Alpine errors when running tests in parallel

[Chemaclass]

Q	A
OS	Linux (Alpine)
Shell	bash 3.2
bashunit version	0.17

Summary

Recently, I added parallel testing in bashunit #358 It works pretty well on macOS, however on linux alpine I get these errors (race conditions, I assume) and I after spending hours on it, I was not able to solve it, so I added this note to be aware of it.

Current behavior

Parallel tests are not working properly on linux alpine.

There is currently a feature flag for the parallel feature. See: parallel::is_enabled

function parallel::is_enabled() {
  if env::is_parallel_run_enabled && (check_os::is_macos || check_os::is_ubuntu); then
    return 0
  fi
  return 1
}

Which means, parallel is enabled when the env flag is true BASHUNIT_PARALLEL_RUN=true and is macos or ubuntu.

How to reproduce

You can install and run a docker instance with the bare minimum to run bashunit in your machine using docker:

# from the project itself, using Makefile
make docker/alpine

# then once it's loaded you can run bashunit
./bashunit --simple --parallel

Expected behavior

Parallel tests should work on linux alpine.

[Chemaclass]

Maybe you @skinner-m-c can have some idea why is this error occurring in Alpine but not in macOS 🤔 I thought about mentioning you because you opened #329 and you might have more experience than me with alpine. I've spend hours on this error but I couldn't find a way to deal with it. It's not a blocker anyway, as the feature is working fine in other OS and it's also not interfering with the normal/sync flow.