bug#43893: [PATCH] maint: update-guix-package: Ensure sources are clean.

[Maxim Cournoyer <maxim.cournoyer@gmail.com>]

Hi Ludovic,

Ludovic Courtès <ludo@gnu.org> writes:

> Hi,
>
> Maxim Cournoyer <maxim.cournoyer@gmail.com> skribis:
>
>> Ludovic Courtès <ludo@gnu.org> writes:
>>
>> [...]
>>
>>>> * build-aux/update-guix-package.scm (git-add-worktree): New procedure.
>>>> (main): Use it to checkout a clean copy of the used commit, and compute the
>>>> hash from it.  Print a user warning after completion.
>>>
>>> I’m not quite enthusiastic about the tool creating a worktree behind my
>>> back.
>>
>> May I ask why?  It's not something you'd (need to) be aware of (it
>> doesn't leave traces in my v2 as 'git worktree prune' clears up the
>> temporary worktree entries), and it's quite cheap to create.
>
> To me, this is all my workspace, and I generally assume I’m the only one
> touching it; it’s more about the mental model, I guess.

I see. I understand your position, but also feel it's not a big deal
here, given you wouldn't be able to notice a new worktree unless you
watch the output of 'git worktree list' in a loop while updating the
guix package ;-).

I think the change brings good guarantees to guard against breaking
'guix pull' with a 'make update-guix-package' as it is, and also
documents the thing.  If it's OK with you I'd like to merge it in the
coming days.

Thanks,

Maxim