Re: [PATCH 7/8] worktree: generalize candidate worktree path validation

[Junio C Hamano <gitster@pobox.com>]

Eric Sunshine <sunshine@sunshineco.com> writes:

> "git worktree add" checks that the specified path is a valid location
> for a new worktree by ensuring that the path does not already exist and
> is not already registered to another worktree (a path can be registered
> but missing, for instance, if it resides on removable media). Since "git
> worktree add" is not the only command which should perform such
> validation ("git worktree move" ought to also), generalize the the
> validation function for use by other callers, as well.

Makes sense.

> -	validate_worktree_add(path, opts);
> +	worktrees = get_worktrees(0);
> +	check_candidate_path(path, opts->force, worktrees, "add");
> +	free_worktrees(worktrees);
> +	worktrees = NULL;

It is somewhat unsatisfying that the libified helper still signals
its displeasure by dying, but a faithful conversion that can be
cleaned up later (if we wanted to) like this step is easier to
reason about.