Pass through LANG environment variable by default

[pytoxbot]

• Bitbucket: https://bitbucket.org/hpk42/tox/issue/247
• Originally reported by: @asottile
• Originally created at: 2015-05-17T02:57:45.205

This renders io.open() and py3 open() pretty useless without it on linux at least (as they will use ASCII instead of the platform's default encoding)

[pytoxbot]

Original comment by @hpk42

tox-2.0.2 adds LANG to the default set (just released).

[pytoxbot]

Original comment by @msabramo

Along a similar line to @aconrad (we work at the same company), I also took a stab though I did it by adding a --passenv command-line option so that folks can decide on their own what environment variables should be passed, and do so without changing tox.ini.

https://bitbucket.org/hpk42/tox/pull-request/162/add-passenv-cli-option/diff

[pytoxbot]

Original comment by @aconrad

I submitted a pull request here to get the conversation started. https://bitbucket.org/hpk42/tox/pull-request/161/pass-lang-variable-to-the-test-environment/diff

[pytoxbot]

Original comment by @aconrad

Yes please! All my tox projects started failing with Python 3 because the LANG environment variable is no longer passed.

Also this makes projects using Click under Python 3 unusable.

https://github.com/mitsuhiko/click/blob/0d9731e97c9af9e5b0f5fd8421aeb0184ad42b70/click/core.py#L577-L589

[pytoxbot]

Original comment by @homeworkprod

I stumbled across this as well.

A package (Arrow, in my case; see arrow-py/arrow#224 for my bug report against the project) won't install on my CI because tox doesn't pass LANG along to pip.

Explicitly specifying environment variables in the tox configuration file seems to be a workaround, but I'd prefer to be able to change the locale tox (and its subprocesses) uses right from the command line.

[pytoxbot]

Original comment by @asottile

Hitting this here: ekalinin/nodeenv#123
and here: https://travis-ci.org/asottile/css-explore/builds/62762790