From c556c89627321c4d10610a210129ef32dd2a46af Mon Sep 17 00:00:00 2001
From: Sam Stephenson <sam@37signals.com>
Date: Sat, 27 Jan 2007 18:33:03 +0000
Subject: [PATCH] prototype: Improve performance of String.prototype.escapeHTML
 by using a cached div and text node.  Closes #6937.

---
 CHANGELOG     |  2 ++
 src/string.js | 14 ++++++++++----
 2 files changed, 12 insertions(+), 4 deletions(-)

diff --git a/CHANGELOG b/CHANGELOG
index f3e18b8..2d19d2d 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,5 +1,7 @@
 *SVN*
 
+* Improve performance of String.prototype.escapeHTML by using a cached div and text node.  Closes #6937.  [altblue]
+
 * Make setStyle() with opacity: 0 in Internet Explorer work correctly.  [Thomas Fuchs]
 
 * Form.Element.activate shouldn't raise an exception when the form or field is hidden.  [sam]
diff --git a/src/string.js b/src/string.js
index 2cf17ef..8449934 100644
--- a/src/string.js
+++ b/src/string.js
@@ -66,10 +66,9 @@ Object.extend(String.prototype, {
   },
 
   escapeHTML: function() {
-    var div = document.createElement('div');
-    var text = document.createTextNode(this);
-    div.appendChild(text);
-    return div.innerHTML;
+    var self = arguments.callee;
+    self.text.data = this;
+    return self.div.innerHTML;
   },
 
   unescapeHTML: function() {
@@ -152,6 +151,13 @@ String.prototype.gsub.prepareReplacement = function(replacement) {
 
 String.prototype.parseQuery = String.prototype.toQueryParams;
 
+Object.extend(String.prototype.escapeHTML, {
+  div:  document.createElement('div'),
+  text: document.createTextNode('')
+});
+
+with (String.prototype.escapeHTML) div.appendChild(text);
+
 var Template = Class.create();
 Template.Pattern = /(^|.|\r|\n)(#\{(.*?)\})/;
 Template.prototype = {