New submission from Karthikeyan Singaravelan <tir.kar...@gmail.com>:
The following program causes AttributeError while retrieving the spec signature of a call. It seems that not all mocks specced should have _spec_signature where if autospec is used and the mock is attached with attach_mock then the "mock" attribute has the correct object from which _spec_signature has to be derived. On the attribute being not present we can fallback to the sig being None. This can be workaround by disabling autospec but since this is present in 3.7.5RC1 and 3.8.0RC1 I am tagging it as regression. I am also attaching a patch with script to reproduce this that should pass with the patch. I will try to make a PR tonight. Sorry for the last minute report I just stumbled upon this while debugging https://bugs.python.org/issue21478#msg354489. This change was introduced as part of https://bugs.python.org/issue36871 by me. I am tagging the nosy list from issue for review of the patch. import unittest from unittest.mock import patch, Mock, call, ANY class Foo: def set_foo(self, val): pass class FooTest(unittest.TestCase): @patch(f"{__name__}.Foo.set_foo", autospec=True) def test_autospec_attach_mock_assert(self, mock_set_foo): manager = Mock() manager.attach_mock(mock_set_foo, "set_foo_func") obj = Foo() obj.set_foo(3) manager.assert_has_calls([call.set_foo_func(ANY, 3)]) if __name__ == "__main__": unittest.main() ➜ Python-3.7.5rc1 ./python autospec_regression.py E ====================================================================== ERROR: test_autospec_attach_mock_assert (__main__.FooTest) ---------------------------------------------------------------------- Traceback (most recent call last): File "/home/xtreak/Python-3.7.5rc1/Lib/unittest/mock.py", line 1255, in patched return func(*args, **keywargs) File "autospec_regression.py", line 16, in test_autospec_attach_mock_assert manager.assert_has_calls([call.set_foo_func(ANY, 3)]) File "/home/xtreak/Python-3.7.5rc1/Lib/unittest/mock.py", line 897, in assert_has_calls expected = [self._call_matcher(c) for c in calls] File "/home/xtreak/Python-3.7.5rc1/Lib/unittest/mock.py", line 897, in <listcomp> expected = [self._call_matcher(c) for c in calls] File "/home/xtreak/Python-3.7.5rc1/Lib/unittest/mock.py", line 812, in _call_matcher sig = self._get_call_signature_from_name(_call[0]) File "/home/xtreak/Python-3.7.5rc1/Lib/unittest/mock.py", line 798, in _get_call_signature_from_name sig = child._spec_signature AttributeError: 'function' object has no attribute '_spec_signature' ---------------------------------------------------------------------- Ran 1 test in 0.003s FAILED (errors=1) Patch : ➜ Python-3.7.5rc1 diff -u Lib/unittest/mock.py Lib/unittest/mock_patched.py --- Lib/unittest/mock.py 2019-10-01 22:53:17.000000000 +0530 +++ Lib/unittest/mock_patched.py 2019-10-14 19:18:00.038416294 +0530 @@ -795,7 +795,16 @@ break else: children = child._mock_children - sig = child._spec_signature + # If an autospecced object is attached using attach_mock the + # child would be a function with mock object as attribute from + # which signature has to be derived. If there is no signature + # attribute then fallback to None to ensure old signature is + # not used. + child = _extract_mock(child) + try: + sig = child._spec_signature + except AttributeError: + sig = None return sig ---------- components: Library (Lib) keywords: 3.7regression, 3.8regression messages: 354635 nosy: cjw296, gregory.p.smith, lisroach, lukasz.langa, mariocj89, michael.foord, ned.deily, xtreak priority: normal severity: normal status: open title: AttributeError on asserting autospecced mock object added using attach_mock versions: Python 3.7, Python 3.8, Python 3.9 _______________________________________ Python tracker <rep...@bugs.python.org> <https://bugs.python.org/issue38473> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
