jest-worker: Unable to customize thread execArgv with enableThreadWorkers

packages/jest-worker/src/types.ts

@@ -125,6 +125,7 @@ export type WorkerOptions = {
   setupArgs: Array<unknown>;
   maxRetries: number;
   workerId: number;
+  workerData?: unknown;
   workerPath: string;
 };
 

packages/jest-worker/src/workers/NodeThreadsWorker.ts

@@ -7,10 +7,7 @@
 
 import * as path from 'path';
 import {PassThrough} from 'stream';
-import {
-  Worker,
-  WorkerOptions as WorkerThreadsWorkerOptions,
-} from 'worker_threads';
+import {Worker} from 'worker_threads';
 import mergeStream = require('merge-stream');
 import {
   CHILD_MESSAGE_INITIALIZE,
@@ -63,22 +60,19 @@ export default class ExperimentalWorker implements WorkerInterface {
 
   initialize(): void {
     this._worker = new Worker(path.resolve(__dirname, './threadChild.js'), {
+      env: {
+        ...process.env,
+        JEST_WORKER_ID: String(this._options.workerId + 1), // 0-indexed workerId, 1-indexed JEST_WORKER_ID
+      },
       eval: false,
+      execArgv: process.execArgv,
+      // @ts-expect-error: added in newer versions
       resourceLimits: this._options.resourceLimits,
       stderr: true,
       stdout: true,
-      workerData: {
-        cwd: process.cwd(),
-        env: {
-          ...process.env,
-          JEST_WORKER_ID: String(this._options.workerId + 1), // 0-indexed workerId, 1-indexed JEST_WORKER_ID
-        } as NodeJS.ProcessEnv,
-        // Suppress --debug / --inspect flags while preserving others (like --harmony).
-        execArgv: process.execArgv.filter(v => !/^--(debug|inspect)/.test(v)),
-        silent: true,
-        ...this._options.forkOptions,
-      },
-    } as WorkerThreadsWorkerOptions);
+      workerData: this._options.workerData,
+      ...this._options.forkOptions,
+    });
 
     if (this._worker.stdout) {
       if (!this._stdout) {

packages/jest-worker/src/workers/__tests__/NodeThreadsWorker.test.js

@@ -51,33 +51,36 @@ afterEach(() => {
   process.execArgv = originalExecArgv;
 });
 
-it('passes fork options down to child_process.fork, adding the defaults', () => {
+it('passes fork options down to worker_threads.Worker, adding the defaults', () => {
   const thread = require.resolve('../threadChild');
 
   process.execArgv = ['--inspect', '-p'];
 
   // eslint-disable-next-line no-new
   new Worker({
     forkOptions: {
-      cwd: '/tmp',
       execPath: 'hello',
     },
     maxRetries: 3,
+    workerData: {
+      foo: 'bar',
+    },
     workerId: process.env.JEST_WORKER_ID - 1,
     workerPath: '/tmp/foo/bar/baz.js',
   });
 
   expect(workerThreads.mock.calls[0][0]).toBe(thread.replace(/\.ts$/, '.js'));
   expect(workerThreads.mock.calls[0][1]).toEqual({
+    env: process.env, // Default option.
     eval: false,
+    execArgv: ['--inspect', '-p'],
+    execPath: 'hello', // Added option.
+    resourceLimits: undefined,
     stderr: true,
     stdout: true,
     workerData: {
-      cwd: '/tmp', // Overridden default option.
-      env: process.env, // Default option.
-      execArgv: ['-p'], // Filtered option.
-      execPath: 'hello', // Added option.
-      silent: true, // Default option.
+      // Added option.
+      foo: 'bar',
     },
   });
 });
@@ -91,9 +94,7 @@ it('passes workerId to the thread and assign it to env.JEST_WORKER_ID', () => {
     workerPath: '/tmp/foo',
   });
 
-  expect(workerThreads.mock.calls[0][1].workerData.env.JEST_WORKER_ID).toEqual(
-    '3',
-  );
+  expect(workerThreads.mock.calls[0][1].env.JEST_WORKER_ID).toEqual('3');
 });
 
 it('initializes the thread with the given workerPath', () => {