file coding system for require'd .el files depends on locale

[David Reitter <david.reitter@gmail.com>]

I've encountered an issue with a source file being loaded by  
"require" using an coding system that depends on the machine's locale.
The source file was decoded with the wrong coding system on a  
Japanese (OS X) machine and, subsequently, produced the error below.

I find this behavior inconvenient, because a "require" or "load"  
often applies to files developed and tested under a different locale,  
where the coding system is guessed correctly. I would like to have a  
guarantee that my source file is decoded consistently, no matter what  
the locale is.

The error that occurred was:

Debugger entered--Lisp error: (invalid-read-syntax ") or . in a vector")
   eval-buffer(#<buffer  *load*> nil "/Users/dr/A.app/Contents/ 
Resources/site-lisp/macosx/emulate-mac-keyboard-mode.el" n$
   (let ((load-file-name fullname) (set-auto-coding-for-load t)  
(inhibit-file-name-operation nil)) (with-current-buffer b$
   (unwind-protect (let (... ... ...) (with-current-buffer  
buffer ... ... ...) (eval-buffer buffer nil ... nil t)) (let ($
   (let* ((buffer ...) (load-in-progress t) (source ...)) (unless  
nomessage (if source ... ...)) (when purify-flag (push $
   (if (null (file-readable-p fullname)) (and (null noerror)  
(signal ... ...)) (let* (... ... ...) (unless nomessage ...)$
   load-with-code-conversion("/Users/dr/A.app/Contents/Resources/site- 
lisp/macosx/emulate-mac-keyboard-mode.el" "/Users/d$
   require(emulate-mac-keyboard-mode)


If the file is visited manually on the Japanese machine, buffer-file- 
coding-system  is `japanese-shift-jis-unix'.
On my locale, it is `iso-latin-1-unix' (correct).

The output of C-h C on the Japanese machine is attached to the end of  
this message.

The file being loaded can be inspected here:
http://aquamacs.cvs.sourceforge.net/*checkout*/aquamacs/aquamacs/src/ 
site-lisp/macosx/emulate-mac-keyboard-mode.el

Finally, my workaround for this is to do

  (let ((coding-system-for-read 'iso-latin-1-unix))
     (require 'emulate-mac-keyboard-mode))

I guess I could have defined the coding system in the file directly,  
or I could have byte-compiled it.

Thanks to Carson Reynolds at U Tokyo for helping me track this down.


Coding system for saving this buffer:
   - -- undecided-unix

Default coding system (for new files):
   E -- euc-jp-unix (alias of japanese-iso-8bit-unix)

Coding system for keyboard input:
   M -- mac-roman

Coding system for terminal output:
   1 -- iso-8859-1 (alias of iso-latin-1)

Defaults for subprocess I/O:
   decoding: E -- japanese-iso-8bit (alias: euc-japan-1990 euc-japan  
euc-jp)

   encoding: E -- japanese-iso-8bit (alias: euc-japan-1990 euc-japan  
euc-jp)


Priority order for recognizing coding systems when reading files:
   1. japanese-iso-8bit (alias: euc-japan-1990 euc-japan euc-jp)
   2. iso-2022-jp (alias: junet)
   3. japanese-shift-jis (alias: shift_jis sjis cp932)
   4. iso-2022-jp-2
   5. iso-latin-1 (alias: iso-8859-1 latin-1)
   6. mule-utf-8 (alias: utf-8)
   7. mule-utf-16be-with-signature (alias: utf-16be-with-signature  
mule-utf-16-be utf-16-be)
   8. mule-utf-16le-with-signature (alias: utf-16le-with-signature  
mule-utf-16-le utf-16-le)
   9. iso-2022-7bit
   10. iso-2022-8bit-ss2
   11. emacs-mule
   12. raw-text
   13. chinese-big5 (alias: big5 cn-big5 cp950)
   14. no-conversion


   Other coding systems cannot be distinguished automatically
   from these, and therefore cannot be recognized automatically
   with the present coding system priorities.

   The following are decoded correctly but recognized as iso-2022-jp-2:
     iso-2022-7bit-ss2 iso-2022-7bit-lock iso-2022-7bit-lock-ss2  
iso-2022-cn iso-2022-cn-ext iso-2022-kr

Particular coding systems specified for certain file names:

   OPERATION     TARGET PATTERN          CODING SYSTEM(s)
   ---------     --------------          ----------------
   File I/O      "\\.dz\\'"              (no-conversion . no-conversion)
                 "\\.g?z\\(~\\|\\.~[0-9]+~\\)?\\'"
                                         (no-conversion . no-conversion)
                 "\\.tgz\\'"             (no-conversion . no-conversion)
                 "\\.tbz\\'"             (no-conversion . no-conversion)
                 "\\.bz2\\(~\\|\\.~[0-9]+~\\)?\\'"
                                         (no-conversion . no-conversion)
                 "\\.Z\\(~\\|\\.~[0-9]+~\\)?\\'"
                                         (no-conversion . no-conversion)
                 "\\.elc\\'"             (emacs-mule . emacs-mule)
                 "\\.utf\\(-8\\)?\\'"    utf-8
                 "\\(\\`\\|/\\)loaddefs.el\\'"
                                         (raw-text . raw-text-unix)
                 "\\.tar\\'"             (no-conversion . no-conversion)
                 "\\.po[tx]?\\'\\|\\.po\\."
                                         po-find-file-coding-system
                 "\\.\\(tex\\|ltx\\|dtx\\|drv\\)\\'"
                                         latexenc-find-file-coding- 
system
                 ""                      (undecided)
   Process I/O   nothing specified
   Network I/O   nothing specified