicMock): """Fake MockBot class with invalid attribute/method `release_the_walrus`.""" - attribute_mocktype = unittest.mock.MagicMock + child_mock_type = unittest.mock.MagicMock def __init__(self, **kwargs): super().__init__(spec=helpers.bot_instance, **kwargs) @@ -331,6 +331,18 @@ class MockObjectTests(unittest.TestCase): self.assertFalse(instance_one != instance_two) self.assertTrue(instance_one != instance_three) + def test_get_child_mock_mixin_accepts_mock_seal(self): + """The `GetChildMockMixin` should support `unittest.mock.seal`.""" + class MyMock(helpers.GetChildMockMixin, unittest.mock.MagicMock): + + child_mock_type = unittest.mock.MagicMock + pass + + mock = MyMock() + unittest.mock.seal(mock) + with self.assertRaises(AttributeError, msg="MyMock.shirayuki"): + mock.shirayuki = "hello!" + def test_spec_propagation_of_mock_subclasses(self): """Test if the `spec` does not propagate to attributes of the mock object.""" test_values = ( @@ -346,7 +358,7 @@ class MockObjectTests(unittest.TestCase): mock = mock_type() self.assertTrue(isinstance(mock, mock_type)) attribute = getattr(mock, valid_attribute) - self.assertTrue(isinstance(attribute, mock_type.attribute_mocktype)) + self.assertTrue(isinstance(attribute, mock_type.child_mock_type)) def test_async_mock_provides_coroutine_for_dunder_call(self): """Test if AsyncMock objects have a coroutine for their __call__ method.""" -- cgit v1.2.3