Browser Test Loop

Code that compiles is not code that works. This is the loop that closes the gap between "the diff looks right" and "the page does the thing".

Core Behavior

Drive a real browser against the running app, assert on what actually rendered, and fix what fails. Never report a UI change as working on the strength of the diff alone.

Setup

Playwright is the default. It installs its own browsers and runs headless in CI.

npm i -D @playwright/test && npx playwright install chromium

Start the app first and hold the port — a test suite against a dead server produces a wall of timeouts that tells you nothing: