lib: use primordials for navigator.userAgent

PR-URL: #50467 Reviewed-By: Geoffrey Booth <[email protected]> Reviewed-By: Vinícius Lourenço Claro Cardoso <[email protected]> Reviewed-By: Yagiz Nizipli <[email protected]> Reviewed-By: James M Snell <[email protected]> Reviewed-By: Tobias Nießen <[email protected]> Reviewed-By: Ethan Arrowood <[email protected]>

Author: Uzlopak

lib/internal/navigator.js

@@ -0,0 +1,61 @@
+'use strict';
+
+const{
+ ObjectDefineProperties,
+ StringPrototypeIndexOf,
+ StringPrototypeSlice,
+ Symbol,
+}=primordials;
+
+const{
+ERR_ILLEGAL_CONSTRUCTOR,
+}=require('internal/errors').codes;
+
+const{
+ kEnumerableProperty,
+}=require('internal/util');
+
+const{
+ getAvailableParallelism,
+}=internalBinding('os');
+
+constkInitialize=Symbol('kInitialize');
+constnodeVersion=process.version;
+
+classNavigator{
+// Private properties are used to avoid brand validations.
+ #availableParallelism;
+ #userAgent =`Node.js/${StringPrototypeSlice(nodeVersion,1,StringPrototypeIndexOf(nodeVersion,'.'))}`;
+
+constructor(){
+if(arguments[0]===kInitialize){
+return;
+}
+thrownewERR_ILLEGAL_CONSTRUCTOR();
+}
+
+/**
+ * @return{number}
+ */
+gethardwareConcurrency(){
+this.#availableParallelism ??=getAvailableParallelism();
+returnthis.#availableParallelism;
+}
+
+/**
+ * @return{string}
+ */
+getuserAgent(){
+returnthis.#userAgent;
+}
+}
+
+ObjectDefineProperties(Navigator.prototype,{
+hardwareConcurrency: kEnumerableProperty,
+userAgent: kEnumerableProperty,
+});
+
+module.exports={
+navigator: newNavigator(kInitialize),
+ Navigator,
+};