(select-safe-coding-system): If

DEFAULT-CODING-SYSTEM is not specified, also check the most
preferred coding-system if buffer-file-coding-system is
`undecided'.  From handa.

2 files changed, 45 insertions, 13 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index ed96ee213a2..322005b1794 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,10 @@
+2000-06-08  Dave Love  <fx@gnu.org>
+
+        * international/mule-cmds.el (select-safe-coding-system): If
+        DEFAULT-CODING-SYSTEM is not specified, also check the most
+        preferred coding-system if buffer-file-coding-system is
+        `undecided'.  From Handa.
+
 2000-06-08  Kenichi Handa  <handa@etl.go.jp>
 
         * international/mule.el
diff --git a/lisp/international/mule-cmds.el b/lisp/international/mule-cmds.el
index 33f0da1311e..25a588ef2fb 100644
--- a/lisp/international/mule-cmds.el
+++ b/lisp/international/mule-cmds.el
@@ -463,7 +463,9 @@ checked at first.  If omitted, buffer-file-coding-system of the
 current buffer is used.
 
 If the text can be encoded safely by DEFAULT-CODING-SYSTEM, it is
-returned without any user interaction.
+returned without any user interaction.  DEFAULT-CODING-SYSTEM may also
+be a list, from which the first coding system that can safely encode the
+text is chosen, if any can.
 
 Kludgy feature: if FROM is a string, the string is the target text,
 and TO is ignored."
@@ -471,15 +473,38 @@ and TO is ignored."
       (setq default-coding-system buffer-file-coding-system))
   (let* ((charsets (if (stringp from) (find-charset-string from)
                      (find-charset-region from to)))
-         (safe-coding-systems (find-coding-systems-for-charsets charsets)))
+         (safe-coding-systems (find-coding-systems-for-charsets charsets))
+         (coding-system t)              ; t means not yet decided.
+         eol-type)
     (if (or (not enable-multibyte-characters)
-            (eq (car safe-coding-systems) 'undecided)
-            (eq default-coding-system 'no-conversion)
+            (eq (car safe-coding-systems) 'undecided))
+        ;; As the text doesn't contain a multibyte character, we can
+        ;; use any coding system.
+        (setq coding-system default-coding-system)
+
+      ;; Try the default.  If the default is nil or undecided, try the
+      ;; most prefered one or one of its subsidiaries that converts
+      ;; EOL as the same way as the default.
+      (if (or (not default-coding-system)
+              (eq (coding-system-base default-coding-system) 'undecided))
+          (progn
+            (setq eol-type
+                  (and default-coding-system
+                       (coding-system-eol-type default-coding-system)))
+            (setq default-coding-system
+                  (symbol-value (car coding-category-list)))
+            (or (not eol-type)
+                (vectorp eol-type)
+                (setq default-coding-system
+                      (coding-system-change-eol-conversion
+                       default-coding-system eol-type)))))
+      (if (or (eq default-coding-system 'no-conversion)
             (and default-coding-system
                  (memq (coding-system-base default-coding-system)
                        safe-coding-systems)))
-        default-coding-system
+          (setq coding-system default-coding-system)))
 
+    (when (eq coding-system t)
       ;; At first, change each coding system to the corresponding
       ;; mime-charset name if it is also a coding system.
       (let ((l safe-coding-systems)
@@ -565,17 +590,17 @@ Please select one from the following safe coding systems:\n"
                                       (car safe-coding-systems))
                               safe-names nil t nil nil
                               (car (car safe-names)))))
-                  (setq last-coding-system-specified (intern name))
-                  (if (integerp (coding-system-eol-type default-coding-system))
-                      (setq last-coding-system-specified
-                            (coding-system-change-eol-conversion
-                             last-coding-system-specified
-                             (coding-system-eol-type default-coding-system))))
-                  last-coding-system-specified))
+                  (setq last-coding-system-specified (intern name)
+                        coding-system last-coding-system-specified)
+                  (or (not eol-type)
+                      (vectorp eol-type)
+                      (setq coding-system (coding-system-change-eol-conversion
+                                           coding-system eol-type)))))
             (kill-buffer "*Warning*")
             (while overlays
               (delete-overlay (car overlays))
-              (setq overlays (cdr overlays)))))))))
+              (setq overlays (cdr overlays)))))))
+    coding-system))
 
 (setq select-safe-coding-system-function 'select-safe-coding-system)