shadow-dom/input-element-list.html

<!doctype html>
<meta charset=utf-8>
<title>Input.list</title>
<script src=/resources/testharness.js></script>
<script src=/resources/testharnessreport.js></script>
<div id="testcontent">
  <input id="input" list="datalist">
</div>
<script>

test(() => {
  assert_equals(document.getElementById('input').list, null);
  var dl = document.createElement("datalist");
  dl.id = "datalist";
  document.getElementById("testcontent").appendChild(dl);
  assert_equals(document.getElementById('input').list, dl);
}, "Input element's list attribute should point to the datalist element.");


test(() => {
  var host = document.createElement("div");
  document.getElementById("testcontent").appendChild(host);
  var sr = host.attachShadow({mode: "open"});
  var input = document.createElement("input");
  input.setAttribute("list", "datalist");
  sr.appendChild(input);
  assert_equals(input.list, null);

  var dl = document.createElement("datalist");
  dl.id = "datalist";
  sr.appendChild(dl);
  assert_equals(input.list, dl);

  dl.remove();
  assert_equals(input.list, null);
}, "Input element's list attribute should point to the datalist element in Shadow DOM.");


</script>