$BATS_MOCK_TMPDIR issue from #19 is not settled

[KlfJoat]

Hi. I submitted PR #19 to use $BATS_RUN_TMPDIR for $BATS_MOCK_TMPDIR. That fixes accidentally not unstubbing. But with or without it, I realized since submitting the PR that another issue remains.

If I run a large suite of Bats tests (say, >1,000) in job parallel mode, the stubs interfere with each other and cause errors since they're all set in the run tmpdir and have no separation from each other.

I have taken to patching in $BATS_FILE_TMPDIR instead. Then at least I can disable parallelization in the individual Bats files where I use bats-mock (with export BATS_NO_PARALLELIZE_WITHIN_FILE=true) and still get parallelization across the other test files.

The other option is to set $BATS_MOCK_TMPDIR to $BATS_TEST_TMPDIR... however, that prevents people from doing a stub in the file setup() function and unstub in the file teardown() function. But it allows for parallelization within Bats test files that use bats-mock.

I prefer $BATS_FILE_TMPDIR and use sed to patch it in bc of the control I retain in the current big bash project I'm working on. But the next project might mean that I'm patching in $BATS_TEST_TMPDIR due to high bats-mock usage and need for parallelization.

There doesn't seem to be a good answer here, only a design decision to be made and documentation on the limitations/requirements. As such, I defer to you as owners.