test runner does not pass cli flags to test files when running `--test`

[MoLow]

for example, running node --loader ts-node/esm --test a.test.ts will fail:

/// a.test.ts

import { test } from 'node:test'

test(async () => {
	const a: any = {};
});

the challenge is that each test file spawns a new process

[MoLow]

this is obviously the case for any other node flag

[aduh95]

A workaround is to use NODE_OPTIONS env variable (NODE_OPTIONS="--loader ts-node/esm" node --test a.test.ts). It would still be worth to find a better way to integrate loaders though.

[aduh95]

Related: #43973

[MoLow]

I am not sure what I did wrong on the first time I tested this, but I re-tested it and it does actually work.
see https://github.com/nodejs/node/blob/main/lib/internal/main/test_runner.js#L100-L102