Fix the "C-x =" display of the character info for LRE, LRO, RLE, and RLO.

 lisp/simple.el (what-cursor-position): Fix the display of the
 character info for LRE, LRO, RLE, and RLO characters, by appending a
 PDF to them.

2 files changed, 19 insertions, 4 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 1ec96318116..39f13eb8db8 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,8 @@
+2011-10-13  Eli Zaretskii  <eliz@gnu.org>
+
+        * simple.el (what-cursor-position): Fix the display of the
+        character info for LRE, LRO, RLE, and RLO characters.
+
 2011-10-13  Stefan Monnier  <monnier@iro.umontreal.ca>
 
         * emacs-lisp/timer.el (with-timeout): Make sure we cancel the timer
diff --git a/lisp/simple.el b/lisp/simple.el
index af6d855d9c0..6d0e7543549 100644
--- a/lisp/simple.el
+++ b/lisp/simple.el
@@ -1050,6 +1050,16 @@ In addition, with prefix argument, show details about that character
 in *Help* buffer.  See also the command `describe-char'."
   (interactive "P")
   (let* ((char (following-char))
+         ;; If the character is one of LRE, LRO, RLE, RLO, it will
+         ;; start a directional embedding, which could completely
+         ;; disrupt the rest of the line (e.g., RLO will display the
+         ;; rest of the line right-to-left).  So we put an invisible
+         ;; PDF character after these characters, to end the
+         ;; embedding, which eliminates any effects on the rest of the
+         ;; line.
+         (pdf (if (memq char '(?\x202a ?\x202b ?\x202d ?\x202e))
+                  (propertize (string ?\x202c) 'invisible t)
+                ""))
          (beg (point-min))
          (end (point-max))
          (pos (point))
@@ -1109,18 +1119,18 @@ in *Help* buffer.  See also the command `describe-char'."
             ;; We show the detailed information about CHAR.
             (describe-char (point)))
         (if (or (/= beg 1) (/= end (1+ total)))
-            (message "Char: %s %s point=%d of %d (%d%%) <%d-%d> column=%d%s"
+            (message "Char: %s%s %s point=%d of %d (%d%%) <%d-%d> column=%d%s"
                      (if (< char 256)
                          (single-key-description char)
                        (buffer-substring-no-properties (point) (1+ (point))))
-                     encoding-msg pos total percent beg end col hscroll)
-          (message "Char: %s %s point=%d of %d (%d%%) column=%d%s"
+                     pdf encoding-msg pos total percent beg end col hscroll)
+          (message "Char: %s%s %s point=%d of %d (%d%%) column=%d%s"
                    (if enable-multibyte-characters
                        (if (< char 128)
                            (single-key-description char)
                          (buffer-substring-no-properties (point) (1+ (point))))
                      (single-key-description char))
-                   encoding-msg pos total percent col hscroll))))))
+                   pdf encoding-msg pos total percent col hscroll))))))
 
 ;; Initialize read-expression-map.  It is defined at C level.
 (let ((m (make-sparse-keymap)))