Incompatible with parallel mode

[rpkilby]

Hi @ryanhiebert. I've been working on tox-factor, which is a stripped down version of tox-travis's envlist matching feature (e.g. invoked as tox -f py37 to match all py37-* testenvs, instead of matching from Travis environment factors).

Anyway, like tox-travis, tox-factor ultimately works by setting the config.envlist in the tox_configure hook. However, this overrides the parallelized tox subprocesses, which have their testenv set via the TOX_PARALLEL_ENV env var. The fix is to ensure env matching only performs in the main tox process, not the parallelized subprocesses. For reference:

• original issue: Incompatible with tox --parallel rpkilby/tox-factor#3
• pull request: Parallel mode compat rpkilby/tox-factor#4
• tox parallel testing issue: tox parallelized subprocesses should remove TOX_PARALLEL_ENV from passenv tox#1275

[ryanhiebert]

Thanks! I've been wondering how that project was going.