Improve basic documentation in description

[merwok]

Hello! I found this plugin when looking for doc about Python / tox usage in CircleCI. The current doc doesn’t explain clearly what problem it solves, and my tox config that doesn’t use it seems to work.

[stavxyz]

Hi @merwok, check these out:

https://github.com/yyuu/pyenv/issues/92#issuecomment-145351621

https://github.com/samstav/circleci-python-sandbox/issues/1

[stavxyz]

The documentation here definitely needs updating though, thanks for pointing this out.

[merwok]

The second link is helpful, thanks! I am using the pyenv local trick in my config, but I haven’t confirmed yet that the right versions are picked up.

[stavxyz]

Yeah, you might want to assert that the exact python version you expect to be running is in fact running your tests. In fact, it was only when I added these assertions and they started failing when when I got worried and was motivated to write this plugin. The very tests for this plugin itself do exactly this (assert the exact version) as part of the test suite for tox-pyenv. See the environment variables set as TOX_*:

https://github.com/samstav/tox-pyenv/blob/master/circle.yml

Then passed through via tox config:

https://github.com/samstav/tox-pyenv/blob/master/tox.ini#L8

and the python version is asserted to be exactly as it is set during the test:

https://github.com/samstav/tox-pyenv/blob/master/test_tox_pyenv.py#L30-L52