chromium/content/test/data/accessibility/event/aria-haspopup-changed.html

<!DOCTYPE html>
<html>
<body>
  <input id="input0" aria-label="input0" role="combobox">
  <input id="input1" aria-label="input1" role="combobox">
  <input id="input2" aria-label="input2" role="combobox">
  <input id="input3" aria-label="input3" role="combobox">
  <input id="input4" aria-label="input4" role="combobox">
  <input id="input5" aria-label="input5" role="combobox">
  <input id="input6" aria-label="input6" role="combobox">
  <input id="input7" aria-label="input7" role="combobox" aria-haspopup="true">
  <script>
    function go() {
      // Set aria-haspopup from combobox default(listbox)->listbox;
      // should not fire an event.
      document.getElementById('input0').setAttribute('aria-haspopup', 'listbox');

      // Set aria-haspopup from combobox default(listbox, false)->false;
      // should fire an event.
      document.getElementById('input1').setAttribute('aria-haspopup', 'false');

      // Set aria-haspopup from combobox default(listbox)->true(menu);
      // should fire an event.
      document.getElementById('input2').setAttribute('aria-haspopup', 'true');

      // Set aria-haspopup from combobox default(listbox)->menu;
      // should fire an event.
      document.getElementById('input3').setAttribute('aria-haspopup', 'menu');

      // Set aria-haspopup from combobox default(listbox)->tree;
      // should fire an event.
      document.getElementById('input4').setAttribute('aria-haspopup', 'tree');

      // Set aria-haspopup from combobox default(listbox)->grid;
      // should fire an event.
      document.getElementById('input5').setAttribute('aria-haspopup', 'grid');

      // Set aria-haspopup from combobox default(listbox)->dialog;
      // should fire an event.
      document.getElementById('input6').setAttribute('aria-haspopup', 'dialog');

      // Remove aria-haspopup. Set aria-haspopup from true(menu)->default(listbox);
      // should fire an event.
      document.getElementById('input7').removeAttribute('aria-haspopup');
    }
  </script>
</body>
</html>