Re: pull.rebase config option broken in 2.33.1

[Jeff King <peff@peff.net>]

On Fri, Nov 26, 2021 at 04:44:52PM -0500, Jeff King wrote:

> +cc Alex and Elijah from the original 3d5fc24dae (pull: abort if
> --ff-only is given and fast-forwarding is impossible, 2021-07-21) in
> case they have further thoughts, but I _think_ this is working as
> designed.

Whoops, forgot the cc. Original message in full below.

-Peff

> On Fri, Nov 26, 2021 at 09:05:46PM +0300, Dmitry Marakasov wrote:
> 
> > * Jeff King (peff@peff.net) wrote:
> > 
> > > > After update from 2.33.0 to 2.33.1 the pull.rebase = true option
> > > > no longer works: `git pull` no longer tries to rebase (however manual
> > > > `git pull --rebase` works fine):
> > > > 
> > > > % git config pull.rebase
> > > > true
> > > > % git pull
> > > > fatal: Not possible to fast-forward, aborting.
> > > > % git pull --rebase
> > > > Successfully rebased and updated refs/heads/local-fixes.
> > > > % git pull
> > > > fatal: Not possible to fast-forward, aborting.
> > > > % grep -C1 rebase .git/config
> > > > [pull]
> > > > 	rebase = true
> > > > [rebase]
> > > > 	autostash = true
> > > > 
> > > > After downgrade to 2.33.0:
> > > > 
> > > > % git pull
> > > > Current branch local-fixes is up to date.
> > > 
> > > This looks like the same bug discussed in:
> > > 
> > >   https://lore.kernel.org/git/CH2PR06MB650424B4205102AC6A48F489B1BD9@CH2PR06MB6504.namprd06.prod.outlook.com/
> > > 
> > > There's a fix in that thread. It's currently in "next", but didn't quite
> > > make the cutoff for the upcoming v2.34.0.
> > 
> > For the record, the problem is still present in 2.34.1
> 
> In the bug I linked (and what got fixed in 2.34.1), the issue is that
> when the local branch is ahead of the remote, we don't say "up to date",
> but complain about fast-forwards.
> 
> It's hard to tell from the output above, but it looks like you have a
> case where there are new commits both locally and on the remote? In
> which case a rebase would work just fine.
> 
> But why are we complaining about "not possible to fast-forward"? Testing
> locally with something like:
> 
> -- >8 --
> git init repo
> cd repo
> 
> commit() {
> 	echo $1 >$1
> 	git add $1
> 	git commit -m $1
> }
> 
> git checkout -b local
> commit base
> commit local
> 
> git checkout -b remote HEAD^
> commit remote
> 
> git checkout local
> git config pull.rebase true
> git pull . remote
> -- >8 --
> 
> shows that we do rebase. If I set:
> 
>   git config pull.ff only
> 
> then we start complaining. And that behavior did change in 2.33.1, but
> I'm not sure it's wrong. We have two conflicting config options, and the
> precedence for which one we pick switched.
> 
> Do you have that option set in your config? Try:
> 
>   git config --show-origin --show-scope --get-regexp 'pull\..*'
> 
> 
> -Peff