Re: git guix checkout automation for contributors

[Josselin Poiret <dev@jpoiret.xyz>]

Hello everyone,

zimoun <zimon.toutoune@gmail.com> writes:

> Hi,
>
> On dim., 25 sept. 2022 at 21:40, kiasoc5 <kiasoc5@disroot.org> wrote:
>> Isn't there a checkout cache in ~/.cache/guix? Can guix edit be pointed
>> to the git repo in the cache as opposed to the system's?
>
> This checkout* is used by “guix time-machine” and it does not always
> point to what “guix describe” returns.  Modulo this minor warning
> (easily fixable by moving HEAD to the correct commit), it appears to me
> a good idea to rely on it for easing some contributions.

It would be a good idea to reuse the cache, however I don't think that
edits should be made directly there.  Maybe we could either suggest or
provide a command that would copy the git repository there to another
place.

> When running “guix time-machine” (inferiors), all the machinery
> “./bootstrap && ./configure --localstatevar=/var && make” is
> transparently done.  We discussed that at the 10 Years event with
> Josselin.

Yes!  Although FTR none of bootstrap, configure or make are actually run
when using time-machine, it's a totally different way of building :).
The upshot is that we could even provide a flag like `guix time-machine
--issue=NNNNN` that would provide the corresponding guix branch at
https://git.guix-patches.cbaines.net/guix-patches/, and benefit from the
built substitutes if there are.  It would need some more formal URL and
discussion around this feature, but everything's in place for it to
happen.

> Therefore, we could imagine something similar for helping people to
> contribute:
>
>  1. use (test?) unmerged patches
>  2. update and/or create new patches

I think the second part would need a bit of work though, refer to Chris'
mail [1] for what would need to be done (namely, making `git send-email`
easier and refactoring the contribution guidelines).

[1] 87a66wfzeh.fsf@cbaines.net
    https://yhetil.org/guix-devel/87a66wfzeh.fsf@cbaines.net

Best,
-- 
Josselin Poiret