import { WorkerPool } from '../src/index.js';
import { waitFor } from './helpers.js';

describe('WorkerPool', () => {
  it('respects concurrency limits', async () => {
    const pool = new WorkerPool(2);
    let active = 0;
    let maxActive = 0;

    const tasks = Array.from({ length: 5 }, (_, index) =>
      pool.run(async () => {
        active += 1;
        maxActive = Math.max(maxActive, active);
        await new Promise((resolve) => {
          setTimeout(resolve, 20 + index);
        });
        active -= 1;
      }),
    );

    await Promise.all(tasks);
    await waitFor(() => pool.activeCount === 0 && pool.pendingCount === 0);

    expect(maxActive).toBe(2);
  });
});