What is snapshot testing in React?

What is snapshot testing in React?

Snapshot testing in React is a way to test the rendered output of a component by saving a snapshot of it and comparing future renders to this snapshot.

How do I implement snapshot testing in my React app?

You can implement snapshot testing using Jest and the react-test-renderer package. First, install them, then create a test file for your component.

Can you show me an example of a snapshot test?

Sure! Here's a simple example:

import React from 'react';
import renderer from 'react-test-renderer';
import MyComponent from './MyComponent';

test('renders correctly', () => {
  const tree = renderer.create(<MyComponent />).toJSON();
  expect(tree).toMatchSnapshot();
});

What should I do if my snapshot test fails?

If a snapshot test fails, it usually means the component's output has changed. You can either update the snapshot if the change is intentional or investigate the component for unintended changes.