What are the best practices for testing TypeScript and Express applications?

What are the best practices for testing TypeScript and Express applications?

When testing TypeScript and Express applications, consider using tools like Jest for unit testing and Supertest for API testing.

How do I set up Jest for a TypeScript project?

To set up Jest, install it along with the necessary TypeScript types, then configure your Jest settings in a jest.config.js file.

What about integration testing with Express?

For integration testing, you can use Supertest to simulate HTTP requests and test your Express routes and middleware.

Can you give an example of a test case?

Sure! Here's a simple test case using Jest and Supertest to test a GET endpoint:

import request from 'supertest';
import app from './app'; // your Express app

test('GET /api/users', async () => {
  const response = await request(app).get('/api/users');
  expect(response.status).toBe(200);
});