https://github.com/python/cpython/commit/f75028f7ceebee4cbeb46bf040834e2005d57436 commit: f75028f7ceebee4cbeb46bf040834e2005d57436 branch: main author: Ivy Xu <[email protected]> committer: JelleZijlstra <[email protected]> date: 2026-07-03T10:42:06+02:00 summary:
gh-150641: Fix evaluating forward references in STRING format can 'leak' internal names in `typing` (#150648) Co-authored-by: Jelle Zijlstra <[email protected]> files: A Misc/NEWS.d/next/Library/2026-05-31-14-39-25.gh-issue-150641.LLIhd1.rst M Lib/test/test_typing.py M Lib/typing.py diff --git a/Lib/test/test_typing.py b/Lib/test/test_typing.py index ed07503cd63f12..17574c7f03d8e1 100644 --- a/Lib/test/test_typing.py +++ b/Lib/test/test_typing.py @@ -7587,6 +7587,18 @@ def test_with_module(self): typing.evaluate_forward_ref( fwdref_module.fw,) + def test_evaluate_forward_ref_string_format(self): + # Test evaluating forward references in STRING format + # does not 'leak' internal names + # See https://github.com/python/cpython/issues/150641 + + def f(arg: unknown | str | int | list[str] | tuple[int, ...]): ... + + ref = annotationlib.get_annotations(f, format=annotationlib.Format.FORWARDREF)['arg'] + self.assertEqual( + typing.evaluate_forward_ref(ref, format=annotationlib.Format.STRING), + "unknown | str | int | list[str] | tuple[int, ...]", + ) class CollectionsAbcTests(BaseTestCase): diff --git a/Lib/typing.py b/Lib/typing.py index 1579f492003f74..933336ff4cf37e 100644 --- a/Lib/typing.py +++ b/Lib/typing.py @@ -1019,7 +1019,7 @@ def evaluate_forward_ref( """ if format == annotationlib.Format.STRING: - return forward_ref.__forward_arg__ + return forward_ref.__resolved_str__ if forward_ref.__forward_arg__ in _recursive_guard: return forward_ref diff --git a/Misc/NEWS.d/next/Library/2026-05-31-14-39-25.gh-issue-150641.LLIhd1.rst b/Misc/NEWS.d/next/Library/2026-05-31-14-39-25.gh-issue-150641.LLIhd1.rst new file mode 100644 index 00000000000000..eba899c96fcd26 --- /dev/null +++ b/Misc/NEWS.d/next/Library/2026-05-31-14-39-25.gh-issue-150641.LLIhd1.rst @@ -0,0 +1,2 @@ +Fix bug where :func:`typing.evaluate_forward_ref` with the ``STRING`` format +could leak internal names used by the annotation machinery. _______________________________________________ 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]
