Test TreeWalker with skipping On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE". Testing nextSibling PASS walker.firstChild(); walker.currentNode.id is 'B1' PASS walker.nextSibling(); walker.currentNode.id is 'B3' Testing previousSibling PASS walker.previousSibling(); walker.currentNode.id is 'B1' PASS successfullyParsed is true TEST COMPLETE