expand doesn't work with mock.patch.multiple

[ArthurGW]

When using mock.patch.multiple as a decorator (class or test method), the mocks it creates are passed in as keyword arguments to the test function.

Unfortunately, this is not compatible with expand, as the standalone functions that it generates (parameterized.parameterized.param_as_standalone_func.standalone_func) only take unnamed positional arguments.

The simplest fix seems to be to just add unnamed keyword arguments as well:

@wraps(func)
def standalone_func(*a, **k):
    return func(*(a + p.args), **p.kwargs, **k)

[wolever]

Hey! I'm not able to reproduce this issue; tests with @mock.patch.expand seem to work: https://github.com/wolever/parameterized/pull/156

But please feel free to re-open this issue or create a PR if there's something I've missed!

[ArthurGW]

Hey, @wolever thanks for looking into it!

There's a couple of ways this can still break actually:

• as expected, if you place expand below mock.patch.multiple in the decorator stack (I think this one can be ignored)
• more relevantly, if you use mock.patch.multiple as a class decorator, which shows the same behaviour but I think is supposed to be supported?

For example, if I tweak the test class as below, then I get the error: TypeError: TestParameterizedExpandWithMockPatchMultiple.test_mock_patch_multiple_expand() got an unexpected keyword argument 'umask'.

@mock.patch.multiple("os", umask=mock.DEFAULT, getpid=mock.DEFAULT)
class TestParameterizedExpandWithMockPatchMultiple(TestCase):
    expect([
        "test_mock_patch_multiple_expand(42, 'umask', 'getpid')",
    ])

    @parameterized.expand([(42, )])
    def test_mock_patch_multiple_expand(self, umask, getpid, param):
        missing_tests.remove(
            "test_mock_patch_multiple_expand(%r, %r, %r)" %(
                param, umask._mock_name, getpid._mock_name
            )
        )

Whereas the equivalent non-multiple patches as below work correctly.

@mock.patch("os.getpid")
@mock.patch("os.umask")
class TestParameterizedExpandWithMockPatchMultiple(TestCase):
    expect([
        "test_mock_patch_multiple_expand(42, 'umask', 'getpid')",
    ])

    @parameterized.expand([(42, )])
    def test_mock_patch_multiple_expand(self, umask, getpid, param):
        missing_tests.remove(
            "test_mock_patch_multiple_expand(%r, %r, %r)" %(
                param, umask._mock_name, getpid._mock_name
            )
        )

[wolever]

Ah thank you! I'll drop in a fix this weekend, or feel free to open a PR with test!

[ArthurGW]

No worries!

I could probably drop a PR this weekend if you want. Sadly unable to do it during work time

[wolever]

Wow, that's a weird one! It seems like the class-level @mock.patch.multiple works if the method also has a @mock.patch.multiple applied! But as of https://github.com/wolever/parameterized/pull/161 both should work now.

This fix will be part of the 0.9 release, which should be out by the time you read this.

Thanks for taking the time to submit a report!

[ArthurGW]

Hah! Thanks for the fix :)