https://github.com/python/cpython/commit/66d06360252cd3dc26edfbe5d30c51aa750... commit: 66d06360252cd3dc26edfbe5d30c51aa7505524a branch: 3.13 author: Miss Islington (bot) <31488909+miss-islington@users.noreply.github.com> committer: kumaraditya303 <kumaraditya@python.org> date: 2025-01-13T13:20:49Z summary: [3.13] gh-128078: Clear exception in `anext` before calling `_PyGen_SetStopIterationValue` (GH-128780) (#128785) gh-128078: Clear exception in `anext` before calling `_PyGen_SetStopIterationValue` (GH-128780) (cherry picked from commit 76ffaef729c91bb79da6df2ade48f3ec51118300) Co-authored-by: Bénédikt Tran <10796600+picnixz@users.noreply.github.com> Co-authored-by: Kumar Aditya <kumaraditya@python.org> files: A Misc/NEWS.d/next/Core_and_Builtins/2025-01-13-12-48-30.gh-issue-128078.qOsl9B.rst M Lib/test/test_asyncgen.py M Objects/genobject.c M Objects/iterobject.c diff --git a/Lib/test/test_asyncgen.py b/Lib/test/test_asyncgen.py index 4f2278bb263681..16164492b25690 100644 --- a/Lib/test/test_asyncgen.py +++ b/Lib/test/test_asyncgen.py @@ -1152,6 +1152,23 @@ async def run(): self.loop.run_until_complete(run()) + def test_async_gen_asyncio_anext_tuple_no_exceptions(self): + # StopAsyncIteration exceptions should be cleared. + # See: https://github.com/python/cpython/issues/128078. + + async def foo(): + if False: + yield (1, 2) + + async def run(): + it = foo().__aiter__() + with self.assertRaises(StopAsyncIteration): + await it.__anext__() + res = await anext(it, ('a', 'b')) + self.assertEqual(res, ('a', 'b')) + + self.loop.run_until_complete(run()) + def test_async_gen_asyncio_anext_stopiteration(self): async def foo(): try: diff --git a/Misc/NEWS.d/next/Core_and_Builtins/2025-01-13-12-48-30.gh-issue-128078.qOsl9B.rst b/Misc/NEWS.d/next/Core_and_Builtins/2025-01-13-12-48-30.gh-issue-128078.qOsl9B.rst new file mode 100644 index 00000000000000..498864a0aa3145 --- /dev/null +++ b/Misc/NEWS.d/next/Core_and_Builtins/2025-01-13-12-48-30.gh-issue-128078.qOsl9B.rst @@ -0,0 +1,2 @@ +Fix a :exc:`SystemError` when using :func:`anext` with a default tuple +value. Patch by Bénédikt Tran. diff --git a/Objects/genobject.c b/Objects/genobject.c index 92cd8c61e7e9ca..524cda1487813c 100644 --- a/Objects/genobject.c +++ b/Objects/genobject.c @@ -604,6 +604,7 @@ gen_iternext(PyGenObject *gen) int _PyGen_SetStopIterationValue(PyObject *value) { + assert(!PyErr_Occurred()); PyObject *e; if (value == NULL || diff --git a/Objects/iterobject.c b/Objects/iterobject.c index 135ced9ea1f268..ebb342ff109222 100644 --- a/Objects/iterobject.c +++ b/Objects/iterobject.c @@ -384,6 +384,7 @@ anextawaitable_iternext(anextawaitableobject *obj) return result; } if (PyErr_ExceptionMatches(PyExc_StopAsyncIteration)) { + PyErr_Clear(); _PyGen_SetStopIterationValue(obj->default_value); } return NULL; @@ -407,6 +408,7 @@ anextawaitable_proxy(anextawaitableobject *obj, char *meth, PyObject *arg) { * exception we replace it with a `StopIteration(default)`, as if * it was the return value of `__anext__()` coroutine. */ + PyErr_Clear(); _PyGen_SetStopIterationValue(obj->default_value); } return NULL;