| import { createNext } from 'e2e-utils' | |
| import { NextInstance } from 'e2e-utils' | |
| import { check } from 'next-test-utils' | |
| describe('useReportWebVitals hook', () => { | |
| let next: NextInstance | |
| beforeAll(async () => { | |
| next = await createNext({ | |
| files: __dirname, | |
| skipStart: true, | |
| env: {}, | |
| dependencies: { | |
| nanoid: '4.0.1', | |
| }, | |
| }) | |
| await next.start() | |
| }) | |
| afterAll(() => next.destroy()) | |
| // Analytics events are only sent in production | |
| it('should send web-vitals', async () => { | |
| await next.fetch('/report-web-vitals') | |
| let eventsCount = 0 | |
| const browser = await next.browser('/report-web-vitals', { | |
| beforePageLoad: (page) => { | |
| page.route('https://example.vercel.sh/vitals', (route) => { | |
| eventsCount += 1 | |
| route.fulfill() | |
| }) | |
| }, | |
| }) | |
| // Refresh will trigger CLS and LCP. When page loads FCP and TTFB will trigger: | |
| await browser.refresh() | |
| // After interaction LCP and FID will trigger | |
| await browser.elementById('btn').click() | |
| // Make sure all registered events in performance-relayer has fired | |
| await check(async () => { | |
| expect(eventsCount).toBeGreaterThanOrEqual(6) | |
| return 'success' | |
| }, 'success') | |
| }) | |
| }) | |