Re: [PATCH v2 1/1] sequencer: fix empty commit check when amending

[Johannes Schindelin <Johannes.Schindelin@gmx.de>]

Hi Eric,


On Mon, 25 Nov 2019, Eric Sunshine wrote:

> On Mon, Nov 25, 2019 at 10:54 AM Johannes Schindelin
> <Johannes.Schindelin@gmx.de> wrote:
> > On Mon, 25 Nov 2019, Phillip Wood wrote:
> > > On 25/11/2019 03:00, Junio C Hamano wrote:
> > > > That "git rm -rf ." scares me, though.
> > >
> > > I know I'm not too keen on it my self but we need to empty the worktree and
> > > index if we're going to switch to an unborn branch
> >
> > How about `git worktree --orphan does-not-exist unborn`?
>
> git-worktree doesn't presently recognize --orphan, though it would be
> nice if it did. In fact, I clearly was thinking of --orphan (along
> with -b, -B, and --detach), when I wrote the implementation, as can be
> seen from the commentary in one of the original patches[1]. That
> --orphan never got added was either due to an oversight or it was one
> of those "we'll add it when someone actually needs it" deals.
>
> [1]: https://lore.kernel.org/git/1436573146-3893-11-git-send-email-sunshine@sunshineco.com/

You're absolutely correct, of course. I actually had looked at the output
of `git checkout -h` instead of `git worktree -h`... And `checkout` does
have that `--orphan` option.

But from the documentation at
https://git-scm.com/docs/git-checkout#Documentation/git-checkout.txt---orphanltnewbranchgt
I see that the command I had in mind does not work as I expected it to:
`git checkout --orphan new-branch $EMPTY_TREE` will fail with
fatal: Cannot switch branch to a non-commit '4b825dc642cb6eb9a060e54bf8d69288fbee4904'
(and the documentation of the `--orphan` option also suggests to use `git
rm -rf` for the use case under discussion, so there...)

Sorry for the noise,
Dscho