sphinx-build hard codes the python interpreter #92

I don't think this is something that needs to be fixed, but documenting here.

$ ssh cobalt 'command cat /cvmfs/icecube.opensciencegrid.org/py3-v4.4.1/RHEL_7_x86_64_v2/bin/sphinx-build'
#!/cvmfs/icecube.opensciencegrid.org/py3-v4.4.1/RHEL_7_x86_64_v2/bin/python
# -*- coding: utf-8 -*-
import re
import sys
from sphinx.cmd.build import main
if __name__ == '__main__':
    sys.argv[0] = re.sub(r'(-script\.pyw|\.exe)?$', '', sys.argv[0])
    sys.exit(main())

This seems to be a Sphinx thing vs a packaging thing, it's the same with DEB or RPM packages. In general this isn't a big deal, but confusion arises when you're using the "system" (ie. CVMFS) sphinx-build with an extension installed in your Python virtual env. Because it's calling the "system" Python, the user's virtual env isn't part of PYTHONPATH, so it never sees those extensions.

The easy fix is to just add Sphinx to your virtual env with pip3 install --upgrade sphinx.