asyncio: Improve canceled timer handles cleanup. Closes issue #22448.
Patch by Joshua Moore-Oliva.
diff --git a/Lib/asyncio/events.py b/Lib/asyncio/events.py
index b7cc351..806218f 100644
--- a/Lib/asyncio/events.py
+++ b/Lib/asyncio/events.py
@@ -105,14 +105,15 @@
return '<%s>' % ' '.join(info)
def cancel(self):
- self._cancelled = True
- if self._loop.get_debug():
- # Keep a representation in debug mode to keep callback and
- # parameters. For example, to log the warning "Executing <Handle
- # ...> took 2.5 second"
- self._repr = repr(self)
- self._callback = None
- self._args = None
+ if not self._cancelled:
+ self._cancelled = True
+ if self._loop.get_debug():
+ # Keep a representation in debug mode to keep callback and
+ # parameters. For example, to log the warning
+ # "Executing <Handle...> took 2.5 second"
+ self._repr = repr(self)
+ self._callback = None
+ self._args = None
def _run(self):
try:
@@ -134,7 +135,7 @@
class TimerHandle(Handle):
"""Object returned by timed callback registration methods."""
- __slots__ = ['_when']
+ __slots__ = ['_scheduled', '_when']
def __init__(self, when, callback, args, loop):
assert when is not None
@@ -142,6 +143,7 @@
if self._source_traceback:
del self._source_traceback[-1]
self._when = when
+ self._scheduled = False
def _repr_info(self):
info = super()._repr_info()
@@ -180,6 +182,11 @@
equal = self.__eq__(other)
return NotImplemented if equal is NotImplemented else not equal
+ def cancel(self):
+ if not self._cancelled:
+ self._loop._timer_handle_cancelled(self)
+ super().cancel()
+
class AbstractServer:
"""Abstract server returned by create_server()."""
@@ -238,6 +245,10 @@
# Methods scheduling callbacks. All these return Handles.
+ def _timer_handle_cancelled(self, handle):
+ """Notification that a TimerHandle has been cancelled."""
+ raise NotImplementedError
+
def call_soon(self, callback, *args):
return self.call_later(0, callback, *args)