This PR reverts gh-93369 and gh-97896 because they've made asyncio tests unstable. After these PRs were merged, random GitHub action jobs of random commits started to fail unrelated tests and test framework methods.
The reverting is necessary because such shrapnel failures are a symptom of some underlying bug that must be found and fixed first.
I had a hope that it's a server overload because we already have extremely rare disc access errors. However, one and a half day passed, and the failures continue to emerge both in PRs and commits.
Affected issue: gh-93357.
First reported in https://github.com/python/cpython/pull/97940#issuecomment-1270004134.
* Revert "gh-93357: Port test cases to IsolatedAsyncioTestCase, part 2 (#97896)"
This reverts commit 09aea94d29.
* Revert "gh-93357: Start porting asyncio server test cases to IsolatedAsyncioTestCase (#93369)"
This reverts commit ce8fc186ac.
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>
The inspect version was not working with unittest.mock.AsyncMock.
The fix introduces special-casing of AsyncMock in
`inspect.iscoroutinefunction` equivalent to the one
performed in `asyncio.iscoroutinefunction`.
Co-authored-by: Łukasz Langa <lukasz@langa.pl>
test_asyncio, test_logging, test_socket and test_socketserver now
create AF_UNIX domains in the current directory to no longer fail
with OSError("AF_UNIX path too long") if the temporary directory (the
TMPDIR environment variable) is too long.
Modify the following tests to use create_unix_domain_name():
* test_asyncio
* test_logging
* test_socket
* test_socketserver
test_asyncio.utils: remove unused time import.
run_until() of test.test_asyncio.utils now uses an exponential sleep
delay (max: 1 second), rather than a fixed delay of 1 ms. Similar
design than support.sleeping_retry() wait strategy that applies
exponential backoff.
* Replace time.sleep(0.010) with sleeping_retry() to
use an exponential sleep.
* support.wait_process(): reuse sleeping_retry().
* _test_eintr: remove unused variables.
On slow buildbot workers, some test_ssl tests fail randomly because
of short timeout (30 seconds). Use support.LONG_TIMEOUT instead which
is longer and also adjusted (by regrtest --timeout option) on
buildbot workers known to be slow.
One more thing that can help prevent people from using `preexec_fn`.
Also adds conditional skips to two tests exposing ASAN flakiness on the Ubuntu 20.04 Address Sanitizer Github CI system. When that build is run on more modern systems the "problem" does not show up. It seems ASAN implementation related.
Co-authored-by: Zackery Spytz <zspytz@gmail.com>
Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>
The existing event loop `start_tls()` method is not sufficient for
connections using the streams API. The existing StreamReader works
because the new transport passes received data to the original protocol.
The StreamWriter must then write data to the new transport, and the
StreamReaderProtocol must be updated to close the new transport
correctly.
The new StreamWriter `start_tls()` updates itself and the reader
protocol to the new SSL transport.
Co-authored-by: Ian Good <icgood@gmail.com>
After a long deliberation we ended up feeling that the message argument for Future.cancel(), added in 3.9, was a bad idea, so we're deprecating it in 3.11 and plan to remove it in 3.13.
- Add requires_fork and requires_subprocess to more tests
- Skip extension import tests if dlopen is not available
- Don't assume that _testcapi is a shared extension
- Skip a lot of socket tests that don't work on Emscripten
- Skip mmap tests, mmap emulation is incomplete
- venv does not work yet
- Cannot get libc from executable
The "entire" test suite is now passing on Emscripten with EMSDK from git head (91 suites are skipped).
GH-30297 removed a duplicate `from test import support` statement from `test_asyncio.test_sslproto`. However, in between that PR being filed and it being merged, GH-31275 removed the _other_ `from test import support` statement. This means that `support` is now undefined in `test_asyncio.test_sslproto`, causing the CI to fail on all platforms for all PRS.
Example:
async with asyncio.timeout(5):
await some_task()
Will interrupt the await and raise TimeoutError if some_task() takes longer than 5 seconds.
Co-authored-by: Guido van Rossum <guido@python.org>
Also from the _asyncio C accelerator module,
and adjust one test that the change caused to fail.
For more discussion see the discussion starting here:
https://github.com/python/cpython/pull/31394#issuecomment-1053545331
(Basically, @asvetlov proposed to return False from cancel()
when there is already a pending cancellation, and I went along,
even though it wasn't necessary for the task group implementation,
and @agronholm has come up with a counterexample that fails
because of this change. So now I'm changing it back to the old
semantics (but still bumping the counter) until we can have a
proper discussion about this.)
* Remove task group names (for now)
We're not sure that they are needed, and once in the code
we would never be able to get rid of them.
Yury wrote:
> Ideally, there should be a way for someone to build a "trace"
> of taskgroups/task leading to the current running task.
> We could do that using contextvars, but I'm not sure we should
> do that in 3.11.
* Pass optional name on to task in create_task()
* Remove a bunch of unused stuff
asyncio/taskgroups.py is an adaptation of taskgroup.py from EdgeDb, with the following key changes:
- Allow creating new tasks as long as the last task hasn't finished
- Raise [Base]ExceptionGroup (directly) rather than TaskGroupError deriving from MultiError
- Instead of monkey-patching the parent task's cancel() method,
add a new public API to Task
The Task class has a new internal flag, `_cancel_requested`, which is set when `.cancel()` is called successfully. The `.cancelling()` method returns the value of this flag. Further `.cancel()` calls while this flag is set return False. To reset this flag, call `.uncancel()`.
Thus, a Task that catches and ignores `CancelledError` should call `.uncancel()` if it wants to be cancellable again; until it does so, it is deemed to be busy with uninterruptible cleanup.
This new Task API helps solve the problem where TaskGroup needs to distinguish between whether the parent task being cancelled "from the outside" vs. "from inside".
Co-authored-by: Yury Selivanov <yury@edgedb.com>
Co-authored-by: Andrew Svetlov <andrew.svetlov@gmail.com>
Due to significant security concerns, the reuse_address parameter of
asyncio.loop.create_datagram_endpoint, deprecated in Python 3.9, is
now removed. This is because of the behavior of the socket option
SO_REUSEADDR in UDP.
Co-authored-by: Łukasz Langa <lukasz@langa.pl>
Guido van Rossum