I have a function that uses the exported method execFile from child_process package. I want to test my function. In order to test it, I need to stub the execFile, so it will return only after 5 seconds.

Something like this:

const statStub = sinon.stub(child_process, 'execFile').callsFake((
  file: string,
  args: ReadonlyArray<string> | undefined | null,
  options: ({ encoding?: string | null } & ExecFileOptions) | undefined | null,
  callback: ((error: ExecException | null, stdout: string | Buffer, stderr: string | Buffer) => void) | undefined | null,
) => {
  sleepSomehow(5);

  return execFile(file, args, options, callback);
})

I am not sure that's the correct way, and furthermore I can't really implement this sleepSomehow function. So how do I stub execFile to just stall 5 seconds?