From 2830ac2ac5fd3bde2cb0412a32361abbada9e6dc Mon Sep 17 00:00:00 2001
From: Tobie Langel <tobie.langel@gmail.com>
Date: Sun, 3 Feb 2008 22:29:29 +0000
Subject: [PATCH] prototype: Prevent Element#cumulativeOffset,
 Element#getOffsetParent, Element#positionedOffset, Element#viewportOffset and
 Element#clonePosition from throwing an error in IE when called on a
 parent-less element. Closes #9416, #10192, #10248.

---
 CHANGELOG          |  2 ++
 src/dom.js         | 13 +++++++++++++
 test/unit/dom.html | 18 ++++++++++++++++++
 3 files changed, 33 insertions(+)

diff --git a/CHANGELOG b/CHANGELOG
index 1415858..1b67198 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,3 +1,5 @@
+* Prevent Element#cumulativeOffset, Element#getOffsetParent, Element#positionedOffset, Element#viewportOffset and Element#clonePosition from throwing an error in IE when called on a parent-less element. Closes #9416, #10192, #10248. [ronstoney, psiborg, kangax]
+
 * Prevent Enumerable#eachSlice from entering into an endless loop if passed an argument smaller than 1. Closes #10665. [kangax, Tobie Langel]
 
 * Allow Selector to correctly detect the presence of namespaced attributes. Closes #10987. [Samuel Lebeau, Tobie Langel]
diff --git a/src/dom.js b/src/dom.js
index 6b44eed..d790b0e 100644
--- a/src/dom.js
+++ b/src/dom.js
@@ -717,6 +717,9 @@ else if (Prototype.Browser.IE) {
   Element.Methods.getOffsetParent = Element.Methods.getOffsetParent.wrap(
     function(proceed, element) {
       element = $(element);
+      // IE throws an error if element is not in document
+      try { element.offsetParent }
+      catch(e) { return $(document.body) }
       var position = element.getStyle('position');
       if (position !== 'static') return proceed(element);
       element.setStyle({ position: 'relative' });
@@ -730,6 +733,8 @@ else if (Prototype.Browser.IE) {
     Element.Methods[method] = Element.Methods[method].wrap(
       function(proceed, element) {
         element = $(element);
+        try { element.offsetParent }
+        catch(e) { return Element._returnOffset(0,0) }
         var position = element.getStyle('position');
         if (position !== 'static') return proceed(element);
         // Trigger hasLayout on the offset parent so that IE6 reports
@@ -744,6 +749,14 @@ else if (Prototype.Browser.IE) {
       }
     );
   });
+  
+  Element.Methods.cumulativeOffset = Element.Methods.cumulativeOffset.wrap(
+    function(proceed, element) {
+      try { element.offsetParent }
+      catch(e) { return Element._returnOffset(0,0) }
+      return proceed(element);
+    }
+  );
     
   Element.Methods.getStyle = function(element, style) {
     element = $(element);
diff --git a/test/unit/dom.html b/test/unit/dom.html
index c72face..0a7f629 100644
--- a/test/unit/dom.html
+++ b/test/unit/dom.html
@@ -1618,6 +1618,18 @@
       var afu = $('absolute_fixed_undefined');
       assertEnumEqual([afu.offsetLeft, afu.offsetTop],
         afu.positionedOffset());
+        
+      var element = new Element('div'), offset = element.positionedOffset();
+      assertEnumEqual([0,0], offset);
+      assertIdentical(0, offset.top);
+      assertIdentical(0, offset.left);
+    }},
+    
+    testCumulativeOffset: function() {with(this) {
+      var element = new Element('div'), offset = element.cumulativeOffset();
+      assertEnumEqual([0,0], offset);
+      assertIdentical(0, offset.top);
+      assertIdentical(0, offset.left);
     }},
     
     testViewportOffset: function() {with(this) {
@@ -1629,6 +1641,10 @@
         $('absolute_relative').viewportOffset());
       assertEnumEqual([20,30],
         $('absolute_relative_undefined').viewportOffset());
+      var element = new Element('div'), offset = element.viewportOffset();
+      assertEnumEqual([0,0], offset);
+      assertIdentical(0, offset.top);
+      assertIdentical(0, offset.left);
     }},
     
     testOffsetParent: function() {with(this) {
@@ -1636,6 +1652,8 @@
       assertEqual('body_absolute', $('absolute_relative').getOffsetParent().id);
       assertEqual('absolute_relative', $('inline').getOffsetParent().id);
       assertEqual('absolute_relative', $('absolute_relative_undefined').getOffsetParent().id);
+      
+      assertEqual(document.body, new Element('div').getOffsetParent());
     }},
 
     testAbsolutize: function() {with(this) {