Coding system detection: Emacs 23 vs. 22

[Reiner Steib]

Hi,

when opening the attached file (see attachment `ae.el.gz'), thee
coding system detection of Emacs 23 and 22 give different results:

- Emacs 22 (both, Emacs 21.1 and the current Emacs 22 branch) says
  emacs-mule-unix.  (The file was created with Emacs 22)

- Emacs 23, says iso-latin-1-unix

The real problem with this is that my Gnus score files of Emacs 22 no
longer work with Emacs 23 if the score entry (subject, author, ...)
contains a non-ascii character.


Expected behavior:

Emacs 23 should detect that the attached file is not iso-latin-1 (even
`file' detects this) but emacs-mule.


To reproduce:

Save attachment to /tmp/ae.el.gz

$ gunzip /tmp/ae.el.gz

$ file /tmp/ae.el 
/tmp/ae.el: Non-ISO extended-ASCII text
$ /usr/bin/emacs --batch -Q /tmp/ae.el --eval \
  '(message "buffer-file-coding-system=%s, %s" buffer-file-coding-system \
  emacs-version)' -kill
buffer-file-coding-system=emacs-mule-unix, 22.1.1
$ cvs-EMACS_22_BASE/i686/src/emacs --batch -Q /tmp/ae.el --eval \
  '(message "buffer-file-coding-system=%s, %s" buffer-file-coding-system \
  emacs-version)' -kill
buffer-file-coding-system=emacs-mule-unix, 22.1.92.2
$ cvs-HEAD/i686/src/emacs --batch -Q /tmp/ae.el --eval \
  '(message "buffer-file-coding-system=%s, %s" buffer-file-coding-system \
  emacs-version)' -kill
buffer-file-coding-system=iso-latin-1-unix, 23.0.60.2

Bye, Reiner.
-- 
       ,,,
      (o o)
---ooO-(_)-Ooo---  |  PGP key available  |  http://rsteib.home.pages.de/

ae.el.gz
Description: GNU Zip compressed data