diff -r 2f6f6f7551ca -r 32102edaa81b web/wp-includes/Text/Diff/Renderer/inline.php
--- a/web/wp-includes/Text/Diff/Renderer/inline.php	Thu Sep 16 15:45:36 2010 +0000
+++ b/web/wp-includes/Text/Diff/Renderer/inline.php	Mon Nov 19 18:26:13 2012 +0100
@@ -2,9 +2,7 @@
 /**
  * "Inline" diff renderer.
  *
- * $Horde: framework/Text_Diff/Diff/Renderer/inline.php,v 1.21 2008/01/04 10:07:51 jan Exp $
- *
- * Copyright 2004-2008 The Horde Project (http://www.horde.org/)
+ * Copyright 2004-2010 The Horde Project (http://www.horde.org/)
  *
  * See the enclosed file COPYING for license information (LGPL). If you did
  * not receive this file, see http://opensource.org/licenses/lgpl-license.php.
@@ -30,42 +28,65 @@
 
     /**
      * Number of leading context "lines" to preserve.
+     *
+     * @var integer
      */
     var $_leading_context_lines = 10000;
 
     /**
      * Number of trailing context "lines" to preserve.
+     *
+     * @var integer
      */
     var $_trailing_context_lines = 10000;
 
     /**
      * Prefix for inserted text.
+     *
+     * @var string
      */
     var $_ins_prefix = '<ins>';
 
     /**
      * Suffix for inserted text.
+     *
+     * @var string
      */
     var $_ins_suffix = '</ins>';
 
     /**
      * Prefix for deleted text.
+     *
+     * @var string
      */
     var $_del_prefix = '<del>';
 
     /**
      * Suffix for deleted text.
+     *
+     * @var string
      */
     var $_del_suffix = '</del>';
 
     /**
      * Header for each change block.
+     *
+     * @var string
      */
     var $_block_header = '';
 
     /**
+     * Whether to split down to character-level.
+     *
+     * @var boolean
+     */
+    var $_split_characters = false;
+
+    /**
      * What are we currently splitting on? Used to recurse to show word-level
-     * changes.
+     * or character-level changes.
+     *
+     * @var string
      */
     var $_split_level = 'lines';
 
@@ -85,10 +106,10 @@
             array_walk($lines, array(&$this, '_encode'));
         }
 
-        if ($this->_split_level == 'words') {
+        if ($this->_split_level == 'lines') {
+            return implode("\n", $lines) . "\n";
+        } else {
             return implode('', $lines);
-        } else {
-            return implode("\n", $lines) . "\n";
         }
     }
 
@@ -110,8 +131,13 @@
 
     function _changed($orig, $final)
     {
-        /* If we've already split on words, don't try to do so again - just
-         * display. */
+        /* If we've already split on characters, just display. */
+        if ($this->_split_level == 'characters') {
+            return $this->_deleted($orig)
+                . $this->_added($final);
+        }
+
+        /* If we've already split on words, just display. */
         if ($this->_split_level == 'words') {
             $prefix = '';
             while ($orig[0] !== false && $final[0] !== false &&
@@ -130,15 +156,23 @@
         /* Non-printing newline marker. */
         $nl = "\0";
 
-        /* We want to split on word boundaries, but we need to
-         * preserve whitespace as well. Therefore we split on words,
-         * but include all blocks of whitespace in the wordlist. */
-        $diff = new Text_Diff($this->_splitOnWords($text1, $nl),
-                              $this->_splitOnWords($text2, $nl));
+        if ($this->_split_characters) {
+            $diff = new Text_Diff('native',
+                                  array(preg_split('//', $text1),
+                                        preg_split('//', $text2)));
+        } else {
+            /* We want to split on word boundaries, but we need to preserve
+             * whitespace as well. Therefore we split on words, but include
+             * all blocks of whitespace in the wordlist. */
+            $diff = new Text_Diff('native',
+                                  array($this->_splitOnWords($text1, $nl),
+                                        $this->_splitOnWords($text2, $nl)));
+        }
 
         /* Get the diff in inline format. */
-        $renderer = new Text_Diff_Renderer_inline(array_merge($this->getParams(),
-                                                              array('split_level' => 'words')));
+        $renderer = new Text_Diff_Renderer_inline
+            (array_merge($this->getParams(),
+                         array('split_level' => $this->_split_characters ? 'characters' : 'words')));
 
         /* Run the diff and get the output. */
         return str_replace($nl, "\n", $renderer->render($diff)) . "\n";