diff options
| -rw-r--r-- | Lib/asyncio/coroutines.py | 8 | ||||
| -rw-r--r-- | Lib/test/test_asyncio/test_pep492.py | 20 |
2 files changed, 27 insertions, 1 deletions
diff --git a/Lib/asyncio/coroutines.py b/Lib/asyncio/coroutines.py index e11b21b097..3a92c7d755 100644 --- a/Lib/asyncio/coroutines.py +++ b/Lib/asyncio/coroutines.py @@ -140,7 +140,13 @@ class CoroWrapper: if compat.PY35: - __await__ = __iter__ # make compatible with 'await' expression + def __await__(self): + cr_await = getattr(self.gen, 'cr_await', None) + if cr_await is not None: + raise RuntimeError( + "Cannot await on coroutine {!r} while it's " + "awaiting for {!r}".format(self.gen, cr_await)) + return self @property def gi_yieldfrom(self): diff --git a/Lib/test/test_asyncio/test_pep492.py b/Lib/test/test_asyncio/test_pep492.py index 41e1b8a9e0..404a7489ae 100644 --- a/Lib/test/test_asyncio/test_pep492.py +++ b/Lib/test/test_asyncio/test_pep492.py @@ -203,6 +203,26 @@ class CoroutineTests(BaseTest): self.loop.run_until_complete(runner()) + def test_double_await(self): + async def afunc(): + await asyncio.sleep(0.1, loop=self.loop) + + async def runner(): + coro = afunc() + t = asyncio.Task(coro, loop=self.loop) + try: + await asyncio.sleep(0, loop=self.loop) + await coro + finally: + t.cancel() + + self.loop.set_debug(True) + with self.assertRaisesRegex( + RuntimeError, + r'Cannot await.*test_double_await.*\bafunc\b.*while.*\bsleep\b'): + + self.loop.run_until_complete(runner()) + if __name__ == '__main__': unittest.main() |