Possible race condition when using `AuditSpinner`

[i386x]

Bug description

With --progress-spinner being on, either spinner text or memory-stored logs appears on the terminal, but not both.

Examples:

• spinner message, no logs:

  py310: commands[0]> python -m pip_audit -S .
  - Collecting inputs
  py310: exit 1 (0.51 seconds) /home/jkucera/development/upstream/vutils-validator> python -m pip_audit -S . pid=47412
  

• no spinner message, logs:

  py310: commands[0]> python -m pip_audit -S .
  ERROR:pip_audit._cli:pyproject file pyproject.toml does not contain `project` section
  py310: exit 1 (0.51 seconds) /home/jkucera/development/upstream/vutils-validator> python -m pip_audit -S . pid=47276
  

As a workaround, --progress-spinner need to be set to off:

py310: commands[0]> python -m pip_audit --progress-spinner off -S .
ERROR:pip_audit._cli:pyproject file pyproject.toml does not contain `project` section
py310: exit 1 (0.50 seconds) /home/jkucera/development/upstream/vutils-validator> python -m pip_audit --progress-spinner off -S . pid=47455

Reproduction steps

1. Add python -m pip_audit -S . to your tox.ini file.
2. Remove [project] section from your pyproject.toml file.
3. Run tox multiple times and watch its behavior.

Expected behavior

Both spinner and logs should be displayed on the terminal.

Screenshots and logs

See examples above.

Platform information

• OS name and version: Fedora Linux 37 (Workstation Edition)
• pip-audit version (pip-audit -V): pip-audit 2.7.1
• Python version (python -V or python3 -V): Python 3.10.12
• pip version (pip -V or pip3 -V): pip 23.2.1
• tox version: 3.28.0

[woodruffw]

Thanks for the report @i386x!

Hmm, this is odd -- we should always spit out the logs unconditionally after the spinner concludes. I haven't seen this behavior outside of being wrapped by a runner like tox, so I wonder if this is a case of lossy wrapping on the child process's stdout/stderr.

That's just a random guess though; I'll triage more later this week.

[woodruffw]

I'll keep experimenting here, but I've been unable to reproduce this outside of a wrapper (I'll try tox later today).

[woodruffw]

I've been unable to reproduce this. @i386x, are you able to create a reproducer that doesn't depend on tox?

[i386x]

I will try.