Re: [PATCH 0/4] deprecating core.preferSymlinkRefs

[Derrick Stolee <stolee@gmail.com>]

On 9/18/24 7:28 PM, Junio C Hamano wrote:
> Removal of support for core.preferSymlinkRefs at Git 3.0 boundary,
> so that we only write textual symrefs for things like HEAD and
> refs/remotes/origin/HEAD, and still understand symbolic links used
> as symrefs in existing repositories, is a serious proposal this
> patch series makes.

I missed a lot of this discussion about 3.0, but I'm fascinated by
the prospect.

> What I want people to think about is how to ensure quality of the
> Git 3.0 phase.  We can iterate and polish the proposal phase with as
> much time as we want to spend, just like any new feature.  But Git
> 3.0 phase is with a solid deadline, and before that time, we cannot
> remove the feature for real.  Would we cook such steps in 'next'
> forever until the actual Git 3.0?  To those users who are running
> 'next' based Git, it would mean that some of the changes the
> breaking changes document listed would come a lot earlier to them.
> On the other hand, unless we somehow have a way to expose willing
> volunteers an early access to these "big changes", there is no way
> for them to be as stable and tested.  We should not plan to scramble
> and be able to perfect these changes between Git v3.0-rc0 and Git
> v3.0 final.
> 
> Or perhaps use the "experimental.*" configuration stored in the
> user's ~/.gitconfig to let users opt into Git 3.0 features (one of
> which may be that textual symrefs are always used regardless of the
> core.preferSymlinkRefs setting)?  That way, we can merge these big
> changes early without worrying about accidentally affecting the
> end-user population.
I do like the idea of having someone set 'feature.git3=true' in
their global config and having that mean that they are ready to
accept the Git 3.0 breaking changes as they are available in
a Git 2.x release. As much early testing as we can get would be
beneficial.

This would be a way to get your patches 2 & 3 into 'master' and
released, but I'm not sure exactly how to keep patch 4 queued
for a potential future release. The best I could think of is to
have a long-running 'master-v3' branch that takes these cleanup
patches and then merges ongoing 'master' changes into them. It
would be a gross history to manage, but it could potentially
work. It does lead to concerns as to how to communicate that a
change to 'master' has broken the 'master-v3' CI or how an
incoming change could create conflicts with 'master-v3'.

Sorry I don't have full solutions for you. Only more problems.

Thanks,
-Stolee