<!DOCTYPE HTML> <meta charset=utf-8> <title>Null test</title> <script src="/resources/testharness.js"></script> <script src="/resources/testharnessreport.js"></script> <h1>Test of previousElementSibling and nextElementSibling returning null</h1> <div id="log"></div> <p id="parentEl">The result of this test is <span id="first_element_child" style="font-weight:bold;">unknown.</span></p> <script> test(function() { var fec = document.getElementById("first_element_child"); assert_equals(fec.previousElementSibling, null) assert_equals(fec.nextElementSibling, null) }) </script>