bug#45836: cups-service-type duplicates lp group

["Ludovic Courtès" <ludo@gnu.org>]

Hi Leo,

Leo Prikler <leo.prikler@student.tugraz.at> skribis:

>> I’d be pragmatic here:
>> 
>>   1. Ignore duplicates that are identical (don’t report them).
> Is that still not a problem, because either definition could change?

Sure, but that’s a separate issue, which is what #2 addresses.

>>   2. Remove “lp” from %base-groups since it has no use without CUPS
>>      (right?).
> That's probably true, but I fear, that some have already added "lp" to
> their config.scm.  Would that cause issues?

Presumably everyone uses ‘%base-groups’ and thus everyone already has a
definition of “lp”, coming from Guix itself.

On second thought, my proposal was not so good because as the comment in
(gnu system shadow) suggests, there are default udev rules that refer to
the “lp” group.  So it has to exist (to be on the safe side at least).

So perhaps we can leave things unchanged and simply add a comment in
(gnu services cups) that the “lp” group definition is redundant but kept
here for clarity.

WDYT?

If the two “lp” eventually come to differ, we’ll notice via system
tests… and bug reports.

> We could also add CUPS to
> %base-services or %desktop-services in some way, but that would
> probably cause issues with configurations, that already have it.

Adding CUPS by default is not a reasonable option, no.  :-)

Thanks,
Ludo’.