`node:worker_threads` does not load `--import file.js` unless explicitly setting `env` option

[AriPerkkio]

Version

v22.22.0

Platform

Darwin Aris-MacBook-Air.local 25.3.0 Darwin Kernel Version 25.3.0: Wed Jan 28 20:56:34 PST 2026; root:xnu-12377.91.3~2/RELEASE_ARM64_T8112 arm64

Subsystem

No response

What steps will reproduce the bug?

Create file worker-repro.mjswith following:

import { writeFileSync } from "node:fs";
import { Worker, isMainThread } from "node:worker_threads";

if (isMainThread) {
  process.env.NODE_OPTIONS ||= "";
  process.env.NODE_OPTIONS += " --import ./worker-loader.mjs";
  process.env.HELLO_WORLD = "Hello, World!";

  writeFileSync(
    "./worker-loader.mjs",
    `console.log("[loader]", { pid: process.pid });`,
  );

  console.log("[main]", { pid: process.pid });
  new Worker("./worker-repro.mjs");
}

if (!isMainThread) {
  console.log("[worker]", {
    pid: process.pid,
    NODE_OPTIONS: process.env.NODE_OPTIONS,
    HELLO_WORLD: process.env.HELLO_WORLD,
  });
}

How often does it reproduce? Is there a required condition?

Always

What is the expected behavior? Why is that the expected behavior?

$ node worker-repro.mjs 
[main] { pid: 44824 }
[loader] { pid: 44824 }
[worker] {
  pid: 44824,
  NODE_OPTIONS: ' --import ./worker-loader.mjs',
  HELLO_WORLD: 'Hello, World!'
}

I expect [loader] { pid: 44824 } to be logged. The file passed via --import should be loaded before [worker] context is loaded.

With following change the loader is loaded as expected:

- new Worker("./worker-repro.mjs");
+ new Worker("./worker-repro.mjs", { env: process.env });

But this change should not be needed. Even without this change we can see that [worker] is logging same NODE_OPTIONS and HELLO_WORLD environment variables that parent set.

What do you see instead?

--import has no effect, there is no [loader] { pid: 44824 } logged.

$ node worker-repro.mjs 
[main] { pid: 44790 }
[worker] {
  pid: 44790,
  NODE_OPTIONS: ' --import ./worker-loader.mjs',
  HELLO_WORLD: 'Hello, World!'
}

Additional information

No response

[semimikoh]

I've opened a PR to fix this: #62306

The issue is in src/node_worker.cc. When env option is not provided, args[1] is null, and the NODE_OPTIONS parsing block is gated behind args[1]->IsObject() || args[2]->IsArray(), which skips parsing entirely. Adding args[1]->IsNull() to the condition fixes it.