Internal pytest / coverage error

[fjetter]

We're seeing occasionally an internal pytest error in CI that goes back to coveragepy. This issue is merely for documentation purposes since the issue was already fixed upstream

nedbat/coveragepy#1522
https://github.com/nedbat/coveragepy/releases/tag/7.0.3

Error reported was

INTERNALERROR> Traceback (most recent call last):
INTERNALERROR>   File "/usr/share/miniconda3/envs/dask-distributed/lib/python3.9/site-packages/_pytest/main.py", line 270, in wrap_session
INTERNALERROR>     session.exitstatus = doit(config, session) or 0
INTERNALERROR>   File "/usr/share/miniconda3/envs/dask-distributed/lib/python3.9/site-packages/_pytest/main.py", line 324, in _main
INTERNALERROR>     config.hook.pytest_runtestloop(session=session)
INTERNALERROR>   File "/usr/share/miniconda3/envs/dask-distributed/lib/python3.9/site-packages/pluggy/_hooks.py", line 265, in __call__
INTERNALERROR>     return self._hookexec(self.name, self.get_hookimpls(), kwargs, firstresult)
INTERNALERROR>   File "/usr/share/miniconda3/envs/dask-distributed/lib/python3.9/site-packages/pluggy/_manager.py", line 80, in _hookexec
INTERNALERROR>     return self._inner_hookexec(hook_name, methods, kwargs, firstresult)
INTERNALERROR>   File "/usr/share/miniconda3/envs/dask-distributed/lib/python3.9/site-packages/pluggy/_callers.py", line 55, in _multicall
INTERNALERROR>     gen.send(outcome)
INTERNALERROR>   File "/usr/share/miniconda3/envs/dask-distributed/lib/python3.9/site-packages/pytest_cov/plugin.py", line 297, in pytest_runtestloop
INTERNALERROR>     self.cov_controller.finish()
INTERNALERROR>   File "/usr/share/miniconda3/envs/dask-distributed/lib/python3.9/site-packages/pytest_cov/engine.py", line 44, in ensure_topdir_wrapper
INTERNALERROR>     return meth(self, *args, **kwargs)
INTERNALERROR>   File "/usr/share/miniconda3/envs/dask-distributed/lib/python3.9/site-packages/pytest_cov/engine.py", line 242, in finish
INTERNALERROR>     self.cov.stop()
INTERNALERROR>   File "/usr/share/miniconda3/envs/dask-distributed/lib/python3.9/site-packages/coverage/control.py", line 791, in combine
INTERNALERROR>     combine_parallel_data(
INTERNALERROR>   File "/usr/share/miniconda3/envs/dask-distributed/lib/python3.9/site-packages/coverage/data.py", line 158, in combine_parallel_data
INTERNALERROR>     new_data.read()
INTERNALERROR>   File "/usr/share/miniconda3/envs/dask-distributed/lib/python3.9/site-packages/coverage/sqldata.py", line 815, in read
INTERNALERROR>     with self._connect():
INTERNALERROR>   File "/usr/share/miniconda3/envs/dask-distributed/lib/python3.9/site-packages/coverage/sqldata.py", line 342, in _connect
INTERNALERROR>     self._open_db()
INTERNALERROR>   File "/usr/share/miniconda3/envs/dask-distributed/lib/python3.9/site-packages/coverage/sqldata.py", line 285, in _open_db
INTERNALERROR>     self._read_db()
INTERNALERROR>   File "/usr/share/miniconda3/envs/dask-distributed/lib/python3.9/site-packages/coverage/sqldata.py", line 302, in _read_db
INTERNALERROR>     assert row is not None
INTERNALERROR> AssertionError

https://github.com/dask/distributed/actions/runs/3839276483/jobs/6536815225