This function execute the another function and return the result or throw the error in the least given time, one of the use case is to protect agains timing-attack

run-for-at-least.ts

export async function runForAtLeast<T>(fn: (...args: any[]) => Promise<T>, ms?: number, ...args: any[]): Promise<T> {
  const [res] = await Promise.allSettled([
    fn(...args),
    new Promise(resolve => setTimeout(resolve, ms)),
  ]);
  switch (res.status) {
    case 'fulfilled':
      return res.value;
    case 'rejected':
      throw res.reason;
  }
}

usage.ts

runForAtLeast(async (username: string, password: string): Promise<string> => {
  // do login
  if (username === 'mosius' && password === '1234') {
    return 'token';
  }

  throw new Error('unauthorized');
  return 'token';
}, 1_000, 'mosius', '12345')
  .then(console.log)
  .catch(console.error);

Cool! I didn't know allSettled and 1_000 existed :)))