chromium/third_party/blink/web_tests/external/wpt/html/dom/documents/dom-tree-accessors/document.forms.html

<!doctype html>
<meta charset=utf-8>
<title>Document.forms</title>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<div id=log></div>
<form id="form1">
<input type="button" name="thebutton" value="alpha">
<input type=radio name=r1 value=a>
<input type=radio name=r1 value=b>
<input type=radio name=r1 value=c>
<input type=radio name=r1 value=d>
<input type=radio name=r1 value=e>
</form>

<form id="form2">
<input type="button" name="thebutton" value="alpha">
<input type=radio name=r1 value="a">
<input type=radio name=r1 value="b">
<input type=radio name=r1 value="c">
<input type=radio name=r1 value="d">
<input type=radio name=r1 value="e">
</form>

<form id=""></form>
<script>
test(function() {
  assert_equals(document.forms.length, 3);
  assert_equals(document.forms[0].id, "form1");
  assert_equals(document.forms[1].id, "form2");
  assert_equals(document.forms.form1.id, "form1");
  assert_equals(document.forms.form2.id, "form2");
  assert_equals(document.forms.item(0).id, "form1");
  assert_equals(document.forms.item(1).id, "form2");
  assert_equals(document.forms.namedItem("form1").id, "form1");
  assert_equals(document.forms.namedItem("form2").id, "form2");
}, "document.forms")

test(function() {
  // The `item` method takes one *numeric* argument. Passing a string to `item`
  // results in that string getting converted to 0
  assert_equals(document.forms.item("form1").id, "form1");
  assert_equals(document.forms.item("form2").id, "form1");
}, "document.forms.item with string arg")

test(function() {
  assert_equals(document.forms[""], undefined);
  assert_equals(document.forms.namedItem(""), null);
}, "document.forms with empty string")

test(function() {
  var result = [];
  for (var p in document.forms) {
    result.push(p);
  }
  // https://webidl.spec.whatwg.org/#property-enumeration
  // If the object supports indexed properties, then the object’s supported
  // property indices are enumerated first, in numerical order.
  assert_array_equals(result.splice(0, 3), ["0", "1", "2"]);
  // [...]
  // Finally, any enumerable own properties or properties from the object’s
  // prototype chain are then enumerated, in no defined order.
  assert_array_equals(result.sort(), ["item", "namedItem", "length"].sort())
}, "document.forms iteration")

test(function() {
  var result = Object.getOwnPropertyNames(document.forms);
  assert_array_equals(result, ["0", "1", "2", "form1", "form2"])
}, "document.forms getOwnPropertyNames")

test(function() {
  var forms = document.forms;
  assert_true(forms instanceof HTMLCollection);
  assert_equals(forms.length, 3);

  var form = document.createElement("form");
  document.body.appendChild(form);
  assert_equals(forms.length, 4);

  document.body.removeChild(form);
  assert_equals(forms.length, 3);
}, "Document.forms should be a live collection");
</script>