esm: process proxy Symbol.toString fix

PR-URL: #25963
Reviewed-By: John-David Dalton <john.david.dalton@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Gus Caplan <me@gus.host>
Reviewed-By: Tiancheng "Timothy" Gu <timothygu99@gmail.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>

lib/internal/bootstrap/node.js

@@ -309,6 +309,12 @@ function setupProcessObject() {
   const origProcProto = Object.getPrototypeOf(process);
   Object.setPrototypeOf(origProcProto, EventEmitter.prototype);
   EventEmitter.call(process);
+  Object.defineProperty(process, Symbol.toStringTag, {
+    enumerable: false,
+    writable: false,
+    configurable: false,
+    value: 'process'
+  });
   // Make process globally available to users by putting it on the global proxy
   Object.defineProperty(global, 'process', {
     value: process,

test/es-module/test-esm-process.mjs

@@ -0,0 +1,6 @@
+// Flags: --experimental-modules
+import '../common';
+import assert from 'assert';
+import process from 'process';
+
+assert.strictEqual(Object.prototype.toString.call(process), '[object process]');