Re: [PATCH 00/14] Change python-build-system (fixes bug 20765)

[Hartmut Goebel <h.goebel@crazy-compilers.com>]

Am 30.09.2016 um 16:39 schrieb Marius Bakke:

> Also some packages are missing a dependency on "python-py"[1].

FYI: I found an example: python-pytest-cov fails in the "check" phase.
This is an undocumented requirement for the tests, resp. this is an
install-requirement for pytest, but pytest has "python-py" defined as a
normal input.

I investigated this and found that the existing build-system was kind of
broken :-( Prior to my changes, a .pth file was created in
in many cases - while now it is never creates.

(For those not common to Python: .pth-files are an old way to specify
additional directories to be added to sys.path (PYTHONPATH). .pth-file
were rarely used until setuptools and easy-install came up. And now
since pip is the recommended install method, they are bound to vanish
again.)

This .pth file did not only point to the .egg-directory (or file, in
case of a zipped .egg), but also to the .eggs of the requirement of the
current package. In the case of pytest, the .pth file looked something
like thus:

   ./pytest-1.2.3.egg
   /gnu/store/…-python-py-3.2.1/lib/python3.4/site-packages/py-3.2.1.egg

Thus the .pth-file did "propagate" the inputs.

Due to my change the .pth-file is gone now, and thus all required inputs
need to be declared as propageded-inputs as uix.

I'm working on this, but it requires to have a look at many of the
packages' source to do it right and will take some days to finish.

-- 
Regards
Hartmut Goebel

| Hartmut Goebel          | h.goebel@crazy-compilers.com               |
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