Re: [PATCH v3 11/20] path: construct correct path to a worktree's index

> When working with worktrees the git directory is split into two part,
> the per-worktree gitdir and a commondir which contains things which are
> shared among all worktrees (like the object store).  With this notion of
> having a split git directory, 557bd833b (git_path(): be aware of file
> relocation in $GIT_DIR) and c7b3a3d2f ($GIT_COMMON_DIR: a new
> environment variable) changed the way that 'git_path()' functioned so
> that paths would be adjusted if they referred to files or directories
> that are stored in the commondir or have been changed via an environment
> variable.
>
> One interesting problem with this is the index file as it is not shared
> across worktrees yet when asking for a path to a specific worktree's
> index it will be replaced with a path to the current worktree's index.
> In order to prevent this, teach 'adjuct_git_path' to replace the

> path to the index with the path recorded in a repository (which would be
> the current, active worktree) only when not asked to construct a path
> for a specific worktree.
>
> Signed-off-by: Brandon Williams <bmwill@google.com>
> ---
>  path.c | 11 +++++++++--
>  1 file changed, 9 insertions(+), 2 deletions(-)
>
> diff --git a/path.c b/path.c
> index 76a872297..c6832a30e 100644
> --- a/path.c
> +++ b/path.c
> @@ -372,13 +372,20 @@ void report_linked_checkout_garbage(void)
>  }
>
>  static void adjust_git_path(const struct repository *repo,
> +                           const struct worktree *wt,
>                             struct strbuf *buf, int git_dir_len)
>  {
>         const char *base = buf->buf + git_dir_len;
>         if (is_dir_file(base, "info", "grafts"))
>                 strbuf_splice(buf, 0, buf->len,
>                               repo->graft_file, strlen(repo->graft_file));
> -       else if (!strcmp(base, "index"))
> +       /*
> +        * Only try to replace the path '$gitdir/index' with the index file
> +        * recorded in the repository when not constructing a path for a
> +        * worktree.  This way we can retrieve the correct path to a particular
> +        * worktree's index file.
> +        */
> +       else if (!wt && !strcmp(base, "index"))
>                 strbuf_splice(buf, 0, buf->len,
>                               repo->index_file, strlen(repo->index_file));
>         else if (dir_prefix(base, "objects"))
> @@ -411,7 +418,7 @@ static void do_git_path(const struct repository *repo,
>                 strbuf_addch(buf, '/');
>         gitdir_len = buf->len;
>         strbuf_vaddf(buf, fmt, args);
> -       adjust_git_path(repo, buf, gitdir_len);
> +       adjust_git_path(repo, wt, buf, gitdir_len);
>         strbuf_cleanup_path(buf);
>  }
>
> --
> 2.13.1.611.g7e3b11ae1-goog
>