[TIP] RFC: tox-2.0 to restrict/isolate env variables in test runs

[Roy Wright]

On Jun 9, 2015, at 1:09 PM, holger krekel <holger at merlinux.eu> wrote:

> Roy, David,
> 
>> On Tue, Jun 09, 2015 at 11:14 -0500, Roy Wright wrote:
>>> On Jun 9, 2015, at 10:00 AM, David Cournapeau <cournape at gmail.com> wrote:
>>> 
>>> I am late to the party, and I guess it is too late, but I am not convinced this is a good idea, at least not as a default (should be opt-in, not opt-out).
>>> 
>>> This breaks a lot of basic features, in a way that is fairly complicated to debug. E.g. with tox 2.0, os.path.expanduser("~") is now broken on windows because e.g. USERNAME is not propagated. Realistically, way too many programs depend on various environment variables.
>> 
>> If you are behind a firewall, you may need to pass in your proxy variables so pip can connect to pypi.python.org, even if you are using an internal index. I.e., tox fails to create a virtualenv. Not good. 
>> 
>> I'd prefer to be able to set options that affect all usages of a utility globally instead of needing to add to every project I want to test. 
>> 
>> I can understand the need to totally control the test environment. It's just that there are system needs that must be met before test needs.
> 
> Would it help you if we introduce a TOX_PASSENV environment variable
> (and maybe a command line option) that is honored in addition to 
> the tox.ini values?  You could set that on a per-system basis.

I could live with that. :-)

A list of platform examples would be nice. 

My preference would be a ~/.toxrc just because you can include comments and examples. 

With an environment variable if you explain it in the tox --help is ok.

Either way would need to be easily found when things blow up. 

Thank you!