fix: use builtin node:process module over polyfill for Vitest pool (#5101)

Author: mrbbot

packages/vitest-pool-workers/src/mock-agent/index.cjs

@@ -1,4 +1,5 @@
 globalThis.global = globalThis;
+process.versions = { node: "18.0.0" };
 
 const MockAgent = require("undici/lib/mock/mock-agent");
 const { kClients } = require("undici/lib/core/symbols");

packages/vitest-pool-workers/src/pool/module-fallback.ts

@@ -39,11 +39,7 @@ function trimSuffix(suffix: string, value: string) {
 }
 
 // Node.js built-in modules provided by `workerd`
-const workerdBuiltinModules = VITEST_POOL_WORKERS_DEFINE_BUILTIN_MODULES.filter(
-	// `workerd`'s implementation of "node:process" doesn't support everything we
-	// need, so use our polyfill instead
-	(specifier) => specifier !== "node:process"
-);
+const workerdBuiltinModules = VITEST_POOL_WORKERS_DEFINE_BUILTIN_MODULES;
 const conditions = new Set(["workerd", "worker", "browser", "import"]);
 
 // `chai` contains circular `require()`s which aren't supported by `workerd`

packages/vitest-pool-workers/src/worker/index.ts

@@ -1,6 +1,7 @@
 import assert from "node:assert";
 import { Buffer } from "node:buffer";
 import events from "node:events";
+import process from "node:process";
 import * as vm from "node:vm";
 import {
 	importModule,
@@ -24,6 +25,11 @@ function structuredSerializableParse(value: string): unknown {
 }
 
 globalThis.Buffer = Buffer; // Required by `vite-node/source-map`
+
+globalThis.process = process; // Required by `vite-node`
+process.argv = []; // Required by `@vitest/utils`
+Object.setPrototypeOf(process, events.EventEmitter.prototype); // Required by `vitest`
+
 globalThis.__console = console;
 
 const originalSetTimeout = globalThis.setTimeout;