pypa/pip — pull request #567 by qwcode (2012-06-06 03:06:07+00:00)
Title: --user fixes pt 3  Issue #493

this is part 3 of a breakup of pull request #511
full plan is here: https://gist.github.com/2822510

#493: pip shouldn't allow --user installs in virtualenvs (w/o --system-site-packages)