https://github.com/python/cpython/commit/43f71b0005bc50d929b3a210f3ce5aeea11f904f commit: 43f71b0005bc50d929b3a210f3ce5aeea11f904f branch: 3.13 author: Miss Islington (bot) <[email protected]> committer: gpshead <[email protected]> date: 2026-05-26T12:47:20-07:00 summary:
[3.13] gh-150175: Fix ThreadingMock call_count race condition (GH-150176) (#150180) gh-150175: Fix ThreadingMock call_count race condition (GH-150176) ThreadingMock._increment_mock_call() was not thread-safe. Multiple threads calling the mock simultaneously could lose increments due to race conditions on call_count and other attributes. Fix by overriding _increment_mock_call in ThreadingMixin and wrapping it with the existing _mock_calls_events_lock. (cherry picked from commit 388e023fe1197c1ffed374520ed45df4ac72b8f5) Co-authored-by: saisneha196 <[email protected]> files: A Misc/NEWS.d/next/Library/2026-05-21-11-25-58.gh-issue-150175.8H4Caz.rst M Lib/unittest/mock.py diff --git a/Lib/unittest/mock.py b/Lib/unittest/mock.py index b6dd1c27fee169f..bf32ff6dd3cd9c2 100644 --- a/Lib/unittest/mock.py +++ b/Lib/unittest/mock.py @@ -3102,6 +3102,10 @@ def _mock_call(self, *args, **kwargs): return ret_value + def _increment_mock_call(self, /, *args, **kwargs): + with self._mock_calls_events_lock: + super()._increment_mock_call(*args, **kwargs) + def wait_until_called(self, *, timeout=_timeout_unset): """Wait until the mock object is called. diff --git a/Misc/NEWS.d/next/Library/2026-05-21-11-25-58.gh-issue-150175.8H4Caz.rst b/Misc/NEWS.d/next/Library/2026-05-21-11-25-58.gh-issue-150175.8H4Caz.rst new file mode 100644 index 000000000000000..80fc80d4d50a636 --- /dev/null +++ b/Misc/NEWS.d/next/Library/2026-05-21-11-25-58.gh-issue-150175.8H4Caz.rst @@ -0,0 +1,3 @@ +Fix race condition in :class:`unittest.mock.ThreadingMock` where +concurrent calls could lose increments to ``call_count`` and other +attributes due to a missing lock in ``_increment_mock_call``. _______________________________________________ Python-checkins mailing list -- [email protected] To unsubscribe send an email to [email protected] https://mail.python.org/mailman3//lists/python-checkins.python.org Member address: [email protected]
