export default async function measure(fn, now = () => Date.now()) {
  throw new Error('Not implemented');
}

import measure from './measure';

describe('measure', () => {
  test('measures sync functions', async () => {
    let t = 0;
    const now = () => (t += 5);
    const { result, durationMs } = await measure(() => 42, now);
    expect(result).toBe(42);
    expect(durationMs).toBe(5);
  });

  test('measures async functions', async () => {
    let t = 100;
    const now = () => (t += 10);
    const { result, durationMs } = await measure(async () => 'ok', now);
    expect(result).toBe('ok');
    expect(durationMs).toBe(10);
  });

  test('propagates errors', async () => {
    const now = () => 1;
    await expect(measure(() => { throw new Error('boom'); }, now)).rejects.toThrow('boom');
  });


  test('propagates async rejections', async () => {
    const now = () => 1;
    await expect(measure(async () => { throw new Error('async boom'); }, now)).rejects.toThrow('async boom');
  });
});