Top 5 awesome Testing libraries for Javascript

Javascript is one of the most popular programming languages among developers supporting web, mobile, and desktop applications. As our applications are getting big handling millions of concurrent users, it is not very easy to manage such a complex code base which needs to be perfect before pushing it to production. Thus need for smart automated testing libraries for JavaScript has surged exponentially.

In this blog, we will see the top 5 carefully curated excellent testing libraries for Javascript which you can use in order to make your application error-free.

Different types of Testing Methods

Before moving forward to learn awesome testing libraries we can use to test performance and make our application bug free. We need to understand are different types of testing methods and which method would be more beneficial for our requirements.

Unit Testing

Unit testing is a way to test each individual component like functions where we pass a few edge cases and check if we are getting the expected output or not.

End-to-end Tests

End-to-end tests or E2E Tests or Functional Tests is a testing method in which the user creates a scenario for the application on the browser and controls each step accordingly.

This type of test is generally applied when your application is nearly completed and you want to check the application experience. All the internal work is totally ignored and the focus is more on the experience when user input data and get expected or not, generally treating the whole application as a black box.

Integration Testing

Integration testing is a method of testing the collection of components to check their collective goal and also learn their side effects.

Also read, What is JavaScript Event Loop?

Top 5 awesome Testing libraries for Javascript

Mocha

Mocha is a feature-rich Javascript testing framework meant to be used for testing applications running on Nodejs. It is very easy to install but requires a number of steps to configure.

Why Choose Mocha?

• Mocha has highly extensible with numerous mocking libraries.
• Testing asynchronous functions are accessible. 
• It supports generators with ease.
• It provides a greater facility to handle exceptions with the number of test cases.

Cons

• Configuring at the initial step is a bit lengthy and complex

Also read, How JavaScript works with HTML you might not know

Jest

Jest is one of the most popular testing libraries for Javascript, rated no 1 JavaScript automation testing framework for 2018 by the stateofjs survey. Jest has been developed by Facebook and Jest is also the first choice of many developers to test their React applications.

Why Choose Jest?

• Configuring and onboard setup is minimal and hassle-free.
• Jest offers amazing developer tooling options. 
• Jest has well comprehensive documentation and good developer supports.
• Different tests can be run parallel maximizing the performance.
• Jest also comes with a lot of useful features like snapshots and a test watch.

Cons

• Jest for some developers may have a hard learning curve.
• Snapshot for larger files is not feasible.

Also read, What is JavaScript Event Loop?

Cypress

Cypress is a modern next-gen front-end testing tool built for the new-age web. It allows users to write unit tests, end-to-end tests, and integration tests easily. Cypress has been built using Javascript and only works with the Mocha testing framework.

Why Choose Cypress?

• Cypress is very compatible with frontend development and its major point is that with the help of cypress you can also modify DOM elements directly.
• Cypress takes a snapshot at every step, which allows developers to track the development at each step. 
• It is a very reliable testing framework providing consistent results.
• All the tests of cypress are executed in the browser itself which removes the possibility of network lag or freezing.

Cons

• Cypress only supports javascript frameworks for test case creations.
• It does not support any remote execution.
• It does not support multiple browser tabs simultaneously.

Also read, JavaScript Functions | How does Function works in Js {Detail Explanation}

Karma

Karma is a test runner framework, especially for Angular and its main objective is to create a productive testing environment for the developer. It puts less burden on the developer by simplifying the configuration process and also provides instant feedback from their test cases.

Why Choose Karma?

• Karma is best for automation testing on real devices and browsers.
• Karma comes with an interactive IDE where you can control the entire workflow.
• Karma is very compatible with Mocha and Jasmine.
• Karma is an open-source testing framework with wide developers’ support and a big community.

Cons

• Karma is not a full fledge framework or library but rather a test runner environment that can easily be provided by other testing libraries.

Also read, What is a Callback Functions in JavaScript

Jasmine

Jasmine is a feature-rich Javascript automation testing framework that is mostly used for asynchronous testing processes. It is an independent behavior-driven testing framework for javascript with easy-to-learn syntax.

Why Choose Jasmine?

• Jasmine comes with minimal configuration and zero dependencies on another library.
• Jasmine runs on Nodejs and provides accurate and flexible bug reporting in which all the tests are run serially.
• Jasmine is highly compatible and flexible with every framework and library of Javascript.
• Community support and documentation are also quite large.
• With comprehensive documentation, the learning curve is also very small.

Cons

• Setting up a configuration file is a bit more complicated than Jest, where you have to create a test.js configuration file before running test cases.

Also read, How to debug JavaScript in browser?

Final Words

I hope you like the specially curated list of awesome testing libraries for javascript, in which we discussed different types of testing frameworks which we can use in order to test and debug our application.

Do share this article among your friends and colleague if you found this article helpful and also do check out more articles on various topics like Data structure and algorithms with javascript, Java, React, and Javascript.