Bug 98025 – [Microdata] itemprop names must not override builtin properties

• Status: RESOLVED
• Resolution: FIXED
• Component: DOM

[Arko Saha]

HTMLPropertiesCollection[propertyName] must not return PropertyNodeList if 'propertyName' is a method of HTMLPropertiesCollection interface.

Sample test:

test(function () {
	var testEl = makeEl('div',{itemscope:'itemscope', id:'outerDiv'});
	var item = testEl.properties.item;
	testEl.innerHTML = '<div itemprop="item" id="innerDiv"></div>';
	assert_equals( testEl.properties['item'], item, 'item' );
}, 'itemprop names must not override builtin properties');

Expected: testEl.properties['item'] should not return PropertyNodeList (NodeList contains innerDiv) because 'item' is a method of HTMLPropertiesCollection interface.

It should return -

function item() {
    [native code]
}

Actual: Returns "[object PropertyNodeList]"

[Arko Saha]

Created attachment 166464 [details]
Patch

[Kentaro Hara]

Comment on attachment 166464 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=166464&action=review

Looks good.

> Source/WebCore/ChangeLog:10
> +        We should look in the prototype for functions before assuming it as
> +        an item's name. Return false if the prototype of the object has a
> +        property (function) with propertyName.

Would you add a spec link to the ChangeLog? (I'm sure this change would be correct, but I'd like to verify it in the spec just in case.)

[Arko Saha]

(In reply to comment #2)
> Would you add a spec link to the ChangeLog? (I'm sure this change would be correct, but I'd like to verify it in the spec just in case.)

Named properties spec is defined http://dev.w3.org/2006/webapi/WebIDL/#idl-named-properties
According to named property visibility algorithm http://dev.w3.org/2006/webapi/WebIDL/#indexed-and-named-properties
...
7. If the result of calling the [[HasProperty]] internal method on prototype with property name P is true, then return false.
...

Also [OverrideBuiltins] is not declared for any of the properties, hence no overriding is allowed in this case.

[Kentaro Hara]

Comment on attachment 166464 [details]
Patch

Thanks for the clarification!

[Arko Saha]

Committed r130255: <http://trac.webkit.org/changeset/130255>