firefox/toolkit/content/tests/chrome/test_popup_keys.xhtml

<?xml version="1.0"?>
<?xml-stylesheet href="chrome://global/skin" type="text/css"?>
<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css" type="text/css"?>

<window title="Menu ignorekeys Test"
        onkeydown="keyDown()" onkeypress="gKeyPressCount++; event.stopPropagation(); event.preventDefault();"
        onload="runTests();"
        xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">

  <script src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"></script>      
  <script src="chrome://mochikit/content/tests/SimpleTest/EventUtils.js"></script>      

<!--
  This test checks that the ignorekeys attribute can be used on a menu to
  disable key navigation. The test is performed twice by opening the menu,
  simulating a cursor down key, and closing the popup. When keys are enabled,
  the first item on the menu should be highlighted, otherwise the first item
  should not be highlighted.
  -->

<menupopup id="popup">
  <menuitem id="i1" label="One"/>
  <menuitem id="i2" label="Two"/>
  <menuitem id="i3" label="Three"/>
  <menuitem id="i4" label="Four"/>
</menupopup>

<script class="testbody" type="application/javascript">
<![CDATA[

SimpleTest.waitForExplicitFinish();

let gIgnoreKeys = false;
let gKeyPressCount = 0;
let gLastFirstMenuActiveValue = null;


function waitForEvent(target, eventName) {
  return new Promise(resolve => {
    target.addEventListener(eventName, function eventOccurred() {
      resolve();
    }, { once: true});
  });
}

function runTests()
{
  function promiseFlushingMutationObserver() {
    return new Promise(SimpleTest.executeSoon);
  }

  (async function() {
    const observer = new MutationObserver(checkIfFirstMenuItemActive);
    observer.observe($("i1"), { attributes: true });

    var popup = $("popup");
    is(popup.hasAttribute("ignorekeys"), false, "keys enabled");

    let popupShownPromise = waitForEvent(popup, "popupshown");
    popup.openPopup(null, "after_start");
    await popupShownPromise;

    let popupHiddenPromise = waitForEvent(popup, "popuphidden");
    info("Synthesizing ArrowDown (no ignorekeys)...");
    synthesizeKey("KEY_ArrowDown");
    await popupHiddenPromise;

    is(gKeyPressCount, 0, "keypresses with ignorekeys='false'");

    gIgnoreKeys = true;
    popup.setAttribute("ignorekeys", "true");
    // clear this first to avoid confusion
    observer.disconnect();
    $("i1").removeAttribute("_moz-menuactive")
    await promiseFlushingMutationObserver();
    observer.observe($("i1"), { attributes: true });

    popupShownPromise = waitForEvent(popup, "popupshown");
    popup.openPopup(null, "after_start");
    await popupShownPromise;

    info("Synthesizing ArrowDown (ignorekeys=\"true\")...");
    synthesizeKey("KEY_ArrowDown");

    await new Promise(resolve => setTimeout(() => resolve(), 1000));
    popupHiddenPromise = waitForEvent(popup, "popuphidden");
    popup.hidePopup();
    await popupHiddenPromise;

    is(gKeyPressCount, 1, "keypresses with ignorekeys='true'");

    popup.setAttribute("ignorekeys", "shortcuts");
    // clear this first to avoid confusion
    observer.disconnect();
    $("i1").removeAttribute("_moz-menuactive")
    await promiseFlushingMutationObserver();
    observer.observe($("i1"), { attributes: true });

    popupShownPromise = waitForEvent(popup, "popupshown");
    popup.openPopup(null, "after_start");
    await popupShownPromise;

    // When ignorekeys="shortcuts", T should be handled but accel+T should propagate.
    info("Synthesizing \"t\"...");
    sendString("t");
    is(gKeyPressCount, 1, "keypresses after t pressed with ignorekeys='shortcuts'");

    info("Synthesizing Accel-T...");
    synthesizeKey("t", { accelKey: true });
    is(gKeyPressCount, 2, "keypresses after accel+t pressed with ignorekeys='shortcuts'");

    popupHiddenPromise = waitForEvent(popup, "popuphidden");
    popup.hidePopup();
    await popupHiddenPromise;

    observer.disconnect();
    SimpleTest.finish();
  })();
}

function checkIfFirstMenuItemActive(aMutationList) {
  for (const mutation of aMutationList) {
    if (mutation.type != "attributes" || mutation.attributeName != "_moz-menuactive") {
      continue;
    }

    // the attribute should not be changed when ignorekeys is enabled
    if (gIgnoreKeys) {
      ok(false, "move key with keys disabled");
      return;
    }

    is(
      $("popup").hasAttribute("ignorekeys")
        ? gLastFirstMenuActiveValue
        : $("i1").getAttribute("_moz-menuactive"),
      "true",
      "move key with keys enabled"
    );
    $("popup").hidePopup();
    gLastFirstMenuActiveValue = null;
    break;
  }
}

function keyDown() {
  // when keys are enabled, the menu should have stopped propagation of the
  // event, so a bubbling listener for a keydown event should only occur
  // when keys are disabled.
  ok(gIgnoreKeys, "key listener fired with keys " +
                  (gIgnoreKeys ? "disabled" : "enabled"));
  gLastFirstMenuActiveValue = $("i1").getAttribute("_moz-menuactive");
}

]]>
</script>

<body xmlns="http://www.w3.org/1999/xhtml">
<p id="display">
</p>
<div id="content" style="display: none">
</div>
<pre id="test">
</pre>
</body>

</window>