135009 2014-07-16 22:50:14 -0700 assign undefined value to Element property throws TypeError 2014-07-17 18:31:12 -0700 1 1 1 Unclassified WebKit DOM 528+ (Nightly build) iPhone / iPad Other RESOLVED DUPLICATE 134841 P2 Major --- 1 huge.huang+webkitbug webkit-unassigned ap ggaren oliver zalan oldest_to_newest 1022962 0 huge.huang+webkitbug 2014-07-16 22:50:14 -0700 Prior to iOS8 Safari / Safari 8.0 if we assign undefined to Element property (like document.body.scrollTop) it fallback to 0 ```js document.body.scrollTop = undefined; TypeError: Type error column: 110 line: 1 message: "Type error" stack: "eval code↵eval@[native code]↵_evaluateOn↵_evaluateAndWrap↵evaluate" __proto__: Error ``` 1023144 1 oliver 2014-07-17 17:08:11 -0700 Hmmm, this is complaining about assigning NaN (undefined is being number coerced) Maybe due to fractional coordinates? 1023145 2 ap 2014-07-17 17:11:46 -0700 Good point. Can you still reproduce with a current WebKit nightly? I thought that the fractional coordinate change was already undone. 1023146 3 oliver 2014-07-17 17:13:06 -0700 I think this is a dupe of bug #134841 1023155 4 huge.huang+webkitbug 2014-07-17 18:05:27 -0700 awesome, I cannot repro in webkit nightly r171105 1023168 5 zalan 2014-07-17 18:31:12 -0700 (In reply to comment #2) > Good point. Can you still reproduce with a current WebKit nightly? I thought that the fractional coordinate change was already undone. It's been reverted only for Element.scroll*. Other properties' (Element.offset*, Element.client*) return type is still double. *** This bug has been marked as a duplicate of bug 134841 ***