When it comes to testing, checking a single function is different from testing a complete application at once. It helps to understand the flaws in any units of the application and allows the developers to take appropriate steps.
How unit tests beneficial to you?
Testing a single functionality is often referred to as unit testing. It is done to ensure that every individual function performs as expected. A unit test verifies and substantiates the behavior of a particular unit of the application. Simply put, the unit test verifies if the isolated part of the software in the codebase behaves as interpreted and expected by the developer.
Unit testing helps developers compare the actual behavior of the software unit in complete isolation with the expected behavior. The term complete isolation here denotes that the developers do not connect the software unit under test with the external dependencies. For example, devs do not connect MySQL database with PHP, a filesystem, or any HTTP services.
Unit testing makes the coding and development process more agile. On Adding more features to the application, developers sometimes need to change its previous specification, which affects the overall functioning of the software. To detect this during development time, developers perform unit testing on each event of addition or deletion of features.
Web developers also focus on unit testing to improve the quality of code by identifying defects and errors before sending the application for integration testing. The overall process helps facilitate modifications and simplifies integration. The accuracy of each unit is tested to ensure no discrepancies remain in the code and everything is up-to-the-mark.
An assertion library that runs on web browsers and Node.js. This framework supports an array of unit test running platforms used for e2e and ui-tests.
Unit.js is open source and can be used for business as well as personal projects. Developers can generate and download API spec documentation from the unit tests into HTML, JSON, and Markdown for easy understanding and processing.
You can see an example usage of Jest here.
Cypress is popular mainly because it doesn’t demand a setup. With an interactive interface, the framework runs on browsers and is highly supportive of Windows, Mac, and Linux operating systems. The test runner automates video capturing and screenshots.
Once, Mocha was considered to be the best testing framework for unit testing, but the demand records declined with the introduction of other advanced and high-end testing platforms.
Developers can use Mocha for testing front-end as well as back-end platforms. It provides a clean base for writing codes and can mock objects for performing flexible tests. Mocha is also considered an ideal testing platform for large projects.