events: initial implementation of experimental EventTarget

See documentation changes for details

Signed-off-by: James M Snell <jasnell@gmail.com>

PR-URL: https://github.com/nodejs/node/pull/33556
Refs: https://github.com/nodejs/node/pull/33527
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Bradley Farias <bradley.meck@gmail.com>

1 files changed, 24 insertions, 0 deletions

diff --git a/benchmark/events/eventtarget.js b/benchmark/events/eventtarget.js
new file mode 100644
index 0000000000..7a7253aefb
--- /dev/null
+++ b/benchmark/events/eventtarget.js
@@ -0,0 +1,24 @@
+'use strict';
+const common = require('../common.js');
+
+const bench = common.createBenchmark(main, {
+  n: [2e7],
+  listeners: [1, 5, 10]
+}, { flags: ['--expose-internals'] });
+
+function main({ n, listeners }) {
+  const { EventTarget, Event } = require('internal/event_target');
+  const target = new EventTarget();
+
+  for (let n = 0; n < listeners; n++)
+    target.addEventListener('foo', () => {});
+
+  const event = new Event('foo');
+
+  bench.start();
+  for (let i = 0; i < n; i++) {
+    target.dispatchEvent(event);
+  }
+  bench.end(n);
+
+}