<!DOCTYPE html>
<html>
<body>
<script src="../../../resources/js-test.js"></script>
<script>

description('Test making the element data unique while replacing an Attr node.');

let element = document.createElement('div');
element.setAttribute('foo', 'bar');

let oldAttr = document.createAttributeNS('http://www.w3.org/XML/1998/namespace', 'width');
oldAttr.value = 'a';
element.setAttributeNode(oldAttr);

shouldBeEqualToString('element.getAttribute("width")', 'a');

element.addEventListener('DOMSubtreeModified', () => { element.cloneNode(); }, true);

let newAttr = document.createAttributeNS('http://www.w3.org/1999/xhtml','width');
newAttr.value = 'b';
element.setAttributeNode(newAttr);

shouldBeEqualToString('element.getAttribute("width")', 'b');

</script>		
</body>
</html>