From 26b8033295c3eb4c0c37a94130684b907652dbe7 Mon Sep 17 00:00:00 2001
From: Andrew Dupont <prototype@andrewdupont.net>
Date: Tue, 27 Nov 2007 17:59:46 +0000
Subject: [PATCH] * Fix a bug in the IE-specific Element#descendantOf logic.
 [Nicholas, Andrew Dupont]

---
 CHANGELOG          | 2 ++
 src/dom.js         | 3 ++-
 test/unit/dom.html | 2 ++
 3 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/CHANGELOG b/CHANGELOG
index bac2d0c..ed2dc33 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,3 +1,5 @@
+* Fix a bug in the IE-specific Element#descendantOf logic. [Nicholas, Andrew Dupont]
+
 * Make Ajax.Updater clone its options hash before modifying it. Prevents memory leaks in Ajax.PeriodicalUpdater. Closes #10049 [Mislav Marohnić, Tobie Langel].
 
 * Remove useless variable in Selector.handlers.child. Closes #10006 [kuriyama]
diff --git a/src/dom.js b/src/dom.js
index 599c8ef..a46f841 100644
--- a/src/dom.js
+++ b/src/dom.js
@@ -359,6 +359,7 @@ Element.Methods = {
   
   descendantOf: function(element, ancestor) {
     element = $(element), ancestor = $(ancestor);
+    var originalAncestor = ancestor;
 
     if (element.compareDocumentPosition)
       return (element.compareDocumentPosition(ancestor) & 8) === 8;
@@ -374,7 +375,7 @@ Element.Methods = {
     }
     
     while (element = element.parentNode)
-      if (element == ancestor) return true;
+      if (element == originalAncestor) return true;
     return false;
   },
   
diff --git a/test/unit/dom.html b/test/unit/dom.html
index 59d7897..8f7dcc6 100644
--- a/test/unit/dom.html
+++ b/test/unit/dom.html
@@ -1031,6 +1031,8 @@
       assert(!$('sibling').descendantOf('child'), 'sibling < child');
       assert(!$('great-grand-child').descendantOf('not-in-the-family'), 'great-grand-child < not-in-the-family');
       assert(!$('child').descendantOf('not-in-the-family'), 'child < not-in-the-family');
+      
+      assert(!$(document.body).descendantOf('great-grand-child'));
     }},  
     
     testChildOf: function() {with(this) {