diff options
Diffstat (limited to 'Lib/asyncio/tasks.py')
| -rw-r--r-- | Lib/asyncio/tasks.py | 30 |
1 files changed, 21 insertions, 9 deletions
diff --git a/Lib/asyncio/tasks.py b/Lib/asyncio/tasks.py index 25a650f..38c2385 100644 --- a/Lib/asyncio/tasks.py +++ b/Lib/asyncio/tasks.py @@ -105,7 +105,7 @@ class Task(futures._PyFuture): # Inherit Python Task implementation else: self._name = str(name) - self._cancel_requested = False + self._num_cancels_requested = 0 self._must_cancel = False self._fut_waiter = None self._coro = coro @@ -198,13 +198,15 @@ class Task(futures._PyFuture): # Inherit Python Task implementation task will be marked as cancelled when the wrapped coroutine terminates with a CancelledError exception (even if cancel() was not called). + + This also increases the task's count of cancellation requests. """ self._log_traceback = False if self.done(): return False - if self._cancel_requested: + self._num_cancels_requested += 1 + if self._num_cancels_requested > 1: return False - self._cancel_requested = True if self._fut_waiter is not None: if self._fut_waiter.cancel(msg=msg): # Leave self._fut_waiter; it may be a Task that @@ -217,14 +219,24 @@ class Task(futures._PyFuture): # Inherit Python Task implementation return True def cancelling(self): - return self._cancel_requested + """Return the count of the task's cancellation requests. + + This count is incremented when .cancel() is called + and may be decremented using .uncancel(). + """ + return self._num_cancels_requested def uncancel(self): - if self._cancel_requested: - self._cancel_requested = False - return True - else: - return False + """Decrement the task's count of cancellation requests. + + This should be used by tasks that catch CancelledError + and wish to continue indefinitely until they are cancelled again. + + Returns the remaining number of cancellation requests. + """ + if self._num_cancels_requested > 0: + self._num_cancels_requested -= 1 + return self._num_cancels_requested def __step(self, exc=None): if self.done(): |