diff options
Diffstat (limited to 'Lib/asyncio/tasks.py')
-rw-r--r-- | Lib/asyncio/tasks.py | 50 |
1 files changed, 33 insertions, 17 deletions
diff --git a/Lib/asyncio/tasks.py b/Lib/asyncio/tasks.py index 825e91f5594..fbd5c39a7c5 100644 --- a/Lib/asyncio/tasks.py +++ b/Lib/asyncio/tasks.py @@ -386,19 +386,13 @@ else: Task = _CTask = _asyncio.Task -def create_task(coro, *, name=None, context=None): +def create_task(coro, **kwargs): """Schedule the execution of a coroutine object in a spawn task. Return a Task object. """ loop = events.get_running_loop() - if context is None: - # Use legacy API if context is not needed - task = loop.create_task(coro, name=name) - else: - task = loop.create_task(coro, name=name, context=context) - - return task + return loop.create_task(coro, **kwargs) # wait() and as_completed() similar to those in PEP 3148. @@ -914,6 +908,25 @@ def gather(*coros_or_futures, return_exceptions=False): return outer +def _log_on_exception(fut): + if fut.cancelled(): + return + + exc = fut.exception() + if exc is None: + return + + context = { + 'message': + f'{exc.__class__.__name__} exception in shielded future', + 'exception': exc, + 'future': fut, + } + if fut._source_traceback: + context['source_traceback'] = fut._source_traceback + fut._loop.call_exception_handler(context) + + def shield(arg): """Wait for a future, shielding it from cancellation. @@ -959,14 +972,11 @@ def shield(arg): else: cur_task = None - def _inner_done_callback(inner, cur_task=cur_task): - if cur_task is not None: - futures.future_discard_from_awaited_by(inner, cur_task) + def _clear_awaited_by_callback(inner): + futures.future_discard_from_awaited_by(inner, cur_task) + def _inner_done_callback(inner): if outer.cancelled(): - if not inner.cancelled(): - # Mark inner's result as retrieved. - inner.exception() return if inner.cancelled(): @@ -978,10 +988,16 @@ def shield(arg): else: outer.set_result(inner.result()) - def _outer_done_callback(outer): if not inner.done(): inner.remove_done_callback(_inner_done_callback) + # Keep only one callback to log on cancel + inner.remove_done_callback(_log_on_exception) + inner.add_done_callback(_log_on_exception) + + if cur_task is not None: + inner.add_done_callback(_clear_awaited_by_callback) + inner.add_done_callback(_inner_done_callback) outer.add_done_callback(_outer_done_callback) @@ -1030,9 +1046,9 @@ def create_eager_task_factory(custom_task_constructor): used. E.g. `loop.set_task_factory(asyncio.eager_task_factory)`. """ - def factory(loop, coro, *, name=None, context=None): + def factory(loop, coro, *, eager_start=True, **kwargs): return custom_task_constructor( - coro, loop=loop, name=name, context=context, eager_start=True) + coro, loop=loop, eager_start=eager_start, **kwargs) return factory |