How do I test async code in Jest?

How do I test async code in Jest?

To test async code in Jest, you can use the async/await syntax or return a promise from your test.

Can you show me an example of testing a function that returns a promise?

Sure! Here's a simple example:

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

What if I want to test an async function that throws an error?

You can use expect().rejects to test for errors. For example:

await expect(fetchData()).rejects.toThrow('Error message');

Are there any specific Jest matchers for async testing?

Yes, Jest provides matchers like resolves and rejects to handle promises easily.