How can I use Testing Library to mock APIs in my tests?

How can I use Testing Library to mock APIs in my tests?

You can use the jest.mock function to mock API calls in your tests. This allows you to simulate API responses.

Can you show me an example of how to mock a fetch call?

Sure! You can do something like this:

jest.mock('node-fetch');
import fetch from 'node-fetch';

fetch.mockImplementation(() => Promise.resolve({
  json: () => Promise.resolve({ data: 'mocked data' })
}));

What if I want to test error handling?

You can mock the fetch call to reject with an error. For example:

fetch.mockImplementation(() => Promise.reject(new Error('API error')));

Are there any best practices for mocking APIs?

Yes, keep your mocks simple and only mock what you need for the test. Also, reset mocks between tests to avoid side effects.