asyncio.TaskGroup and asyncio.Timeout classes now raise proper RuntimeError
if they are improperly used.
* When they are used without entering the context manager.
* When they are used after finishing.
* When the context manager is entered more than once (simultaneously or
sequentially).
* If there is no current task when entering the context manager.
They now remain in a consistent state after an exception is thrown,
so subsequent operations can be performed correctly (if they are allowed).
Co-authored-by: James Hilton-Balfe <gobot1234yt@gmail.com>
Replace harcoded sleep of 500 ms with synchronization using a pipe.
Fix also Process._feed_stdin(): catch also BrokenPipeError on
stdin.write(input), not only on stdin.drain().
SubprocessProtocol process_exited() method can be called before
pipe_data_received() and pipe_connection_lost() methods. Document it
and adapt the test for that.
Revert commit 282edd7b2a.
_child_watcher_callback() calls immediately _process_exited(): don't
add an additional delay with call_soon(). The reverted change didn't
make _process_exited() more determistic: it can still be called
before pipe_connection_lost() for example.
Co-authored-by: Davide Rizzo <sorcio@gmail.com>
subprocess's communicate(None) closes stdin of the child process, after
sending no (extra) data. Make asyncio variant do the same.
This fixes issues with processes that waits for EOF on stdin before
continuing.
Also use `raise TimeOut from <CancelledError instance>` so that the CancelledError is set
in the `__cause__` field rather than in the `__context__` field.
Co-authored-by: Guido van Rossum <gvanrossum@gmail.com>
Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>
Partially revert changes made in GH-93453.
asyncio.DefaultEventLoopPolicy.get_event_loop() now emits a
DeprecationWarning and creates and sets a new event loop instead of
raising a RuntimeError if there is no current event loop set.
Co-authored-by: Guido van Rossum <gvanrossum@gmail.com>
asyncio.get_event_loop() now always return either running event loop or
the result of get_event_loop_policy().get_event_loop() call. The latter
should now raise an RuntimeError if no current event loop was set
instead of creating and setting a new event loop.
It affects also a number of asyncio functions and constructors which
call get_event_loop() implicitly: ensure_future(), shield(), gather(),
etc.
DeprecationWarning is no longer emitted if there is no running event loop but
the current event loop was set.
Co-authored-by: Łukasz Langa <lukasz@langa.pl>
It was a no-op when used as recommended (after close()).
I had to debug one test (test__sock_sendfile_native_failure) --
the cleanup sequence for the test fixture was botched.
Hopefully that's not a portend of problems in user code --
this has never worked so people may well be doing this wrong. :-(
Co-authored-by: kumar aditya
Alas, warnings.catch_warnings() has global scope, not thread scope, so this is still not perfect, but it reduces the time during which warnings are ignored. Better solution welcome.
This is the next step for deprecating child watchers.
Until we've removed the API completely we have to use it, so this PR is mostly suppressing a lot of warnings when using the API internally.
Once the child watcher API is totally removed, the two child watcher implementations we actually use and need (Pidfd and Thread) will be turned into internal helpers.
There is no reason for this watcher to be attached to any particular loop.
This should make it safe to use regardless of the lifetime of the event loop running in the main thread
(relative to other loops).
Co-authored-by: Yury Selivanov <yury@edgedb.com>
Co-authored-by: Jelle Zijlstra <jelle.zijlstra@gmail.com>
Ensure that the event loop's `_thread_id` attribute and the asyncgen hooks set by `sys.set_asyncgen_hooks()` are always restored no matter where a KeyboardInterrupt exception is raised.
The main problem was that an unluckily timed task cancellation could cause
the semaphore to be stuck. There were also doubts about strict FIFO ordering
of tasks allowed to pass.
The Semaphore implementation was rewritten to be more similar to Lock.
Many tests for edge cases (including cancellation) were added.
This reverts commit 0587810698.
Reason: This broke buildbots (some warnings added by that commit are turned to errors in the SSL buildbot).
Repro: ./python Lib/test/ssltests.py
Warn on loop initialization, when setting the wakeup fd disturbs a previously set wakeup fd, and on loop closing, when upon resetting the wakeup fd, we find it has been changed by someone else.
When a task catches CancelledError and raises some other error,
the other error should not silently be suppressed.
Any scenario where a task crashes in cleanup upon cancellation
will now result in an ExceptionGroup wrapping the crash(es)
instead of propagating CancelledError and ignoring the side errors.
NOTE: This represents a change in behavior (hence the need to
change several tests). But it is only an edge case.
Co-authored-by: Thomas Grainger <tagrain@gmail.com>
Once the task group is shutting down, it should not be possible to create a new task.
Here "shutting down" means `self._aborting` is set, indicating that at least one task
has failed and we have cancelled all others.
Co-authored-by: Łukasz Langa <lukasz@langa.pl>
Serhiy Storchaka
Bar Harel
Thomas Grainger
Russell Keith-Magee
J. Nick Koston
Kristján Valur Jónsson
Tom Gillespie
Alex Waygood
Victor Stinner
Nikita Sobolev
Kumar Aditya
Chris Brett
Andrew Geng
James Webber
Kumar Aditya
Jay
Guido van Rossum
Sam Bull
Jacob Bower
Itamar Ostricher
Marek Marczykowski-Górecki
Itayazolay
Ali-Akber Saifee
JosephSBoyle
Jan Gosmann
beavailable
Richard Kojedzinszky
DarioDaF
Dong Uk, Kang
Carlo
Ken Jin
Tony Solomonik
Christoph Hamsen
hetmankp
Łukasz Langa
Cyker Way
Michel Hidalgo
Hendrik Makait
Pamela Fox
Kirill
Yury Selivanov