chromium/third_party/blink/web_tests/external/wpt/dom/nodes/Element-removeAttribute.html

<!DOCTYPE html>
<meta charset="utf-8">
<title>Element.prototype.removeAttribute</title>
<link rel=help href="https://dom.spec.whatwg.org/#dom-element-removeattribute">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>

<script>
"use strict";

test(() => {

  const el = document.createElement("p");
  el.setAttribute("x", "first");
  el.setAttributeNS("foo", "x", "second");

  assert_equals(el.attributes.length, 2);
  assert_equals(el.getAttribute("x"), "first");
  assert_equals(el.getAttributeNS(null, "x"), "first");
  assert_equals(el.getAttributeNS("foo", "x"), "second");

  // removeAttribute removes the first attribute with name "x" that
  // we set on the element, irrespective of namespace.
  el.removeAttribute("x");

  // The only attribute remaining should be the second one.
  assert_equals(el.getAttribute("x"), "second");
  assert_equals(el.getAttributeNS(null, "x"), null);
  assert_equals(el.getAttributeNS("foo", "x"), "second");
  assert_equals(el.attributes.length, 1, "one attribute");

}, "removeAttribute should remove the first attribute, irrespective of namespace, when the first attribute is " +
   "not in a namespace");

test(() => {

  const el = document.createElement("p");
  el.setAttributeNS("foo", "x", "first");
  el.setAttributeNS("foo2", "x", "second");

  assert_equals(el.attributes.length, 2);
  assert_equals(el.getAttribute("x"), "first");
  assert_equals(el.getAttributeNS("foo", "x"), "first");
  assert_equals(el.getAttributeNS("foo2", "x"), "second");

  // removeAttribute removes the first attribute with name "x" that
  // we set on the element, irrespective of namespace.
  el.removeAttribute("x");

  // The only attribute remaining should be the second one.
  assert_equals(el.getAttribute("x"), "second");
  assert_equals(el.getAttributeNS("foo", "x"), null);
  assert_equals(el.getAttributeNS("foo2", "x"), "second");
  assert_equals(el.attributes.length, 1, "one attribute");

}, "removeAttribute should remove the first attribute, irrespective of namespace, when the first attribute is " +
   "in a namespace");
</script>