Writing Type-Safe Unit Tests
Annotate test data and assertions with TypeScript types.
Welcome
Type-safe tests catch bugs in test code itself and ensure your test data matches your production types.
Typing Test Data
Use your types for test data — TypeScript will catch stale test data when types change.
import type { User } from '../src/types';
const mockUser: User = { id: 1, name: 'Alice', email: 'a@b.com' };
// TypeScript errors if User interface changes