events: return values directly in listeners

apapirovski · addaleax · commit 11b23c8a9125 · 2017-12-07T17:29:54.000+01:00
Each conditional branch in EventEmitter.prototype.listeners assigns its return value to a variable ret which is returned at the end. Instead just return from within each branch. This is both clearer and more performant. events/ee-listeners.js n=5000000 3.65 % *** 3.359171e-10 PR-URL: nodejs/node#16212 Reviewed-By: Luigi Pinca <luigipinca@gmail.com> Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de> Reviewed-By: James M Snell <jasnell@gmail.com> Reviewed-By: Refael Ackermann <refack@gmail.com>
diff --git a/lib/extras/events.js b/lib/extras/events.js
@@ -484,23 +484,19 @@ EventEmitter.prototype.removeAllListeners =
     };
 
 EventEmitter.prototype.listeners = function listeners(type) {
-  var evlistener;
-  var ret;
-  var events = this._events;
+  const events = this._events;
 
   if (events === undefined)
-    ret = [];
-  else {
-    evlistener = events[type];
-    if (evlistener === undefined)
-      ret = [];
-    else if (typeof evlistener === 'function')
-      ret = [evlistener.listener || evlistener];
-    else
-      ret = unwrapListeners(evlistener);
-  }
+    return [];
 
-  return ret;
+  const evlistener = events[type];
+  if (evlistener === undefined)
+    return [];
+
+  if (typeof evlistener === 'function')
+    return [evlistener.listener || evlistener];
+
+  return unwrapListeners(evlistener);
 };
 
 EventEmitter.listenerCount = function(emitter, type) {
