Prevent bidi reordering of rows and keys in the quail layout display.

 lisp/international/quail.el (quail-insert-kbd-layout): Insert
 invisible LRM characters before each character in a keyboard
 layout cell, to prevent their reordering by bidi display engine.
 For details, see the discussion in
 http://lists.gnu.org/archive/html/emacs-devel/2012-03/msg00085.html.

2 files changed, 22 insertions, 5 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 7673b1fc429..0e931572f01 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,11 @@
+2012-03-08  Eli Zaretskii  <eliz@gnu.org>
+
+        * international/quail.el (quail-insert-kbd-layout): Insert
+        invisible LRM characters before each character in a keyboard
+        layout cell, to prevent their reordering by bidi display engine.
+        For details, see the discussion in
+        http://lists.gnu.org/archive/html/emacs-devel/2012-03/msg00085.html.
+
 2012-03-08  Alan Mackenzie  <acm@muc.de>
 
         * progmodes/cc-cmds.el (c-mark-function): Make it leave a mark at
diff --git a/lisp/international/quail.el b/lisp/international/quail.el
index 48aa013c674..4e068741e43 100644
--- a/lisp/international/quail.el
+++ b/lisp/international/quail.el
@@ -833,7 +833,15 @@ The format of KBD-LAYOUT is the same as `quail-keyboard-layout'."
         (insert bar)
         (if (= (if (stringp lower) (string-width lower) (char-width lower)) 1)
             (insert " "))
-        (insert lower upper)
+        ;; Insert invisible LRM characters to force each keyboard row
+        ;; be rendered left to right, and also to prevent reordering of
+        ;; individual characters within each cell.  See
+        ;; http://lists.gnu.org/archive/html/emacs-devel/2012-03/msg00085.html
+        ;; for the reasons.
+        (insert (propertize (string ?\x200e) 'invisible t))
+        (insert lower)
+        (insert (propertize (string ?\x200e) 'invisible t))
+        (insert upper)
         (if (= (if (stringp upper) (string-width upper) (char-width upper)) 1)
             (insert " "))
         (setq i (+ i 2))
@@ -849,20 +857,21 @@ The format of KBD-LAYOUT is the same as `quail-keyboard-layout'."
         ;;(delete-region pos (point)))
         (let ((from1 100) (to1 0) from2 to2)
           (while (not (eobp))
-            (if (looking-at "[| ]*$")
+            (if (looking-at "[| \u200e]*$")
                 ;; The entire row is blank.
                 (delete-region (point) (match-end 0))
               ;; Delete blank key columns at the head.
-              (if (looking-at " *\\(|    \\)+")
+              (if (looking-at " *\\(| \u200e \u200e  \\)+")
                   (subst-char-in-region (point) (match-end 0) ?| ? ))
               ;; Delete blank key columns at the tail.
-              (if (re-search-forward "\\(    |\\)+$" (line-end-position) t)
+              (if (re-search-forward "\\( \u200e \u200e  |\\)+$"
+                                     (line-end-position) t)
                   (delete-region (match-beginning 0) (point)))
               (beginning-of-line))
             ;; Calculate the start and end columns of a horizontal line.
             (if (eolp)
                 (setq from2 from1 to2 to1)
-              (skip-chars-forward " ")
+              (skip-chars-forward " \u200e")
               (setq from2 (current-column))
               (end-of-line)
               (setq to2 (current-column))