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

> Hi Phillip,
> 
> On Mon, 25 Nov 2019, Phillip Wood wrote:
> 
>> On 25/11/2019 03:00, Junio C Hamano wrote:
>>> Phillip Wood <phillip.wood123@gmail.com> writes:
>>>
>>>> We do actually check that there is a valid HEAD before we try to fixup
>>>> a commit. Though perhaps we should still change this patch as HEAD may
>>>> be changed by another process between that check and re-reading it
>>>> here. If you try to fixup a commit without a valid HEAD you get
>>>>
>>>> error: need a HEAD to fixup
>>>> hint: Could not execute the todo command
>>>> hint:
>>>> hint:     fixup faef1a5a7637ff91b3611aabd1b96541da5f5536 P
>>>> hint:
>>>> hint: It has been rescheduled; To edit the command before continuing,
>>>> hint: please
>>>> hint: edit the todo list first:
>>>> hint:
>>>> hint:     git rebase --edit-todo
>>>> hint:     git rebase --continue
>>>> error: could not copy '.git/rebase-merge/message-squash' to
>>>> '.git/rebase-merge/message'
>>>>
>>>> The last error message is unfortunate but we do exit in an orderly
>>>> manner rather than segfaulting.
>>>
>>> Thanks for thinking about the issue further.
>>>
>>>> diff --git a/t/t3404-rebase-interactive.sh b/t/t3404-rebase-interactive.sh
>>>> index d2f1d5bd23..4f55f0cd1c 100755
>>>> --- a/t/t3404-rebase-interactive.sh
>>>> +++ b/t/t3404-rebase-interactive.sh
>>>> @@ -67,6 +67,21 @@ test_expect_success 'setup' '
>>>>    SHELL=
>>>>    export SHELL
>>>>
>>>> +test_expect_success 'fixup on orphan branch errors out' '
>>>> +
>>>> +       test_when_finished "git switch master" &&
>>>> +       write_script switch-branch.sh <<-\EOF &&
>>>> +       git symbolic-ref HEAD refs/heads/does-not-exist &&
>>>> +       git rm -rf .
>>>
>>> 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`?