https://github.com/python/cpython/commit/9d05428b29508873fb26832eea5d17e0e8de60df commit: 9d05428b29508873fb26832eea5d17e0e8de60df branch: main author: Timofei Ivankov <[email protected]> committer: kumaraditya303 <[email protected]> date: 2026-11-10T16:58:27+05:30 summary:
gh-161083: Fix stale awaited_by nodes on invalid asyncio.gather() arguments (#161084) Co-authored-by: Kumar Aditya <[email protected]> files: A Misc/NEWS.d/next/Library/2026-11-01-19-38-33.gh-issue-161083.PM21lv.rst M Lib/asyncio/tasks.py M Lib/test/test_asyncio/test_tasks.py diff --git a/Lib/asyncio/tasks.py b/Lib/asyncio/tasks.py index 6c8d7cbbda64407..70da1e25ebaf081 100644 --- a/Lib/asyncio/tasks.py +++ b/Lib/asyncio/tasks.py @@ -926,8 +926,6 @@ def _done_callback(fut, cur_task=cur_task): if fut.done(): done_futs.append(fut) else: - if cur_task is not None: - futures.future_add_to_awaited_by(fut, cur_task) fut.add_done_callback(_done_callback) else: @@ -937,6 +935,11 @@ def _done_callback(fut, cur_task=cur_task): children.append(fut) outer = _GatheringFuture(children, loop=loop) + # Add the awaited-by edges only after all arguments are validated + if cur_task is not None and len(done_futs) < nfuts: + for fut in arg_to_fut.values(): + if not fut.done(): + futures.future_add_to_awaited_by(fut, cur_task) # Run done callbacks after GatheringFuture created so any post-processing # can be performed at this point # optimization: in the special case that *all* futures finished eagerly, diff --git a/Lib/test/test_asyncio/test_tasks.py b/Lib/test/test_asyncio/test_tasks.py index f16815474e2d196..ac4856bd7a64c84 100644 --- a/Lib/test/test_asyncio/test_tasks.py +++ b/Lib/test/test_asyncio/test_tasks.py @@ -1328,6 +1328,18 @@ async def coro(): self.loop.run_until_complete(self.new_task(self.loop, coro())) + def test_gather_invalid_arg_does_not_add_awaited_by(self): + async def coro(): + task = self.new_task(self.loop, asyncio.sleep(0)) + try: + with self.assertRaises(TypeError): + asyncio.gather(task, None) + self.assertFalse(task._asyncio_awaited_by) + finally: + await task + + self.loop.run_until_complete(self.new_task(self.loop, coro())) + def test_gather_discards_awaited_by_for_pending(self): # gh-157213: a child outliving gather() must lose the awaited-by edge async def fail(): diff --git a/Misc/NEWS.d/next/Library/2026-11-01-19-38-33.gh-issue-161083.PM21lv.rst b/Misc/NEWS.d/next/Library/2026-11-01-19-38-33.gh-issue-161083.PM21lv.rst new file mode 100644 index 000000000000000..98b3ea827276518 --- /dev/null +++ b/Misc/NEWS.d/next/Library/2026-11-01-19-38-33.gh-issue-161083.PM21lv.rst @@ -0,0 +1,2 @@ +Fix stale task nodes left by :func:`asyncio.gather` when argument validation +fails. Patch by Timofei Ivankov _______________________________________________ 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]
