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<html>
<head>
<title>Tests for passive event listeners</title>
<link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css">
<script src="/tests/SimpleTest/SimpleTest.js"></script>
<body>
<p id="display"></p>
<div id="dummy">
</div>
<script>
var listenerHitCount;
var doPreventDefault;
function listener(e)
{
listenerHitCount++;
if (doPreventDefault) {
// When this function is registered as a passive listener, this
// call should be a no-op and might report a console warning.
e.preventDefault();
}
}
function listener2(e)
{
if (doPreventDefault) {
e.preventDefault();
}
}
var elem = document.getElementById('dummy');
function doTest(description, passiveArg)
{
listenerHitCount = 0;
elem.addEventListener('test', listener, { passive: passiveArg });
// Test with a cancelable event
var e1 = new Event('test', { cancelable: true });
elem.dispatchEvent(e1);
is(listenerHitCount, 1, description + ' | hit count');
var expectedDefaultPrevented = (doPreventDefault && !passiveArg);
is(e1.defaultPrevented, expectedDefaultPrevented, description + ' | default prevented');
// Test with a non-cancelable event
var e2 = new Event('test', { cancelable: false });
elem.dispatchEvent(e2);
is(listenerHitCount, 2, description + ' | hit count after non-cancelable event');
is(e2.defaultPrevented, false, description + ' | default prevented on non-cancelable event');
// Test combining passive-enabled and "traditional" listeners
elem.addEventListener('test', listener2);
var e3 = new Event('test', { cancelable: true });
elem.dispatchEvent(e3);
is(listenerHitCount, 3, description + ' | hit count with second listener');
is(e3.defaultPrevented, doPreventDefault, description + ' | default prevented with second listener');
elem.removeEventListener('test', listener2);
elem.removeEventListener('test', listener);
}
function testAddListenerKey(passiveListenerFirst)
{
listenerHitCount = 0;
doPreventDefault = true;
elem.addEventListener('test', listener, { capture: false, passive: passiveListenerFirst });
// This second listener should not be registered, because the "key" of
// { type, callback, capture } is the same, even though the 'passive' flag
// is different.
elem.addEventListener('test', listener, { capture: false, passive: !passiveListenerFirst });
var e1 = new Event('test', { cancelable: true });
elem.dispatchEvent(e1);
is(listenerHitCount, 1, 'Duplicate addEventListener was correctly ignored');
is(e1.defaultPrevented, !passiveListenerFirst, 'Prevent-default result based on first registered listener');
// Even though passive is the opposite of the first addEventListener call, it
// should remove the listener registered above.
elem.removeEventListener('test', listener, { capture: false, passive: !passiveListenerFirst });
var e2 = new Event('test', { cancelable: true });
elem.dispatchEvent(e2);
is(listenerHitCount, 1, 'non-passive listener was correctly unregistered');
is(e2.defaultPrevented, false, 'no listener was registered to preventDefault this event');
}
function test()
{
doPreventDefault = false;
doTest('base case', undefined);
doTest('non-passive listener', false);
doTest('passive listener', true);
doPreventDefault = true;
doTest('base case', undefined);
doTest('non-passive listener', false);
doTest('passive listener', true);
testAddListenerKey(false);
testAddListenerKey(true);
}
test();
</script>
</body>
</html>
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