bug#27391: 25.2.50; utf-8 coding cookie is not applied on some specific markdown file

[Philipp Stephani]

Philipp Stephani <p.stephani2@gmail.com> schrieb am Fr., 16. Juni 2017 um 23:39 Uhr:

Philipp Stephani <p.stephani2@gmail.com> schrieb am Fr., 16. Juni 2017 um 23:34 Uhr:

Vincent Belaïche <vincent.belaiche@gmail.com> schrieb am Fr., 16. Juni 2017 um 23:28 Uhr:

Le 16/06/2017 à 21:37, Vincent Belaïche a écrit :
>
>
> Le 16/06/2017 à 21:15, Vincent Belaïche a écrit :
>>

[...]

>>
>>
> After some more investigation, I think that the bug is in function
> insert-file-contents of fileio.c which is the one that decide and sets
> the coding system well before the other local variables are looked into.

After some more investigation, in the end the find-auto-coding of
mule.el is what is called to detect the coding. This function calls some
re-coding regexp.

Here is a test function defining the same regexp.


(defun doit ()
  (interactive)
  (let* ((prefix (regexp-quote "[comment]: # ("))
         (suffix (regexp-quote ")"))
         (re-coding
          (concat
           "[\r\n]" prefix
           ;; N.B. without the \n below, the regexp can
           ;; eat newlines.
           "[ \t]*coding[ \t]*:[ \t]*\\([^ \t\r\n]+\\)[ \t]*"
           suffix "[\r\n]")))
    (message (if (looking-at re-coding) "ok" "nak"))))

I tried it with point at end of line

[comment]: # ( Local Variables: )

and it answered "ok". Now I defined this with re-search-forward instead
of looking-at:

(defun doit ()
  (interactive)
  (let* ((prefix (regexp-quote "[comment]: # ("))
         (suffix (regexp-quote ")"))
         (re-coding
          (concat
           "[\r\n]" prefix
           ;; N.B. without the \n below, the regexp can
           ;; eat newlines.
           "[ \t]*coding[ \t]*:[ \t]*\\([^ \t\r\n]+\\)[ \t]*"
           suffix "[\r\n]")))
    (message (if (re-search-forward re-coding nil t) "ok" "nak"))))

I placed the point before the coding: line, and I also got answer "ok"

So I don't think that the regexp as such is to blame. Something else
seems to happen. It is too late now, I need to go to bed...

  Vincent.

I think it's actually the regexp that searches for "Local Variables". The following minimal example fails for me:

(with-temp-buffer

  (insert "

[comment]: # ( Local Variables: )

[comment]: # ( coding: utf-8 )

[comment]: # ( End: )

")

(goto-char (point-min))

(re-search-forward

 "[\r\n]\\([^[\r\n]*\\)[ \t]*Local Variables:[ \t]*\\([^\r\n]*\\)[\r\n]"))

Does anybody know why the second character range says [^[\r\n] instead of  [^\r\n]? This seems to explicitly exclude a leading [.

If this is a typo, then here's a patch. 

0001-Allow-local-variables-section-to-begin-with-a-square-b.txt
Description: Text document