Re: [PATCH] RFC: switch: allow same-commit switch during merge if conflicts resolved

>
> On Sun, May 7, 2023 at 4:48 AM Elijah Newren <newren@gmail.com> wrote:
> >
> > On Wed, May 3, 2023 at 10:01 PM Tao Klerks <tao@klerks.biz> wrote:
> > >
> > > I believe this question was resolved later in the thread. The proposal
> > > is to allow the simplest case of merge only, for resolved
> > > (unconflicted) indexes only. If the change were to make sense I could
> > > update this message to be clearer that none of those other operations
> > > or situations are impacted by this change.
> >
> > As I mentioned to Junio, I understood fully that your implementation
> > limited the changes to this one case.  That did not resolve my
> > concerns, it merely obviated some other bigger ones that I didn't
> > raise.
> >
> > However, making it only available via a --force override (and then
> > perhaps also limiting it to just some operations), would resolve my
> > concerns.
> >
>
> Hmm, I think there is confusion here.
>
> My proposal was (and now, again, is) to add support for "--force" to
> "git switch", and to keep and improve that existing support for "git
> checkout" (where it is in my opinion broken during a rebase), but that
> proposal was mostly-unrelated to my main goal and proposal for
> supporting same-commit switches in the first place:
>
> A same-commit switch (*without* --force) serves the use-case of
> *completing a merge on another branch*. This is, as far as I can tell
> only *useful* for merges:
>  * during a rebase, switching in the middle (to the same commit,
> without --force) won't achieve anything useful; your rebase is still
> in progress, any previously rebased commits in the sequence are lost,
> and if you continue the rebase you'll end up with a very strange and
> likely-surprising partial rebase state)
>  * during a cherry-pick, it's just "not very useful" - it's not bad
> like rebase, because in-progress cherry-pick metadata is destroyed
>  * during am, and bisect I'm not sure, I haven't tested yet.
>
> The reason this in-progress is *valuable* for merges (in a way that it
> is not for those other states) is that the merge metadata not only
> says what you're in the middle of, but also contains additional useful
> information about what you've done so far, which you want to have be a
> part of what you commit in the end - the identity of the commit you
> were merging in.
>
> Supporting switch with --force, and having it implicitly destroy
> in-progress operation metadata, has value in that it makes it easier
> to break backwards compatibility of "git checkout" without impacting
> users' or tests' workflows; it helps make a change to make checkout
> safer; but it does not help with my other (/main?) objective of making
> it easy and intuitive to switch to another same-commit branch, to be
> able to commit your in-progress merge on another branch and avoid
> committing it where you started.
>
> Hence, if/when we add support for same-commit switching during merge
> (and potentially other operations, if that makes sense), it should
> *not* take "--force", which has a substantially different purpose and
> meaning.