<!DOCTYPE html> <title> postMessage(): MessageEvent properties </title> <script src="/resources/testharness.js"></script> <script src="/resources/testharnessreport.js"></script> <div id=log></div> <script> async_test(function(t) { var channel = new MessageChannel(); var targetPort = channel.port2; targetPort.start(); targetPort.addEventListener("message", t.step_func_done(function (evt) { assert_class_string(evt, "MessageEvent"); assert_equals(evt.type, "message"); assert_false(evt.bubbles, "bubbles should be false"); assert_false(evt.cancelable, "cancelable should be false"); assert_equals(evt.data, "ping", "data"); assert_equals(evt.origin, "", "origin"); assert_equals(evt.lastEventId, "", "lastEventId"); assert_equals(evt.source, null, "source"); assert_array_equals(evt.ports, [], "ports"); }), true); channel.port1.postMessage("ping"); }); </script>