From: Eli Zaretskii <eliz@gnu.org>
Date: Mon, 5 Dec 2011 17:46:27 +0000 (+0200)
Subject: Fix "C-x =" wrt display of strong RTL characters and directional controls.
X-Git-Tag: emacs-pretest-24.0.93~222
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=71cc0b7439279dacaa9fa8a6dd97fb073c46551b;p=emacs.git

Fix "C-x =" wrt display of strong RTL characters and directional controls.

 lisp/descr-text.el (describe-char): Fix display of strong
 right-to-left characters and directional embeddings and overrides.
 lisp/simple.el (what-cursor-position): Fix display of codepoints of
 strong right-to-left characters by appending LRM.
---

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index ff9a8ad19df..8cb089d523e 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,11 @@
+2011-12-05  Eli Zaretskii  <eliz@gnu.org>
+
+	* descr-text.el (describe-char): Fix display of strong
+	right-to-left characters and directional embeddings and overrides.
+
+	* simple.el (what-cursor-position): Fix display of codepoints of
+	strong right-to-left characters.
+
 2011-12-05  Chong Yidong  <cyd@gnu.org>
 
 	* faces.el (read-color): Doc fix.
diff --git a/lisp/descr-text.el b/lisp/descr-text.el
index f285fe42332..47f96e8d68f 100644
--- a/lisp/descr-text.el
+++ b/lisp/descr-text.el
@@ -422,6 +422,20 @@ as well as widgets, buttons, overlays, and text properties."
               (setq charset (char-charset char)
                     code (encode-char char charset)))
         (setq code char))
+      (cond
+       ;; Append a PDF character to directional embeddings and
+       ;; overrides, to prevent potential messup of the following
+       ;; text.
+       ((memq char '(?\x202a ?\x202b ?\x202d ?\x202e))
+	(setq char-description
+	      (concat char-description
+		      (propertize (string ?\x202c) 'invisible t))))
+       ;; Append a LRM character to any strong character to avoid
+       ;; messing up the numerical codepoint.
+       ((memq (get-char-code-property char 'bidi-class) '(R AL))
+	(setq char-description
+	      (concat char-description
+		      (propertize (string ?\x200e) 'invisible t)))))
       (when composition
         ;; When the composition is trivial (i.e. composed only with the
         ;; current character itself without any alternate characters),
diff --git a/lisp/simple.el b/lisp/simple.el
index b718546248b..e9d88a210cf 100644
--- a/lisp/simple.el
+++ b/lisp/simple.el
@@ -1052,16 +1052,23 @@ 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)
-		""))
+	 (bidi-fixer
+	  (cond ((memq char '(?\x202a ?\x202b ?\x202d ?\x202e))
+		 ;; 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.
+		 (propertize (string ?\x202c) 'invisible t))
+		;; Strong right-to-left characters cause reordering of
+		;; the following numerical characters which show the
+		;; codepoint, so append LRM to countermand that.
+		((memq (get-char-code-property char 'bidi-class) '(R AL))
+		 (propertize (string ?\x200e) 'invisible t))
+		(t
+		 "")))
 	 (beg (point-min))
 	 (end (point-max))
          (pos (point))
@@ -1125,14 +1132,15 @@ in *Help* buffer.  See also the command `describe-char'."
 		     (if (< char 256)
 			 (single-key-description char)
 		       (buffer-substring-no-properties (point) (1+ (point))))
-		     pdf encoding-msg pos total percent beg end col hscroll)
+		     bidi-fixer
+		     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))
-		   pdf encoding-msg pos total percent col hscroll))))))
+		   bidi-fixer encoding-msg pos total percent col hscroll))))))
 
 ;; Initialize read-expression-map.  It is defined at C level.
 (let ((m (make-sparse-keymap)))