events: improve Event compatibility

This fixes `Event` constructor to improve `Event Web API`
compatibility.

The test added was written by referring to
`wpt@dom/events/Event-constructors.any.js`.

Signed-off-by: Daeyeon Jeong daeyeon.dev@gmail.com

PR-URL: #43461
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Reviewed-By: LiviaMedeiros <livia@cirno.name>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

lib/internal/event_target.js

@@ -97,16 +97,15 @@ class Event {
  * composed?: boolean,
  * }} [options]
  */
- constructor(type, options = null) {
+ constructor(type, options = kEmptyObject) {
  if (arguments.length === 0)
  throw new ERR_MISSING_ARGS('type');
- validateObject(options, 'options', {
- allowArray: true, allowFunction: true, nullable: true,
- });
- const { cancelable, bubbles, composed } = { ...options };
+ validateObject(options, 'options');
+ const { bubbles, cancelable, composed } = options;
  this[kCancelable] = !!cancelable;
  this[kBubbles] = !!bubbles;
  this[kComposed] = !!composed;
+
  this[kType] = `${type}`;
  this[kDefaultPrevented] = false;
  this[kTimestamp] = now();

test/parallel/test-whatwg-events-event-constructors.js

@@ -0,0 +1,29 @@
+'use strict';
+
+require('../common');
+const { test, assert_equals, assert_array_equals } =
+ require('../common/wpt').harness;
+
+// Source: https://github.com/web-platform-tests/wpt/blob/6cef1d2087d6a07d7cc6cee8cf207eec92e27c5f/dom/events/Event-constructors.any.js#L91-L112
+test(function() {
+ const called = [];
+ const ev = new Event('Xx', {
+ get cancelable() {
+ called.push('cancelable');
+ return false;
+ },
+ get bubbles() {
+ called.push('bubbles');
+ return true;
+ },
+ get sweet() {
+ called.push('sweet');
+ return 'x';
+ },
+ });
+ assert_array_equals(called, ['bubbles', 'cancelable']);
+ assert_equals(ev.type, 'Xx');
+ assert_equals(ev.bubbles, true);
+ assert_equals(ev.cancelable, false);
+ assert_equals(ev.sweet, undefined);
+});