[Python-modules-team] Bug#907352: please make texinfo generation reproducible

[Nicholas D Steeves]

Package: python3-sphinx
Version: 1.7.7-1
Severity: important

Dear Sphinx maintainers,

Thank you for maintaining python3-sphinx.  I've set the severity of
this bug to important, because I believe this bug affects all packages
that generate info pages using Sphinx.

Here is an example of the unreproducibility on DebCI:
  https://tests.reproducible-builds.org/debian/rb-pkg/unstable/amd64/elpy.html

I'm using this in debian/rules:
    PYTHONPATH=. sphinx-build -N -btexinfo docs/ build/info                 
    makeinfo --no-split build/info/Elpy.texi -o build/info/elpy.info

Stuart Prescott helped me identify the cause on #debian-python and mentioned that it also affects "python-bumps", and I've CCed him.

In #debian-mentors Jakub Wilk mentioned that it's possible to
workaround with something like: PYTHONHASHSEED=0

It follows that a temporary workaround using a date stamp from the
most recent changelog entry as a hash seed might not be terrible, but
it would be much better if the root cause was addressed.

Cheers,
Nicholas