diff --git a/Lib/asyncio/taskgroups.py b/Lib/asyncio/taskgroups.py index 3ca65062efd272..097b4864f7ab98 100644 --- a/Lib/asyncio/taskgroups.py +++ b/Lib/asyncio/taskgroups.py @@ -54,21 +54,22 @@ async def __aenter__(self): async def __aexit__(self, et, exc, tb): self._exiting = True - propagate_cancellation_error = None if (exc is not None and self._is_base_error(exc) and self._base_error is None): self._base_error = exc - if et is not None: - if et is exceptions.CancelledError: - if self._parent_cancel_requested and not self._parent_task.uncancel(): - # Do nothing, i.e. swallow the error. - pass - else: - propagate_cancellation_error = exc + propagate_cancellation_error = \ + exc if et is exceptions.CancelledError else None + if self._parent_cancel_requested: + # If this flag is set we *must* call uncancel(). + if self._parent_task.uncancel() == 0: + # If there are no pending cancellations left, + # don't propagate CancelledError. + propagate_cancellation_error = None + if et is not None: if not self._aborting: # Our parent task is being cancelled: #