React has change into one of the vital widespread JavaScript libraries for constructing consumer interfaces, and because of this, the necessity for sturdy React testing frameworks and libraries has additionally elevated. Testing is an integral a part of the event course of, making certain that purposes are free from bugs and carry out as anticipated. On this article, we’ll discover a number of the prime React testing libraries that builders depend on in 2023 to check React parts and apps. We’ll study their options, and have a look at the professionals and cons of every.

In case you’re questioning “why check?”, otherwise you aren’t positive what unit checks are, check out our guide to JavaScript testing.

Desk of Contents
  1. Jest: The Preferred Testing Framework
  2. Mocha: A Versatile Testing Framework
  3. Jasmine: A Powerful BDD Framework
  4. Chai: An Assertion and Expectation Library
  5. Enzyme: A Powerful Testing Utility for React
  6. Cypress: A Lightning-Fast End-to-End Testing Framework
  7. React Testing Library: Testing User Behaviors with Ease
  8. Puppeteer: Automating Chrome Interaction

1. Jest: The Most popular Testing Framework

Jest is described as a “pleasant JavaScript testing framework”. It’s an open-source testing library developed and maintained by Fb. It has gained widespread adoption within the React neighborhood and is utilized by corporations like Airbnb, Uber, and Amazon. Jest is the default testing framework for testing React apps, making it a well-liked selection for builders.

Jest affords quite a lot of options that make testing in React environment friendly and efficient. It helps snapshot, asynchronous, and parallelization checks, permitting builders to simply examine the anticipated output of a element with its precise output. Jest additionally gives the flexibility to mock API capabilities and third-party libraries, giving builders extra management over their checks. Moreover, Jest includes a complete code and syntax report information, making it simpler to establish and repair points within the codebase.

Nevertheless, one limitation of Jest is its efficiency when used on giant initiatives that require various kinds of checks, corresponding to integration checks. To beat this limitation, builders usually use Jest at the side of different third-party testing frameworks like Enzyme.

To study extra about testing with Jest, check out our detailed guide.

2. Mocha: A Versatile Testing Framework

Mocha is one other widespread testing framework for JavaScript builders. It affords flexibility and permits builders to decide on their most popular assertion library and run asynchronous checks on their Node.js purposes. Mocha is appropriate with a variety of libraries and testing frameworks, making it a flexible selection to check React purposes.

One of many benefits of utilizing Mocha is its help for behavior-driven improvement (BDD) and test-driven improvement (TDD). When writing checks, it gives a straightforward option to write descriptive check instances and retains observe of check outcomes. Mocha additionally helps mills, making it handy to check suites when required within the check file. Many builders mix Mocha with Enzyme and Chai for assertions and mocking when testing React purposes.

We’ve a Mocha and Chai tutorial for those who’d wish to study extra.

3. Jasmine: A Highly effective BDD Framework

Jasmine is an easy but highly effective check framework for browsers and Node.js. It follows a behavior-driven improvement (BDD) sample, making it straightforward to jot down readable and expressive check code. Jasmine is broadly used for testing JavaScript apps, together with React initiatives.

One of many key benefits of Jasmine is its capability to check the visibility and responsiveness of consumer interfaces throughout completely different display screen sizes and resolutions. It’s usually utilized in mixture with Babel and Enzyme for React testing. Jasmine gives a customized equality checker and a built-in matcher assertion, giving builders extra management over their checks, and features a check runner. Nevertheless, Jasmine lacks help for snapshot checks, code protection instruments, parallelization (requires third-party instruments), and native DOM manipulation (requires third-party instruments).

You may learn extra about Jasmine in our article on testing JavaScript with Jasmine, Travis, and Karma.

4. Chai: An Assertion and Expectation Library

Chai is an assertion and expectation library for behavior-driven improvement (BDD) and test-driven improvement (TDD) in each Node.js and browsers. It really works effectively with any JavaScript testing framework, together with Mocha and Jest. Chai permits builders to specify their expectations for check outcomes utilizing its basic interfaces corresponding to anticipate, ought to, and assert.

When testing React purposes, builders usually use Chai at the side of different testing frameworks like Mocha and Enzyme. Chai gives a variety of assertion kinds and helps varied forms of comparisons, making it a versatile selection for writing checks. It’s particularly helpful when mixed with Mocha, because it gives a wealthy set of assertion and mocking capabilities.

We’ve a Mocha and Chai tutorial for those who’d wish to study extra.

5. Enzyme: A Highly effective Testing Utility for React

Enzyme, developed by Airbnb, is a JavaScript check suite particularly designed for testing React parts. It abstracts the rendering of parts, permitting builders to simply check the output of their React parts. Enzyme gives capabilities for element manipulation, traversal, and simulation of runtime habits, making it a robust software for React testing.

One of many benefits of Enzyme is its help for shallow rendering, which permits builders to check parts in isolation with out rendering their little one parts. It additionally gives help for DOM rendering, enabling builders to simulate real-world situations and interactions with parts. Enzyme is often utilized in mixture with different testing frameworks like Jest and Mocha to reinforce the testing capabilities of React purposes.

6. Cypress: A Lightning-Quick Finish-to-Finish Testing Framework

Cypress is a contemporary, end-to-end testing library that gives a seamless testing expertise for builders. It eliminates the necessity for studying a number of testing frameworks by offering a complete resolution for writing checks and operating them. Cypress permits checks to be executed in an actual browser or the command immediate, offering builders with a robust toolset for testing their React purposes.

One of many key benefits of Cypress is its snapshot time journey and video recording function, which permits builders to simply debug failing check instances. It gives an intuitive API for interacting with web page components and simulating edge situations with out the necessity for exterior proxies. Cypress additionally affords built-in parallelization and cargo balancing, making it simpler to trace down bugs and make sure the stability of React purposes.

Try our comprehensive overview of Cypress testing.

7. React Testing Library: Testing Consumer Behaviors with Ease

React Testing Library, created by Kent C. Dodds, is a widely-used check suite for React purposes. It permits builders to check React parts by simulating consumer behaviors and interactions. React Testing Library comes with built-in React DOM testing utilities, making it simpler to emulate consumer workflows and actions on a React software.

One of many benefits of React Testing Library is its help for each class and performance parts, making certain consistency in testing whatever the element kind. It gives APIs for querying components primarily based on textual content, label, show worth, function, and check ID, permitting builders to simply find and work together with components throughout testing. React Testing Library additionally affords a wait operate to attend for particular components to seem, making it helpful for testing asynchronous habits. Nevertheless, React Testing Library has limitations, corresponding to the lack to entry element state and the shortage of help for shallow rendering.

8. Puppeteer: Automating Chrome Interactions

Puppeteer is a headless Chromium Node library that gives an API for manipulating Chrome or Chromium by means of the DevTools protocol. It permits builders to automate interactions with a browser-like API with out the necessity for a simulator. Puppeteer can be utilized for capturing internet pages as pictures or PDFs, testing Chrome extensions, and performing consumer interface testing.

Though Puppeteer isn’t particularly designed for React, it may be used at the side of different testing frameworks to offer complete checks. It affords capabilities past easy snapshot technology and can be utilized to work together with internet pages, fill out varieties, and simulate consumer interactions. Puppeteer is especially helpful for testing single-page purposes (SPAs) constructed with React.

We’ve a information to getting started with Puppeteer.

Conclusion

In conclusion, it’s important to check React purposes to make sure their high quality and reliability. There are a number of testing frameworks and libraries accessible, every with its personal set of options and benefits. Jest, Mocha, Jasmine, Chai, Enzyme, Cypress, React Testing Library, Puppeteer, and React Check Utils/Check Renderer are among the many prime selections for builders in 2023.