diff options
Diffstat (limited to 'Lib/asyncio/locks.py')
| -rw-r--r-- | Lib/asyncio/locks.py | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/Lib/asyncio/locks.py b/Lib/asyncio/locks.py index d59eb8f..1324eef 100644 --- a/Lib/asyncio/locks.py +++ b/Lib/asyncio/locks.py @@ -158,7 +158,7 @@ class Lock(_ContextManagerMixin): """ def __init__(self, *, loop=None): - self._waiters = collections.deque() + self._waiters = None self._locked = False if loop is not None: self._loop = loop @@ -182,10 +182,13 @@ class Lock(_ContextManagerMixin): This method blocks until the lock is unlocked, then sets it to locked and returns True. """ - if not self._locked and all(w.cancelled() for w in self._waiters): + if (not self._locked and (self._waiters is None or + all(w.cancelled() for w in self._waiters))): self._locked = True return True + if self._waiters is None: + self._waiters = collections.deque() fut = self._loop.create_future() self._waiters.append(fut) @@ -224,6 +227,8 @@ class Lock(_ContextManagerMixin): def _wake_up_first(self): """Wake up the first waiter if it isn't done.""" + if not self._waiters: + return try: fut = next(iter(self._waiters)) except StopIteration: |