Re: [PATCH v2 0/3] Ensure unique worktree ids across repositories

From: Eric Sunshine <sunshine@sunshineco.com>
Date: Dec 3, 2024, 00:56 UTC
Message-ID: <CAPig+cQHW9=A5ejU5aZ+Wy0uOQsLU_uqUibeYzZs2PXK37Vpbw@mail.gmail.com>
In-Reply-To: <xmqqed2pioff.fsf@gitster.g>

On Mon, Dec 2, 2024 at 7:46 PM Junio C Hamano <gitster@pobox.com> wrote:

Show 13 quoted lines

> shejialuo <shejialuo@gmail.com> writes:
> > But cross-ref operations between worktrees must explicitly specify the
> > worktree id, so I am wondering whether we should allow the user do
> > cross-ref operations in the first place:
> >
> >   1. main worktree symref points to linked worktree ref.
> >   2. A linked worktree ref points to another linked worktree ref.
>
> What is a cross-ref operation?  A worktree is either the primary
> working tree for a (non-bare) repository, or something added with
> "git add worktree" (i.e. whose .git is not the repository but a
> link file into the real repository).  Are you adding another mode
> where a worktree points at another worktree and not the repository?

Unfortunately, I haven't had time lately to follow all these worktree-related changes or discussions, but perhaps shejialuo is referring to the ability, from within one worktree, to mention a ref from another worktree (which is a feature Duy added some time after the initial worktree implementation). Specifically, from the git-worktree man page:

    Refs that are per-worktree can still be accessed from another
    worktree via two special paths, main-worktree and worktrees. The
    former gives access to per-worktree refs of the main worktree,
    while the latter to all linked worktrees.

    For example, main-worktree/HEAD or main-worktree/refs/bisect/good
    resolve to the same value as the main worktree’s HEAD and
    refs/bisect/good respectively. Similarly, worktrees/foo/HEAD or
    worktrees/bar/refs/bisect/bad are the same as
    $GIT_COMMON_DIR/worktrees/foo/HEAD and
    $GIT_COMMON_DIR/worktrees/bar/refs/bisect/bad.