What is snapshot testing and how does it work in different frameworks?

What is snapshot testing and how does it work in different frameworks?

Snapshot testing is a technique used to ensure that the output of a component remains consistent over time. It captures the rendered output of a component and saves it as a snapshot. When the component is tested again, the new output is compared to the saved snapshot to check for changes.

Can you give examples of frameworks that support snapshot testing?

Sure! Popular frameworks that support snapshot testing include Jest for React applications, Mocha with Chai for Node.js, and Vue Test Utils for Vue.js.

How do I implement snapshot testing in Jest?

To implement snapshot testing in Jest, you can use the toMatchSnapshot() method. First, render your component, then call this method to create a snapshot. On subsequent test runs, Jest will compare the current output to the saved snapshot.

What are the benefits of using snapshot testing?

The benefits include catching unexpected changes in your UI, simplifying the testing process, and providing a clear visual representation of component output.