Bug in message-draft-coding-system

Bug in message-draft-coding-system

[Shenghuo ZHU]

"coding-system-p" seems not work correctly in XEmacs 20.4. For
example, (coding-system-p 'binary) returns nil. Is it a bug of XEmacs?

Because of this, message-draft-coding-system is set to nil, which
should be escape-quoted.

A patch is attached.

-- 
Shenghuo

Thu Jan 28 01:38:34 1999  Shenghuo ZHU  <zsh@cs.rochester.edu>

	* message.el (message-draft-coding-system): Check coding-system.
	* mm-util.el (mm-text-coding-system): Ditto.

--- message.el	1999/01/28 06:34:59	1.1
+++ message.el	1999/01/28 06:35:39
@@ -884,7 +884,7 @@
   (cond
    ((not (fboundp 'coding-system-p)) nil)
    ((coding-system-p 'emacs-mule) 'emacs-mule)
-   ((coding-system-p 'escape-quoted) 'escape-quoted)
+   ((memq 'escape-quoted (mm-get-coding-system-list)) 'escape-quoted)
    ((coding-system-p 'no-conversion) 'no-conversion)
    (t nil))
   "Coding system to compose mail.")

--- mm-util.el	1999/01/28 06:32:51	1.1
+++ mm-util.el	1999/01/28 06:33:09
@@ -39,7 +39,7 @@
   (cond
    ((not (fboundp 'coding-system-p)) nil)
    (mm-running-xemacs  ;; XEmacs
-    (and (coding-system-p 'no-conversion) 'no-conversion))
+    'no-conversion)
    (mm-running-ntemacs ;; NTEmacs
     (and (coding-system-p 'raw-text-dos) 'raw-text-dos))
    ((coding-system-p 'raw-text) 'raw-text) ;; Emacs

Re: Bug in message-draft-coding-system

[Hrvoje Niksic]

Shenghuo ZHU <zsh@cs.rochester.edu> writes:

> "coding-system-p" seems not work correctly in XEmacs 20.4. For
> example, (coding-system-p 'binary) returns nil. Is it a bug of
> XEmacs?

It's not a bug.  As the documentation says:

    Return t if OBJECT is a coding system.
    A coding system is an object that defines how text containing multiple
    character sets is encoded into a stream of (typically 8-bit) bytes.
    [...]

You probably want to use `find-coding-system' or `get-coding-system'
(the difference between the two being that the latter signals an error 
when the symbol doesn't correspond to a coding-system.)