dear python@freebsd.org: please include a .egg-info for py-twisted

[Zooko O'Whielacronx]

Dear python at freebsd.org folks:

I contribute to some open source software written in Python
(http://tahoe-lafs.org ) and we rely on the standard Python
metadata—which is named ".egg-info" for legacy reasons even though it
doesn't have anything to do with Python Eggs—to detect whether other
Python packages are installed. This works for all packages on FreeBSD
since the standard Python distutils build the appropriate .egg-info
files automatically and the FreeBSD packagers correctly include those
files, but it doesn't work for Twisted.

That's because a few years ago the Twisted folks split Twisted into
several separate packages, like "Twisted-Core", "Twisted-Web",
"Twisted-Words" and so on. After a couple of released the Twisted
folks decided this was more trouble than it was worth and went back to
distributing a monolithic "Twisted" package, but for some reason all
of the operating system distributions have continued to maintain the
split-out packages.

Anyway, the problem is that the py-twisted metapackage that depends on
all the other split-out packages doesn't produce a
"Twisted-$VERSION.egg-info" file, so therefore when our code asks "Is
Twisted installed?" the answer appears to be no, since there is no
"Twisted-$VERSION.egg-info" file present.

Here is the issue ticket from when Debian had a similar problem which
shows you how they solved it:

http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=477384

Here is the issue ticket from Fedora:

https://bugzilla.redhat.com/show_bug.cgi?id=523210

To fix this issue, make it so that when the py-twisted package is
installed, then there exists a file named
"Twisted-$TWISTEDVERSION-py$PYTHONVERSION.egg-info" on the sys.path.

Thanks!

Regards,

Zooko Wilcox-O'Hearn