run-tests: stop ignoring venv-installed packages
This will allow test dependencies to be installed within a venv, instead of
tampering with sys/user sites. One thing to note here is that the `VIRTUAL_ENV`
path takes precedence over system-site, unlike when run directly with an
activated `venv`. For example, `sys.path` as viewed from a feature test in
`hghave.py`, when running `hghave vcr` directly with an activated `venv`:
sys.path: [
'/home/jenkins/hg-committed/tests',
'/usr/lib/python38.zip',
'/usr/lib/python3.8',
'/usr/lib/python3.8/lib-dynload',
'/home/jenkins/test_venv/lib/python3.8/site-packages'
]
vs `sys.path` from the same feature test, when run by `run-tests.py` with this
change:
sys.path: [
'/home/jenkins/hg-committed/tests',
'/home/jenkins/hg-committed',
'/home/jenkins/hg-committed/tests',
'/home/jenkins/test_venv/lib/python3.8/site-packages',
'/usr/lib/python38.zip',
'/usr/lib/python3.8',
'/usr/lib/python3.8/lib-dynload',
'/home/jenkins/.local/lib/python3.8/site-packages',
'/usr/local/lib/python3.8/dist-packages',
'/usr/lib/python3/dist-packages'
]
$ hg init
$ echo 123 > a
$ hg add a
$ hg commit -m "first" a
$ mkdir sub
$ echo 321 > sub/b
$ hg add sub/b
$ hg commit -m "second" sub/b
$ cat sub/b
321
$ hg co 0
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ cat sub/b 2>/dev/null || echo "sub/b not present"
sub/b not present
$ test -d sub || echo "sub not present"
sub not present