lib: use kEmptyObject as default value for options

`kEmptyObject` is more suitable than {} if options don't
need mutation.

PR-URL: #46011
Reviewed-By: Antoine du Hamel <[email protected]>
Reviewed-By: Colin Ihrig <[email protected]>
Reviewed-By: Rafael Gonzaga <[email protected]>
Reviewed-By: Luigi Pinca <[email protected]>

Author: deokjinkim

lib/events.js

@@ -1002,8 +1002,9 @@ function eventTargetAgnosticAddListener(emitter, name, listener, flags) {
  * @param {{ signal: AbortSignal; }} [options]
  * @returns {AsyncIterator}
  */
-function on(emitter, event, options) {
-  const signal = options?.signal;
+function on(emitter, event, options = kEmptyObject) {
+  // Parameters validation
+  const signal = options.signal;
   validateAbortSignal(signal, 'options.signal');
   if (signal?.aborted)
     throw new AbortError(undefined, { cause: signal?.reason });

lib/internal/fs/watchers.js

@@ -14,7 +14,10 @@ const {
     ERR_INVALID_ARG_VALUE,
   },
 } = require('internal/errors');
-const { createDeferredPromise } = require('internal/util');
+const {
+  createDeferredPromise,
+  kEmptyObject,
+} = require('internal/util');
 
 const {
   kFsStatsFieldsNumber,
@@ -296,7 +299,7 @@ ObjectDefineProperty(FSEvent.prototype, 'owner', {
   set(v) { return this[owner_symbol] = v; }
 });
 
-async function* watch(filename, options = {}) {
+async function* watch(filename, options = kEmptyObject) {
   const path = toNamespacedPath(getValidatedPath(filename));
   validateObject(options, 'options');
 

lib/internal/http2/core.js

@@ -3326,7 +3326,7 @@ function createSecureServer(options, handler) {
 function createServer(options, handler) {
   if (typeof options === 'function') {
     handler = options;
-    options = {};
+    options = kEmptyObject;
   }
   return new Http2Server(options, handler);
 }

lib/internal/socketaddress.js

@@ -26,6 +26,7 @@ const {
 
 const {
   customInspectSymbol: kInspect,
+  kEmptyObject,
 } = require('internal/util');
 
 const { inspect } = require('internal/util/inspect');
@@ -44,7 +45,7 @@ class SocketAddress extends JSTransferable {
     return value?.[kHandle] !== undefined;
   }
 
-  constructor(options = {}) {
+  constructor(options = kEmptyObject) {
     super();
     validateObject(options, 'options');
     let { family = 'ipv4' } = options;

lib/net.js

@@ -108,6 +108,7 @@ const {
 } = require('internal/errors');
 const { isUint8Array } = require('internal/util/types');
 const { queueMicrotask } = require('internal/process/task_queues');
+const { kEmptyObject } = require('internal/util');
 const {
   validateAbortSignal,
   validateBoolean,
@@ -1584,7 +1585,7 @@ function Server(options, connectionListener) {
 
   if (typeof options === 'function') {
     connectionListener = options;
-    options = {};
+    options = kEmptyObject;
     this.on('connection', connectionListener);
   } else if (options == null || typeof options === 'object') {
     options = { ...options };