lib: speed up MessageEvent creation internally

PR-URL: nodejs#52951 Refs: nodejs/undici#3170 Reviewed-By: Benjamin Gruenbaum <[email protected]> Reviewed-By: Matteo Collina <[email protected]>
bmeck · Jun 22, 2024 · 0c507da · 0c507da
1 parent d06ab23
commit 0c507da
Showing 1 changed file with 8 additions and 5 deletions.
diff --git a/lib/internal/worker/io.js b/lib/internal/worker/io.js
@@ -85,9 +85,12 @@ const messageTypes = {
   LOAD_SCRIPT: 'loadScript',
 };
 
-let messageEvent;
-function lazyMessageEvent() {
-  return messageEvent ??= require('internal/deps/undici/undici').MessageEvent;
+// createFastMessageEvent skips webidl argument validation when the arguments
+// passed are known to be valid.
+let fastCreateMessageEvent;
+function lazyMessageEvent(type, init) {
+  fastCreateMessageEvent ??= require('internal/deps/undici/undici').createFastMessageEvent;
+  return fastCreateMessageEvent(type, init);
 }
 
 // We have to mess with the MessagePort prototype a bit, so that a) we can make
@@ -128,7 +131,7 @@ ObjectDefineProperty(
       }
       const ports = this[kCurrentlyReceivingPorts];
       this[kCurrentlyReceivingPorts] = undefined;
-      return new (lazyMessageEvent())(type, { data, ports });
+      return lazyMessageEvent(type, { data, ports });
     },
     configurable: false,
     writable: false,
@@ -321,7 +324,7 @@ function receiveMessageOnPort(port) {
 }
 
 function onMessageEvent(type, data) {
-  this.dispatchEvent(new (lazyMessageEvent())(type, { data }));
+  this.dispatchEvent(lazyMessageEvent(type, { data }));
 }
 
 function isBroadcastChannel(value) {