(find-new-buffer-file-coding-system): Reflect

text coding part of default-buffer-file-coding-system to
buffer-file-coding-system when buffer-file-coding-system is
not locally set and ASCII only text is read.

diff --git a/lisp/international/mule.el b/lisp/international/mule.el
index 66e82575ec428e51bf7acd4853331c5d3c8b0cac..9eeeb30d659672e0d699463a020480672f97a5f3 100644 (file)
--- a/lisp/international/mule.el
+++ b/lisp/international/mule.el
@@ -728,30 +728,27 @@ The local variable `buffer-file-coding-system' of the current buffer
 is set to the returned value.
 Return nil if there's no need of setting new buffer-file-coding-system."
   (let (local-coding local-eol
-       found-eol
+       found-coding found-eol
        new-coding new-eol)
     (if (null coding)
        ;; Nothing found about coding.
        nil
 
-      ;; Get information of the current local value of
-      ;; `buffer-file-coding-system' in LOCAL-EOL and LOCAL-CODING.
-      (if (local-variable-p 'buffer-file-coding-system)
-         ;; Something already set locally.
-         (progn
-           (setq local-eol (coding-system-eol-type buffer-file-coding-system))
-           (if (null (numberp local-eol))
-               ;; But eol-type is not yet set.
-               (setq local-eol nil))
-           (if (null (eq (coding-system-type buffer-file-coding-system) t))
-               ;; This is not `undecided'.
-               (progn
-                 (setq local-coding buffer-file-coding-system)
-                 (while (symbolp (get local-coding 'coding-system))
-                   (setq local-coding (get local-coding 'coding-system))))
-             )))
-
-      (if (and local-eol local-coding)
+      ;; Get information of `buffer-file-coding-system' in LOCAL-EOL
+      ;; and LOCAL-CODING.
+      (setq local-eol (coding-system-eol-type buffer-file-coding-system))
+      (if (null (numberp local-eol))
+         ;; But eol-type is not yet set.
+         (setq local-eol nil))
+      (when (and buffer-file-coding-system
+                (not (eq (coding-system-type buffer-file-coding-system) t)))
+       ;; This is not `undecided'.
+       (setq local-coding buffer-file-coding-system)
+       (while (symbolp (get local-coding 'coding-system))
+         (setq local-coding (get local-coding 'coding-system))))
+
+      (if (and (local-variable-p 'buffer-file-coding-system)
+              local-eol local-coding)
          ;; The current buffer has already set full coding-system, we
          ;; had better not change it.
          nil
@@ -760,15 +757,31 @@ Return nil if there's no need of setting new buffer-file-coding-system."
        (if (null (numberp found-eol))
            ;; But eol-type is not found.
            (setq found-eol nil))
+       (unless (eq (coding-system-type coding) t)
+         ;; This is not `undecided'.
+         (setq found-coding coding)
+         (while (symbolp (get found-coding 'coding-system))
+           (setq found-coding (get found-coding 'coding-system))))
 
        ;; The local setting takes precedence over the found one.
-       (setq new-coding (or local-coding coding))
-       (setq new-eol (or local-eol found-eol))
-       (if (and (numberp new-eol)
-                (vectorp (coding-system-eol-type new-coding)))
-           (setq new-coding
-                 (aref (coding-system-eol-type new-coding) new-eol)))
-       new-coding))))
+       (setq new-coding (or (and (local-variable-p 'buffer-file-coding-system)
+                                 local-coding)
+                            found-coding
+                            local-coding))
+       (setq new-eol (or (and (local-variable-p 'buffer-file-coding-system)
+                              local-eol)
+                         found-eol
+                         local-eol))
+       (when (numberp new-eol)
+         (or new-coding
+             (setq new-coding 'undecided))
+         (if (vectorp (coding-system-eol-type new-coding))
+             (setq new-coding
+                   (aref (coding-system-eol-type new-coding) new-eol))))
+       ;; Return a new coding system only when it is different from
+       ;; the current one.
+       (if (not (eq buffer-file-coding-system new-coding))
+           new-coding)))))
 
 (defun modify-coding-system-alist (target-type regexp coding-system)
   "Modify one of look up tables for finding a coding system on I/O operation.