src/third_party/web_platform_tests/dom/events/Event-propagation.html

<!doctype html>
<title>Event propagation tests</title>
<link rel=author title="Aryeh Gregor" href=ayg@aryeh.name>
<div id=log></div>
<script src=/resources/testharness.js></script>
<script src=/resources/testharnessreport.js></script>
<script>
"use strict";

function testPropagationFlag(ev, expected, desc) {
  test(function() {
    var called = false;
    var callback = function() { called = true };
    document.head.addEventListener("foo", callback);
    document.head.dispatchEvent(ev);
    // Gecko resets the flags after dispatching; it will happily dispatch
    // the event the second time around.
    document.head.dispatchEvent(ev);
    assert_equals(called, expected, "Propagation flag");
    document.head.removeEventListener("foo", callback);
  }, desc);
}

var ev = document.createEvent("Event");
ev.initEvent("foo", true, false);
testPropagationFlag(ev, true, "Newly-created Event");
ev.stopPropagation();
testPropagationFlag(ev, false, "After stopPropagation()");
ev.initEvent("foo", true, false);
testPropagationFlag(ev, true, "Reinitialized after stopPropagation()");

var ev = document.createEvent("Event");
ev.initEvent("foo", true, false);
ev.stopImmediatePropagation();
testPropagationFlag(ev, false, "After stopImmediatePropagation()");
ev.initEvent("foo", true, false);
testPropagationFlag(ev, true, "Reinitialized after stopImmediatePropagation()");
</script>