stdout and stderr not inherited when runtime: 'child_process'

[AriPerkkio]

Vitest's reporters go crazy when we cannot control how to print worker's process.stdout and process.stderr in main thread. These can be for example NodeJS deprecation warnings.

// main.mjs
import { URL } from 'node:url'
import Tinypool from 'tinypool'

const write = process.stdout.write.bind(process.stdout)

process.stdout.write = (data) => {
  write(`Captured stdout: ${data}\n`)
}

process.stderr.write = (data) => {
  write(`Captured stderr: ${data}\n`)
}

const pool = new Tinypool({
  runtime: 'child_process',
  filename: new URL('./worker.mjs', import.meta.url).href,
})

await pool.run()

// worker.mjs
export default function run() {
  process.stdout.write('Message')
  process.stderr.write('Error message')
}

$ node main.mjs 
Message
Error message

With runtime: 'worker_threads':

$ node main.mjs 
Captured stdout: Message

Captured stderr: Error message

• https://nodejs.org/api/child_process.html#optionsstdio
• https://nodejs.org/api/worker_threads.html