include only selected packages from the global site-packages

[pytoxbot]

• Bitbucket: https://bitbucket.org/hpk42/tox/issue/79
• Originally reported by: @derdon
• Originally created at: 2012-12-21T17:33:59.685

With the option sitepackages set to True, it is possible to access all the packages from the global site-packages directory. However, it is not possible to include only certain packages from the global site-packages directory. It would be a useful feature to have a config option like globalpackages to define a list of packages which should be linked to the current active virtualenv.

[pytoxbot]

Original comment by @hpk42

You can put things like $(which coverage python-coverage|head -n 1) into
a shell script and call it from the tox commands, though.

Otherwise i don't think we can do anything about the sitepackages logic --
this is really core functionality of virtualenv which tox is merely using
and not meddling with itself.

[pytoxbot]

Original comment by rhertzog

I would definitely love such an option. I have to use sitepackages=True because some Python modules such as python-apt come from the debian system and are not available via pip. But then there are other modules such as coverage that I don't want to take from the system because the debian package (rightfully) renames the script to python-coverage while the pip installed module provives a "coverage" script and I can't support both names with tox...

I tried using $(which coverage python-coverage|head -n 1) but shell substitution is not allowed. :)