Comparing Vitest and Jest: Which Testing Framework is Better?

If you develop in JavaScript, you have several options to test your code. Two of the most popular are Jest and Vitest.😁

Which is better, Jest or Vitest?

It depends on how you manage your code modules, your development environment, and how much you value test speed.

Let's take a look at the differences between Jest and Vitest and help you decide which is best for your needs.

What is Jest? Jest is a testing framework for JavaScript that supports major frameworks like Vue, Angular, React, and Node. Built on top of Jasmine, Jest has some extra features like native support for mocking.

Created by the folks at Facebook (now Meta), Jest is now an open-source project of the OpenJS Foundation. So, the main difference between Jasmine and Jest is more about features than who maintains them.

Benefits and Features of Jest

Jest is not that different from other testing frameworks, but it has some highlights:

• Integrated support for mocking

• Snapshot function to compare test results

• Parallel tests to reduce execution time

• Minimal configuration required

These features make Jest a good choice for those seeking simplicity and some advanced functionalities.

What is Vitest?

Vitest is a unit testing framework for JavaScript created to complement Vite, a build tool for web applications. You can use Vitest without Vite, but it is more laborious to set up.

Compatible with the Jest API, Vitest focuses on speed. If you use Vite, Vitest will save you a lot of time with automatic configurations.

Benefits and Features of Vitest

The big takeaway of Vitest is the speed. Some tests in Vitest can be up to 4 times faster than in Jest. Additionally, the integration with Vite makes life much easier.

Jest vs. Vitest

Both are great modern, simple, and fast frameworks. But some differences might influence your choice:

• Testing Capabilities: Both support testing JavaScript code with almost any modern framework.

• Speed: Vitest is generally faster, especially if you run many tests in a resource-limited environment.

• Module Management: Jest handles CommonJS better, while Vitest is better with ECMAScript Modules (ESM).

• Documentation and Support: Jest has a larger community and more support resources, but Vitest is growing fast.

Conclusion

If you use Vite and want speed, go with Vitest. If you need something more flexible and with more support, go with Jest. In the end, both are excellent choices for testing your JavaScript code.

That's all for today folks!

See u in next week :-)

Eduardo Burko - phantodev.com.br