RuntimeWarning when running AsyncHandlerRequestTests.test_unawaited_response.

[Deep Sukhwani]

Steps to reproduce:

• Use a Python virtualenv with Python 3.7.7 / Python 3.8.2
• Install requirements - from Django root with latest master (of the the date of this issue): cd tests && pip install -r requirements/py3.txt
• Run tests export DJANGO_TEST_PROCESSES=1; export OBJC_DISABLE_INITIALIZE_FORK_SAFETY=YES; ./runtests.py
• This is reproducible in django-docker-box using Python 3.7 and Python 3.8, verified as follows:

PYTHON_VERSION=3.7 docker-compose run --rm sqlite
PYTHON_VERSION=3.8 docker-compose run --rm sqlite

Notes:

• To ensure this is not happening due to parallelization, I had set export DJANGO_TEST_PROCESSES=1; while triggering ./runtests.py

Warning text:

Exception ignored in: <coroutine object sleep at 0x130ef1320>
Traceback (most recent call last):
  File "/Users/ds/.pyenv/versions/3.7.7/lib/python3.7/warnings.py", line 518, in _warn_unawaited_coroutine
    warn(msg, category=RuntimeWarning, stacklevel=2, source=coro)
RuntimeWarning: coroutine 'sleep' was never awaited

Other Observations:

• This warning was not observed when running tests with Python 3.6, verified on macOS and django-docker-box. For django-docker-box the tests were run using: PYTHON_VERSION=3.6 docker-compose run --rm sqlite

[Mariusz Felisiak]

handlers.tests.AsyncHandlerRequestTests.test_unawaited_response raises this warning because it tests unawaited coroutine. I agree that we can suppress this warning.

[Mark]

Replying to Mahdi Sadeghzadeh Ghamsary:

How are you going with this? Otherwise I would gladly take a shot a this

[Mark]

​PR

[GitHub <noreply@…>]

In 590957a:

Fixed #31407 -- Adjusted test to avoid coroutine never awaited warning.

[Mariusz Felisiak]

With this fix we have the same warning but after all tests, e.g.

./runtests.py handlers --parallel=1

Testing against Django installed in 'django/django'
Creating test database for alias 'default'...
System check identified no issues (0 silenced).
.............................
----------------------------------------------------------------------
Ran 29 tests in 0.377s

OK
Destroying test database for alias 'default'...
Exception ignored in: <coroutine object sleep at 0x7fc660d70040>
RuntimeWarning: coroutine 'sleep' was never awaited

[Carlton Gibson]

OK, I will take another look. (I had this clearing up OK the other day so...) Thanks Mariusz.

[Carlton Gibson]

​New PR

[Mariusz Felisiak]

​PR

[Carlton Gibson <carlton@…>]

In ed274a4a:

Fixed #31407 -- Fixed unawaited coroutine warning for Python 3.8+.

Co-authored-by: Mark Korput <dr.theman@…>

[Carlton Gibson <carlton@…>]

In 236e6cb5:

Refs #31407 -- Handled potential exception in test cleanup.

The test view may not be called when running the tests with
--parallel=2 or greater. Catch the AttributeError for this case.