diff --git a/Lib/asyncio/test_utils.py b/Lib/asyncio/test_utils.py index 6eedc583dba..8cee95b84f9 100644 --- a/Lib/asyncio/test_utils.py +++ b/Lib/asyncio/test_utils.py @@ -416,6 +416,10 @@ class TestCase(unittest.TestCase): def tearDown(self): events.set_event_loop(None) + # Detect CPython bug #23353: ensure that yield/yield-from is not used + # in an except block of a generator + self.assertEqual(sys.exc_info(), (None, None, None)) + @contextlib.contextmanager def disable_logger(): diff --git a/Lib/asyncio/unix_events.py b/Lib/asyncio/unix_events.py index 1fc39abe09c..75e7c9ccadd 100644 --- a/Lib/asyncio/unix_events.py +++ b/Lib/asyncio/unix_events.py @@ -186,10 +186,18 @@ class _UnixSelectorEventLoop(selector_events.BaseSelectorEventLoop): self._child_watcher_callback, transp) try: yield from waiter - except: + except Exception as exc: + # Workaround CPython bug #23353: using yield/yield-from in an + # except block of a generator doesn't clear properly + # sys.exc_info() + err = exc + else: + err = None + + if err is not None: transp.close() yield from transp._wait() - raise + raise err return transp diff --git a/Lib/asyncio/windows_events.py b/Lib/asyncio/windows_events.py index c4bffc47346..f311e463155 100644 --- a/Lib/asyncio/windows_events.py +++ b/Lib/asyncio/windows_events.py @@ -373,10 +373,17 @@ class ProactorEventLoop(proactor_events.BaseProactorEventLoop): **kwargs) try: yield from waiter - except: + except Exception as exc: + # Workaround CPython bug #23353: using yield/yield-from in an + # except block of a generator doesn't clear properly sys.exc_info() + err = exc + else: + err = None + + if err is not None: transp.close() yield from transp._wait() - raise + raise err return transp