diff options
Diffstat (limited to 'Lib/asyncio/tasks.py')
| -rw-r--r-- | Lib/asyncio/tasks.py | 22 |
1 files changed, 12 insertions, 10 deletions
diff --git a/Lib/asyncio/tasks.py b/Lib/asyncio/tasks.py index 63cbcda32f..e6389d82bd 100644 --- a/Lib/asyncio/tasks.py +++ b/Lib/asyncio/tasks.py @@ -220,9 +220,9 @@ class Task(futures.Future): self._must_cancel = True return True - def _step(self, value=None, exc=None): + def _step(self, exc=None): assert not self.done(), \ - '_step(): already done: {!r}, {!r}, {!r}'.format(self, value, exc) + '_step(): already done: {!r}, {!r}'.format(self, exc) if self._must_cancel: if not isinstance(exc, futures.CancelledError): exc = futures.CancelledError() @@ -231,12 +231,14 @@ class Task(futures.Future): self._fut_waiter = None self.__class__._current_tasks[self._loop] = self - # Call either coro.throw(exc) or coro.send(value). + # Call either coro.throw(exc) or coro.send(None). try: - if exc is not None: - result = coro.throw(exc) + if exc is None: + # We use the `send` method directly, because coroutines + # don't have `__iter__` and `__next__` methods. + result = coro.send(None) else: - result = coro.send(value) + result = coro.throw(exc) except StopIteration as exc: self.set_result(exc.value) except futures.CancelledError as exc: @@ -258,7 +260,7 @@ class Task(futures.Future): self._must_cancel = False else: self._loop.call_soon( - self._step, None, + self._step, RuntimeError( 'yield was used instead of yield from ' 'in task {!r} with {!r}'.format(self, result))) @@ -268,7 +270,7 @@ class Task(futures.Future): elif inspect.isgenerator(result): # Yielding a generator is just wrong. self._loop.call_soon( - self._step, None, + self._step, RuntimeError( 'yield was used instead of yield from for ' 'generator in task {!r} with {}'.format( @@ -276,7 +278,7 @@ class Task(futures.Future): else: # Yielding something else is an error. self._loop.call_soon( - self._step, None, + self._step, RuntimeError( 'Task got bad yield: {!r}'.format(result))) finally: @@ -288,7 +290,7 @@ class Task(futures.Future): future.result() except Exception as exc: # This may also be a cancellation. - self._step(None, exc) + self._step(exc) else: # Don't pass the value of `future.result()` explicitly, # as `Future.__iter__` and `Future.__await__` don't need it. |