Name ".tox" should not be allowed in "envlist"

[sinoroc]

• tox 3.20.0

---

Name .tox should not be allowed in envlist.

Apparently there are safe guards in code, so that when isolated_build is set in tox.ini then adding .package to envlist and/or running tox -e .package throws an exception relatively early on:

tox.exception.ConfigError: ConfigError: isolated_build_env .package cannot be part of envlist

There doesn't seem to be such safe guards for the case where requires is set in tox.ini and .tox is added to envlist.

---

[tox]
envlist =
    .tox
requires =
    wheel
skipsdist = True

[testenv]
commands =
    python -V

$ rm -rf .tox && tox
.tox create: /home/sinoroc/workspace/dot-tox/.tox/.tox
.tox installdeps: wheel, tox >= 3.20.0
.tox recreate: /home/sinoroc/workspace/dot-tox/.tox/.tox
ERROR: invocation failed (exit code 2), logfile: /home/sinoroc/workspace/dot-tox/.tox/.tox/log/.tox-0.log
=============================================== log start ===============================================

================================================ log end ================================================
ERROR: InvocationError for command /home/sinoroc/workspace/dot-tox/.tox/.tox/bin/python -m virtualenv --no-download --python /home/sinoroc/workspace/dot-tox/.tox/.tox/bin/python .tox (exited with code 2)
________________________________________________ summary ________________________________________________
ERROR:   .tox: InvocationError for command /home/sinoroc/workspace/dot-tox/.tox/.tox/bin/python -m virtualenv --no-download --python /home/sinoroc/workspace/dot-tox/.tox/.tox/bin/python .tox (exited with code 2)

[sinoroc]

I have not tested those and they might well be covered already, but since we are here: are other names such as .tmp, dist, log, .package.lock, etc. already safe guarded?

[gaborbernat]

Those are within the tox environments, so they don't need safeguarding.

[gaborbernat]

Released now via https://tox.readthedocs.io/en/latest/changelog.html#v3-21-1-2021-01-13