How do I test asynchronous code using Jest and Mocha?

How do I test asynchronous code using Jest and Mocha?

You can test asynchronous code in Jest using async/await or returning a promise. In Mocha, you can use the done callback or return a promise.

Can you give me an example of testing a promise with Jest?

Sure! Here's a simple example:

test('fetches data from API', async () => {
  const data = await fetchData();
  expect(data).toEqual(expectedData);
});

What about testing async functions in Mocha?

In Mocha, you can do it like this:

it('should return data', function(done) {
  fetchData().then(data => {
    expect(data).to.equal(expectedData);
    done();
  });
});

Are there any differences in handling errors in async tests?

Yes, in Jest you can use try/catch with async/await, while in Mocha, you can pass an error to the done callback.