Re: [PATCH v3 4/6] worktree: new config file hierarchy

[Duy Nguyen <pclouds@gmail.com>]

On Fri, Jan 29, 2016 at 1:45 AM, Junio C Hamano <gitster@pobox.com> wrote:
> Would it make it simpler to invent a specific value for 'xxx' that
> denotes the main worktree (hence $C/worktrees/xxx/config will always
> be read by worktrees including the primary one), not to add
> $C/common/ anything, and use $C/config as the common one instead?
>
> Then the repository format version can live in $C/config that would
> be noticed by existing versions of Git.

I can read this in two ways. In the first way, we still have $C as a
.git _directory_ that contains no worktree stuff because those files
are in $C/worktrees/main. When we detect .git directory we need to
decide if it this is worktree v1 and redirect $GIT_DIR to
$C/worktrees/main, otherwise keep $GIT_DIR as $C. This messes up setup
code a lot (I tried).

The other way, probably a bit deviated from your intention, is, we
only support two modes: either all worktrees are in $C/worktrees
(multiple worktree mode), or there's only one worktree at .git (single
worktree mode). In other words, there's no mixing main and linked
worktrees. The user will be forced to convert the main worktree to
linked worktree when they want to add a another tree. The backward
compatibility issue with worktree v0 is gone.

The transition between two modes can be done via "git worktree move".
This command can move any worktree, including the main one. Main
worktree is converted when it's moved (.git directory remains where it
is). "worktree move" can also move repository directory, which also
automatically convert main worktree to $C/worktrees/something. If the
user deletes all worktrees except one, they can move the repo back to
worktree's root, which converts it back to the single worktree mode.

Hmm?
-- 
Duy