Running `pytest -v --pyargs openfe openfecli` leaves open too many files

[mikemhenry]

After I installed the linux 1.6.1 single file installer, I wanted to make sure things were working and used: pytest -v --pyargs openfe openfecli to test the install. I ended up with many tests failing due to too many open files (OSError: [Errno 24] Too many open files).

We need to make sure that we don't leave files open. My guess is either our pytest fixtures are the problem or we have some util function that is leaving files handles open (like maybe our pooch stuff for example).

[mikemhenry]

Hint at where the issue is:

Emitted warnings: [ ResourceWarning("unclosed file <_io.TextIOWrapper name='/home/mmh/.cache/openfe/rbfe_results_serial_repeats.tar.gz.untar/rbfe_results_serial_repeats/rbfe_lig_ejm_31_complex_lig_ejm_42_complex/shared_RelativeHybridTopologyProtocolUnit-abb2b104151c45fc8b0993fa0a7ee0af_attempt_0/db.json' mode='r' encoding='UTF-8'>"),

[IAlibay]

@mikemhenry the db.json files not being closed, could that be an openmmforcefields thing? That's where those get generated.

[mikemhenry]

True, I will look there but this happens when running our CLI tests which actually don't use openmmforcefields to do anything, which is why my hunch is with our fixture where these files are unzip and then used

[IAlibay]

Ah apologies, I completely missed that this was coming out of our own tarball's untar-ing.

[mikemhenry]

No it was good shout!