Subject: Re: init --separate-git-dir does not set core.worktree

From: Kyle Meyer <[email-masked]>
Date: Thu, 02 Feb 2017 07:37:40 -0500

Duy Nguyen <[email-masked]> writes:

> On Thu, Feb 2, 2017 at 10:55 AM, Kyle Meyer <[email-masked]> wrote:
>>
>> As of 6311cfaf9 (init: do not set unnecessary core.worktree,
>> 2016-09-25), "git init --separate-git-dir" no longer sets core.worktree
>> (test below).  Based on the commit message and the corresponding thread
>> [1], I don't think this change in behavior was intentional, but I wasn't
>> able to understand things well enough to attempt a patch.
>
> I'm missing some context. Why does --separate-git-dir have to set
> core.worktree? What fails for you exactly?

Sorry for not providing enough information.  I haven't run into a
failure.

In Magit, we need to determine the top-level of the working tree from
COMMIT_EDITMSG.  Right now that logic [*1*] looks something like this:

 * COMMIT_EDITMSG in .git/modules/<module>/: set working tree to the
   output of "git rev-parse --show-toplevel"

 * COMMIT_EDITMSG in .git/worktrees/<wtree>/: set working tree to the
   path in .git/worktrees/<wtree>/gitdir, minus the trailing "/.git"

 * COMMIT_EDITMSG in .git: set working tree to the parent directory

This fails for a repo set up with --separate-git-dir [*2*], where the
last step will go out into an unrelated repo.  If core.worktree was set
and "git rev-parse --show-toplevel" returned the working tree like it
did for submodules, things would work.

Of course, the issue above isn't a reason that --separate-git-dir should
set core.worktree, but the submodule behavior is why we were wondering
if it should.  And so I was going to ask here whether core.worktree
should be set, but then I confused myself into thinking 6311cfaf9
unintentionally changed this behavior.

[*1*] This is done by magit-toplevel:
      https://github.com/magit/magit/blob/e34f4e8eb00f292e8c475489fa7caa286857a421/lisp/magit-git.el#L400

[*2*] https://github.com/magit/magit/issues/2955
      https://github.com/magit/magit/issues/2981