Re: proposed python change: removing python 3.7

["David H. Gutteridge" <david%gutteridge.ca@localhost>]

I don't object to removing Python 3.7 at this time, but I'd like to add
some comments.

Thomas Klausner wrote:
> We currently have to maintain the recursive limitations of
> PYTHON_VERSIONS_INCOMPATIBLE manually. This is a lot of effort and
> regularly breaks pbulk builds, and I don't think it's worth our time.

Given this is a significant concern, and a repeated issue which will
likely recur in future, I'm not following why this isn't automated with
a script akin to pkgtools/revbump, instead of ongoing manual efforts?
It's never worth anyone's time to do that sort of work manually. (I say
that as one of several people who were involved in fixing the pbulk
breakage this time around.)

nia wrote:
> I'm adding another vote to the "disagree" pile, for one reason
> alone, and that's that Python 3.7 was the default in pkgsrc
> for quite some time. I don't want to break people's scripts
> and so on before it's due.

Perhaps we need to distinguish between a basic dependency on 3.7 for
some specific custom coding reason vs. someone expecting it to continue
to work with all or most Python packages in pkgsrc? The latter isn't
realistic or reasonable. If someone were to say they'd like the base
Python 3.7 package to remain available, with no expectations it will
work with anything else from pkgsrc, that's more feasible.

I'm not sure how much value there'd be in keeping 3.7 itself around,
and blocking off all dependent packages to not accept it (at one point
in lang/python, not by using PYTHON_VERSIONS_INCOMPATIBLE)? This is
effectively what's done elsewhere, e.g., Fedora provides 3.6 onward
currently, for anyone who wants to continue testing with older
versions, but only the actual base package itself. They only support
one Python release at a time for any dependent packages, and say any
other use cases should install dependencies using pip instead.

If there is such demand, it seems comparatively simple to keep the base
3.7 package around (though, yes, there could be other hiccups, like
py-expat is part of the "base" distribution, but we break it out
separately). I'd be willing to help with that (speaking as a person
who's been applying back-ported Python 2.7 security updates, which if
anything is much more work). But, of course, not having 3.7 at all is
less work, which is nice.

Regards,

Dave