React has become one of the most loved JavaScript libraries in the app development industry. Developers have grown quite fond of it and why shouldn’t they? After all, it does have several amazing features along with a rich ecosystem that includes a variety of tools and numerous ready-to-use frameworks.
So when it comes to testing React applications, you can rest assured that there are some top-notch tools and frameworks for that too. Most of these frameworks have powerful features and impressive tooling that help React developers ensure code reliability, quick debugging, and seamless development.
But as tempted as a developer might become to experiment with the frameworks, it’s not wise to do that given not all frameworks deliver optimum results. That’s why we have picked seven useful testing tools and frameworks that help React developers create flawless apps. Let’s get to know them.
- JEST
Jest has a record of more than 15 million downloads per week which qualifies it as the default and the most popular choice for testing React apps. Created and supported by Facebook, it is used to test almost all JavaScript codes. Jest’s efficacy is fortified by the fact that renowned names like Uber and Airbnb also use it.
Jest is great for beginners who are trying to get acquainted with JavaScript really fast. The competitive features that make it a useful framework are:
– Snapshot testing and test management of larger objects with live snapshots
– Parallel test execution
– Powerful mocking capabilities
– Built-in support for testing React components
– Integration with other potent tools like Babel and ESLint
- JASMINE
Jasmine is a popular BDD (Behaviour Driven Development) testing framework used for testing all sorts of JavaScript apps, including React. One of its biggest advantages is that it can be used for both response and visibility tests of the UI across different devices.
Jasmine is loved because of its expressive and readable syntax that enables programmers to write tests in a human-readable format. Its other highlighted features include:
– Built-in assertions
– Ability to create mock objects
– Test organization and reporting
– Asynchronous testing support
– Built-in support for test spies
– Highly active and growing community
- MOCHA
Mocha is another widely-used testing framework for React. It’s popular for its extensibility, simplicity, and its compatibility with various testing styles, including BDD and TDD (Test Driven Development).
Mocha also offers support for custom interfaces and reports which enable developers to tailor tests according to their specific needs. Other important features of Mocha are:
– Wide range of assertion libraries
– Test organization and reporting
– Integration with other libraries like Should.js, Expect.js, and Chai
– Support for browser-based testing environments
– Support for Node.js testing environments
– Extensive documentation and rich ecosystem
- KARMA
Karma is a test runner for JavaScript (neither a framework nor a library) that is commonly used for running unit tests in web development projects. It has a flexible and configurable environment for executing JavaScript codes in various browsers and platforms.
It launches the specified browsers, loads the test files, and captures the results. Other key features and concepts of Karma include:
– Simultaneous testing on multiple browsers (including Chrome and Safari)
– Integration with popular CI tools like Travis CI and Circle CI
– Watch Mode to monitor test files
– Integration with code coverage tools like Istanbul to generate coverage reports
– Highly configurable
- CYPRESS.IO
Cypress is an end-to-end, and open-source testing framework that allows developers to write tests without needing any additional framework. It offers a JavaScript-based API with which developers can write tests that simulate user interactions.
Based on those interactions, developers can assert the behavior of their web apps. Cypress works directly in a browser and houses a rich set of features that helps in carrying out testing efficiently. Some notable features of this testing framework are:
– Time-travel debugging and snapshot testing
– DOM stubbing
– Cross-origin testing
– Automatic waiting and automatic reload
– Support for CI/CD pipelines
- CHAI
Chai is an assertion library for JavaScript that consists of powerful, expressive, and flexible assertion syntax. Furthermore, its expressive and customizable nature makes it a preferable choice among developers as it helps them write clear and concise tests. A few other notable features that make it popular are:
– Multiple assertion styles
– Modularity and extensibility (with custom plug-ins)
– Wide range of assertion methods
– Integration with other testing frameworks including Jasmine and Karma
– Supports both BDD and TDD
- ENZYME
Enzyme is a JavaScript testing utility framework. Designed and supported by Airbnb, it can be used in combination with other powerful testing frameworks like Mocha and Jest for testing React components. It also helps developers simulate user interactions and assert behavior. Some of Enzyme’s valuable features include:
– Shallow and static rendering
– Full DOM rendering
– APIs to interact with rendered components
– Use of react-hooks (with limitations)
– Access to component prop and state
Summing Up
Testing libraries and frameworks play a pivotal role in delivering high-quality and reliable software. These tools also help in improving the overall development process by enabling developers to identify issues and rectify them in the early development phases.
When testing React apps, developers have multiple testing technologies to choose from. But the ones listed here cover several aspects of testing including browser, unit, and end-to-end. However, the best way to pick one is to check all the criteria that best suit a developer’s and the app’s requirements.