[Distutils] can someone explain why I have started to get these pip failures

[Jeremy Stanley]

On 2016-07-14 17:23:24 +0100 (+0100), Robin Becker wrote:
> not really sure why this is an issue. All of my problems are in virtual
> environments and I never use the --system-site-packages flag.
> 
> I have never used pip to install anything system wide (so far as I know).

Ahh, whoops, after rereading back through some of your earlier
messages in the thread I see this is indeed all in the scope of a
virtualenv.

> Step 0 in after setting up an environment is pip install -U pip setuptools
> 
> Of course you are right in that the python is a distro provided one; and
> also the pip and virtualenv etc etc.
[...]

I've noticed in the past that for some reason the system
pkg_resources can end up getting used by setuptools (on
Debian/Ubuntu it's unvendored and split into a separate
python-pkg-resources deb). I haven't had an opportunity to track it
down. You might try myenv/bin/python -c 'import sys;print sys.path'
and then check the results in order to see which the first one is to
provide pkg_resources.

Hunting around a bit, this looks similar to
https://github.com/pypa/setuptools/issues/497 so see if any of the
suggestions mentioned there help at all.

> When I run python -mvirtualenv I end up with an environment that has pip and
> setuptools already. Are you saying I should do
> 
> /usr/bin/python -mvirtualenv --no-pip --no-setuptools myenv
> myenv/bin/python get_pip.py
[...]

No, but you might try bootstrapping a newer version of virtualenv
into its own virtualenv, like:

    virtualenv foo
    foo/bin/pip install -U pip setuptools virtualenv
    foo/bin/virtualenv myenv

Doing that on some systems where I'm forced to start from
distro-provided pip/setuptools/virtualenv has worked out
consistently well.
-- 
Jeremy Stanley