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Python 3.9.6 threading compatibility

See original GitHub issue

We are encountering a high rate of failure with some of our tests after upgrading to Python 3.9.6.

> python3 -m green --run-coverage --cov-config-file my_lib.coveragerc --junit-report my_lib-pytests.xml --include-patterns 'my_lib/*' my_lib
.............................Exception in thread Thread-1:
Traceback (most recent call last):
  File ".pyenv/versions/3.9.6/lib/python3.9/threading.py", line 973, in _bootstrap_inner
    self.run()
  File ".pyenv/versions/3.9.6/lib/python3.9/threading.py", line 910, in run
    self._target(*self._args, **self._kwargs)
  File ".pyenv/versions/3.9.6/lib/python3.9/multiprocessing/pool.py", line 513, in _handle_workers
    cls._maintain_pool(ctx, Process, processes, pool, inqueue,
  File ".pyenv/versions/3.9.6/lib/python3.9/multiprocessing/pool.py", line 337, in _maintain_pool
    Pool._repopulate_pool_static(ctx, Process, processes, pool,
  File ".pyenv/versions/3.9.6/lib/python3.9/multiprocessing/pool.py", line 319, in _repopulate_pool_static
    w = Process(ctx, target=worker,
  File ".pyenv/versions/3.9.6/lib/python3.9/multiprocessing/process.py", line 82, in __init__
    assert group is None, 'group argument must be None for now'
AssertionError: group argument must be None for now
................................................................................................................................................................................................................................................................................................................................................................................................................................................Sending interrupt signal to process
Killing processes
kill finished with exit code 0

This is failing most of the time under docker, not so much under macOS with the same versions of green (3.2.6) and python (3.9.6).

I’m not sure if the issue is with green itself but the stack trace seems to come from green.

Issue Analytics

State:
Created 2 years ago
Comments:14 (6 by maintainers)

Top GitHub Comments

1reaction

CleanCutcommented, Jul 16, 2021

Fixed in Green 3.3.0, which I just released. 🥳 🎈 🎉

1reaction

sodulcommented, Jul 8, 2021

With the help of this post:https://stackoverflow.com/questions/15349997/assertionerror-when-threading-in-python

We found out that the library under test has a subclass of threading.Thread() but with a different signature. We suspect that the code need to be refactored to behave better. It looks like the bug is not in green, but the fact that green get stuck is concerning.

I suppose it got stuck because the code under test got stuck.

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