<html>
<html>
<head>
<script src="../resources/testharness.js"></script>
<script src="../resources/testharnessreport.js"></script>
</head>
<body id="body">

    <div role="group" id="parent">
        <div role="button" id="button1">Button 1</div>
        <div role="button" id="button2">Button 2</div>
        <div role="button" id="button3">Button 3</div>
    </div>

<script>
function axElementById(id) {
    return accessibilityController.accessibleElementById(id);
}

test((t) => {
    // Get the parent element.
    var parent = axElementById("parent");

    // Get all three children.
    var button1 = axElementById("button1");
    var button2 = axElementById("button2");
    var button3 = axElementById("button3");

    // Verify that the 3 children are present.
    assert_equals(parent.childAtIndex(0).name, button1.name, "button1 is first");
    assert_equals(parent.childAtIndex(1).name, button2.name, "button2 is second");
    assert_equals(parent.childAtIndex(2).name, button3.name, "button3 is third");

    // Make the 2nd button hidden. Only 1 and 3 should be present.
    document.getElementById("button2").setAttribute("aria-hidden", "true");

    assert_equals(parent.childAtIndex(0).name, button1.name, "button1 is first after setting button2 aria-hidden");
    assert_equals(parent.childAtIndex(1).name, button3.name, "button3 is second after setting button2 aria-hidden");

    // Make the 1st button hidden. Only 3 should be present.
    document.getElementById("button1").setAttribute("aria-hidden", "true");

    assert_equals(parent.childAtIndex(0).name, button3.name, "button3 is first after setting button1 aria-hidden");

    // Make the 2nd button not hidden. 2 and 3 should be present.
    document.getElementById("button2").setAttribute("aria-hidden", "false");

    assert_equals(parent.childAtIndex(0).name, button2.name, "button2 is first after clearning button2 aria-hidden");
    assert_equals(parent.childAtIndex(1).name, button3.name, "button3 is second after clearing button2 aria-hidden");
}, "This test makes sure that when aria-hidden changes, the AX hierarchy is updated.");
</script>

</body>
</html>