Re: [Outreachy][Proposal]: Refactor in order to reduce Git’s global state

From: Christian Couder <christian.couder@gmail.com>
Date: Oct 30, 2025, 12:55 UTC
Message-ID: <CAP8UFD1v7yec7JwBGekJPvcq7kNJPuPTgWOVn+gBaw1+Sh2mdA@mail.gmail.com>
In-Reply-To: <CAD=f0L8=eBJjj77xBw7m7WcQf80sYbF-X1wbFc9ToC9F0AWVAQ@mail.gmail.com>

On Thu, Oct 30, 2025 at 11:59 AM Bello Olamide <belkid98@gmail.com> wrote:

> On Wed, 29 Oct 2025 at 16:51, Christian Couder
> <christian.couder@gmail.com> wrote:
> > On Wed, Oct 29, 2025 at 2:18 AM Bello Olamide <belkid98@gmail.com> wrote:

Show 19 quoted lines

> > > I also studied [3], [4] by Ayush Chandeker,] and [5] by John Cai to broaden my
> > > understanding of the project.
> >
> > Are there some cases where strategies other than writing new accessors
> > functions were used?
>
> Yes there were cases where the functions were adapted to use
> exactly what it needs down the call chain rather than writing new
> accessor functions.
> An example is
> https://public-inbox.org/git/20250306-b4-pks-objects-without-the-repository-v2-1-f3465327be69@pks.im/#Z31csum-file.h
> where the global variable `the_hash_algo` is replaced with an explicit parameter
> `const struct git_hash_algo *algo` in low-level functions such as
> `static struct hashfile *hashfd_internal()` and the call sites adapted
> to use r->hash_algo
> or the_repository->hash_algo in places where the subsystem has not gotten rid of
> `the-repository`.
>
> This is also a strategy that can be used to replace global variables.

Your answers are appreciated, but, just to be clear, I think it would be nice if the answers to my questions like this one were part of a v2 of your proposal. If I don't see a v2, I am less tempted to discuss this further (which could hopefully help move the analysis forward and make your proposal better).

Thanks.