import { describe, it, expect, vi, beforeEach, afterEach } from 'vitest';
import { RateLimiter, ExponentialBackoff } from '../../src/utils/rate-limiter.js';
describe('RateLimiter', () => {
beforeEach(() => {
vi.useFakeTimers();
});
afterEach(() => {
vi.useRealTimers();
});
it('should not throttle first request', async () => {
const limiter = new RateLimiter(1000);
const start = Date.now();
const throttlePromise = limiter.throttle();
await vi.runAllTimersAsync();
await throttlePromise;
const elapsed = Date.now() - start;
expect(elapsed).toBeLessThan(100); // Should be nearly instant
});
it('should throttle subsequent requests', async () => {
const limiter = new RateLimiter(1000);
// First request
await limiter.throttle();
vi.advanceTimersByTime(0);
// Second request should wait
const start = Date.now();
const throttlePromise = limiter.throttle();
// Advance time by 1000ms
vi.advanceTimersByTime(1000);
await throttlePromise;
const elapsed = Date.now() - start;
expect(elapsed).toBeGreaterThanOrEqual(1000);
});
it('should not throttle if enough time has passed', async () => {
const limiter = new RateLimiter(1000);
// First request
await limiter.throttle();
// Wait 2 seconds
vi.advanceTimersByTime(2000);
// Second request should not wait
const start = Date.now();
const throttlePromise = limiter.throttle();
await vi.runAllTimersAsync();
await throttlePromise;
const elapsed = Date.now() - start;
expect(elapsed).toBeLessThan(100);
});
});
describe('ExponentialBackoff', () => {
it('should return increasing delays', () => {
const backoff = new ExponentialBackoff({ baseMs: 1000, factor: 2, maxMs: 60000 });
expect(backoff.getNextDelay()).toBe(1000); // 1000 * 2^0
expect(backoff.getNextDelay()).toBe(2000); // 1000 * 2^1
expect(backoff.getNextDelay()).toBe(4000); // 1000 * 2^2
expect(backoff.getNextDelay()).toBe(8000); // 1000 * 2^3
});
it('should cap at maxMs', () => {
const backoff = new ExponentialBackoff({ baseMs: 10000, factor: 2, maxMs: 30000 });
expect(backoff.getNextDelay()).toBe(10000);
expect(backoff.getNextDelay()).toBe(20000);
expect(backoff.getNextDelay()).toBe(30000); // Capped
expect(backoff.getNextDelay()).toBe(30000); // Still capped
});
it('should reset attempt counter', () => {
const backoff = new ExponentialBackoff({ baseMs: 1000, factor: 2, maxMs: 60000 });
backoff.getNextDelay(); // 1000
backoff.getNextDelay(); // 2000
backoff.getNextDelay(); // 4000
backoff.reset();
expect(backoff.getNextDelay()).toBe(1000); // Back to base
});
it('should use default values', () => {
const backoff = new ExponentialBackoff();
expect(backoff.getNextDelay()).toBe(2000); // Default base
});
});
