Re: locate-dominating-file calls `stat' too eagerly

[Stefan Monnier]

> This fragment from locate-dominating-file:
>       (while (and dir
>                   ;; As a heuristic, we stop looking up the hierarchy of
>                   ;; directories as soon as we find a directory belonging to
>                   ;; another user.  This should save us from looking in
>                   ;; things like /net and /afs.  This assumes that all the
>                   ;; files inside a project belong to the same user.
>                   (let ((prev-user user))
>                     (setq user (nth 2 (file-attributes dir)))
>                     (or (null prev-user) (equal user prev-user))))
>         (if (setq files (and (file-directory-p dir)
>                              (directory-files dir 'full regexp)))
>             (throw 'found (car files))
>           (if (equal dir
>                      (setq dir (file-name-directory
>                                 (directory-file-name dir))))
>               (setq dir nil))))

> repeatedly calls file-directory-p, even after file-directory-p already
> returned non-nil, which means that thereafter anything that
> file-name-directory returns will also necessarily be a directory.
> That looks like inefficiency, doesn't it?  Here's the modification I
> propose:

Wouldn't it be simpler to wrap the `directroy-files' call inside
a condition-case and drop the file-directory-p altogether?


        Stefan