events: add off alias to removeListener

Add `off` as an alias for `removeListener`

PR-URL: #17156
Refs: #17102
Reviewed-By: Anatoli Papirovski <[email protected]>
Reviewed-By: Benjamin Gruenbaum <[email protected]>
Reviewed-By: Matteo Collina <[email protected]>
Reviewed-By: Franziska Hinkelmann <[email protected]>
Reviewed-By: Fedor Indutny <[email protected]>
Reviewed-By: James M Snell <[email protected]>
Reviewed-By: Jan Krems <[email protected]>
Reviewed-By: Evan Lucas <[email protected]>
Reviewed-By: Sakthipriyan Vairamani <[email protected]>
Reviewed-By: Benedikt Meurer <[email protected]>
Reviewed-By: Anna Henningsen <[email protected]>
Reviewed-By: Timothy Gu <[email protected]>
Reviewed-By: Michaël Zasso <[email protected]>
Reviewed-By: Khaidi Chu <[email protected]>
Reviewed-By: Yuta Hiroto <[email protected]>
Reviewed-By: Gireesh Punathil <[email protected]>
Reviewed-By: Ruben Bridgewater <[email protected]>

lib/events.js

@@ -307,6 +307,8 @@ EventEmitter.prototype.removeListener =
       return this;
     };
 
+EventEmitter.prototype.off = EventEmitter.prototype.removeListener;
+
 EventEmitter.prototype.removeAllListeners =
     function removeAllListeners(type) {
       var listeners, events, i;

test/parallel/test-event-emitter-method-names.js

@@ -27,8 +27,9 @@ const events = require('events');
 const E = events.EventEmitter.prototype;
 assert.strictEqual(E.constructor.name, 'EventEmitter');
 assert.strictEqual(E.on, E.addListener);  // Same method.
+assert.strictEqual(E.off, E.removeListener);  // Same method.
 Object.getOwnPropertyNames(E).forEach(function(name) {
-  if (name === 'constructor' || name === 'on') return;
+  if (name === 'constructor' || name === 'on' || name === 'off') return;
   if (typeof E[name] !== 'function') return;
   assert.strictEqual(E[name].name, name);
 });