Re: File name completion on Mac OS X with German umlauts

[Nikolaj Schumacher <n_schumacher@web.de>]

Piet van Oostrum <piet@cs.uu.nl> wrote:

>>NS> Emacs must also be doing some normalization... switch-to-buffer
>>NS> completion works on "rückerstattung" after all.  Only `read-file-name'
>>NS> doesn't.  Hmm, maybe this /is/ an Emacs bug after all.
>
> No, it doesn't do normalization. For buffers it is the same as for
> filenames. But usually you don't have normalized buffer names (except for
> those where normalized is the same as unnormalized of course). When you
> create a file with name rückerstattung on OS X and open it from a directory
> listing (where it shows as rückerstattung) you get a buffer name
> rückerstattung. This will not complete from rü.

Ah, well, I didn't verify my claim with emacs -q.
I have

  (require 'utf-8m)
  (setq file-name-coding-system 'utf-8m))

in my .emacs, which apparently makes all of that work.


This is very interesting.  Apparently `read-file-name' doesn't use
`file-name-coding-system' when completing.

More interestingly, functions like `directory-files' do.  Thus, I was
able to hack up this alternative to `find-file':

(defun my-complete-file-name (input ignored all-p)
  (let* ((dir (or (file-name-directory input) default-directory))
         (file (file-name-nondirectory input))
         (dir-files (directory-files dir nil (concat "^" file))))
    (if all-p
        (mapcar (lambda (file) (if (file-is-dir-p file)
                                   (file-name-as-directory file)
                                 file))
                (all-completions file dir-files))
      (let ((completion (try-completion file dir-files)))
        (if (not (stringp completion))
            completion
          (setq completion (concat dir completion))
          (if (file-is-dir-p completion)
              (file-name-as-directory completion)
            completion))))))

(defun my-find-file ()
  (interactive)
  (completing-read "Find file: " 'my-complete-file-name nil nil "~/"))

It's pretty rough and much slower than the original, but it will
correctly complete "rü".


regards,
Nikolaj Schumacher