Isolation issues in tests/functional/test_help.py

[cytolentino]

Environment

• pip version: 18.1
• OS: Mac OS High Sierra 10.13.6

Description

When running tox -e py36, test_help_commands_equally_functional in tests/functional/test_help.py fails because of the following

E             -                 https://pypi.org/simple). This should point to a
E             +                 https://pypi.python.org/simple). This should

E             -   --timeout <sec>             Set the socket timeout (default 15 seconds).
E             ?                                                               ^^
E             +   --timeout <sec>             Set the socket timeout (default 23.0 seconds).

which is caused by my PIP_INDEX_URL being set as follows:

$ echo $PIP_INDEX_URL
https://pypi.python.org/simple

and my pip.conf being set as follows:

$ cat ~/.pip/pip.conf
[global]
timeout = 23

How to Reproduce

1. Set timeout in pip.conf to some value != 15
2. Set PIP_INDEX_URL environment variable to something other than https://pypi.org/simple
3. Run tox -e py36 tests/functional/test_help.py -vv

[cytolentino]

Because of user_dir in here being declared before anything else, expanduser returns the user's $HOME despite os.environ['HOME'] being set to a temporary directory here.

Thus, the isolate test fixture (see here) does not manage to prevent the test suite from reading the user's config files.

[chrahunt]

I was able to reproduce this with the provided instructions. I think in general it's probably a good idea to recompute the values in locations that may be context/environment-dependent. That will also help #4497 since it can enable more in-memory tests.

[xavfernandez]

#6736 fixed this.