About 25 formula in homebrew/core pass `--install-lib` to `python3` in
addition to `*setup_install_args` in order to ensure that all files are
installed into the formula's prefix rather than into a `site-packages`
directory in Python's keg.
Let's simplify these formulae by also adding the appropriate
`--install-lib` flag to `setup_install_args`.
A user may wish to use two use two brew-installed Python packages
together. For example, one might want to `import numpy` when using
`jupyterlab` or `ptpython`.
Currently, the only ways to do this I'm aware of is with some hacking of
`PYTHONPATH` or the creation of `.pth` files in a formula's prefix.
A better solution is to allow the virtualenvs that `brew` creates to
have access to system site-packages by default, so that `import numpy`
inside `ptpython` or `jupyterlab` just works.
Partially resolvesHomebrew/homebrew-core#76950.
This reverts commits 318175cfe2b23328f1b5f13812fd59cfd45fe1dc,
e7ab760392b9691a6c730b7e0d660b7874969e70 and
3b35af63f608438b1882756feca94a6ebdd0d6a3 (PR #11537).
If added, this makes the virtualenv read the main site-package from brewed Python,
and especially makes it read our sitecustomize.py file, which will
modify the sys.executable path.
See the full discussion at:
https://github.com/Homebrew/brew/pull/8873
I also took the opportunity to not include test deps, as these will
be not be installed, so the .pth file should not contains references
to site-packages from test deps.
Previous packages on Linux did already contain the wrong lines in the pth file,
for example:
cat /home/linuxbrew/.linuxbrew/Cellar/aws-google-auth/0.0.36_1/libexec/lib/python3.8/site-packages/homebrew_deps.pth
import site; site.addsitedir('/home/linuxbrew/.linuxbrew/opt/python@3.8/lib/python3.8/site-packages')
import site; site.addsitedir('/home/linuxbrew/.linuxbrew/opt/libxml2/lib/python3.8/site-packages')
This might have caused subtle bugs for some packages but not for others.
