Jest Testing Tutorial: 7 Easy Steps

Jest Testing Tutorial

Basic applications play a major role in improving the overall user experience. This is because these applications are very critical for improving the popularity of a company as these can be accessed by people irrespective of their technical knowledge. Jest was initially developed by Facebook to test the proper functioning of all React applications. However, with the popularity of this application, it began to diversify. In the present generation, developers can use this tool to test the proper functioning of both JavaScript-based front-end and back-end applications. This means the developers can use this tool to verify not only the appropriate functioning of all the elements present in the user interface but also ensure the core functioning of the application framework.

With this article, we’ll dive deeply into the world of Jest testing. We will try to understand the basics of this tool and its major benefits. Finally, we’ll also learn how to initiate Jest automation test cases with the help of seven simple steps.

Basics of Unit Testing

Unit testing is often regarded as the basis of automation testing for new developers; automation testing is initiating automated test cases that can execute automatically with the help of predetermined data and parameters. While using automated test cases, the developers also have the freedom to change the parameters in the text file to customize the testing process according to the requirements of the application development process at hand. While executing unit testing, the developers have to separate all the individual segments of the web application into smaller components. These components are often referred to as units. Since every element is tested separately, it is easy to design the test cases accordingly. Many experts believe that unit testing is the best to get started with automation test cases.

The unit test cases are not only very fast to execute but also have a relatively easy setup process. They do not require any form of an elaborate setup and learning process. Lastly, the unit test cases provide a very precise feedback mechanism. This means developers can easily execute the debugging processes following the testing process.

Base of Jest

In simple terms, we can define Jest to be a popular test automation framework for executing all applications that are based on the JavaScript programming language. Many experts believe that Jest provides a delightful testing experience for all applications that depend on JavaScript. It also provides a simple and hassle-free experience for all the new developers who are transitioning to automation testing processes. Currently, many major companies like Instagram, Pinterest, and Twitter use Jest for performing react test cases. The developers must remember that Jest itself is not a library but a testing framework. The CLI documentation of Jest provides much more functionalities that help the developers to execute multiple testing processes that follow a specific pattern.

To summarize all the features of Jest, we can say that it provides the developers and testers with a test runner assertion library, great support for different mocking techniques, and a CLI tool. Combining all the features mentioned above, we can easily say that it makes Jest not just a testing library but a complete framework.

Benefits of Using Jest

Before discussing the testing techniques with Jest, it is very important to have a complete idea about the benefits of this test automation framework. This is because, with the help of this knowledge, developers can make all the calculations regarding utilizing the full potential of this framework. So based on our research and analysis, the major benefits of using Jest are as follows:

  • The CLI tool of Jest allows the developers to control all the test cases natively. This means it helps to eliminate the hassle of integrating any third-party tool for this dedicated process. This is yet another step in improving the simplicity of the test cases.
  • The interactive mode of Jest allows the developers to automatically analyze all the tests affected by a native code change. After this process, the system will automatically run the test cases and ensure they execute correctly. The system will continue to repeat this process as long as the developers and testers make changes in the code. It is a very beneficial feature for applications undergoinga rigorous updating process.
  • The Jest syntax allows the developers to run one test at a timeand ultimately skip the test cases if required. The developers can initiate these features with the help of dedicated commands in the terminal window. This process is highly beneficial when the developers are working on custom applications that require all of these features.
  • The official website of Jest provides a lot of documentation to help developers get started with the installation and test initiation process. It also has a massive community of tech enthusiasts who are always ready to help new developers. The official website also provides multiple documentation and sample test cases explaining the working of all the available featureswith this automation testing framework.
  • Test mocking is one of the most painful processes when the developers must conduct it manually. However, with the help of Jest, the developers get native support for this process out of the box. So, it not only helps to save a lot of hassle but also improves the efficiency of the testing processes.

7 Easy Steps to Learn Jest Automation Testing

Jest is one of the easiest test automation frameworks to get started with. The new developers can start automation test cases with Jest by following only a few simple steps. Based on our analysis and research, we have explained the Jest automation testing process with the help of the following steps:

  1. The first step is to install Jest globally. With the help of this process, the developers can gain native access to the Jest CLI.
  2. During the Jest installation process, the developers must ensure that they have Node.JS installed on their system. This is because node.JS will help the developers to access NPM. One of the most important things to remember during the installation process is to not only install the latest version but also access all the files from the official website. This will prevent any risk of data security or privacy breach.
  3. After this, the developers have to create a simple NPM-based project. This project will house all the production and test codes. It will also help the developers to have the package. JSON file inside the test folder. The final step in this process is to create a file named index.JS and paste specific content into it.
  4. After the developers have created and configured the project file, itis time to integrate Jest with this file and folder. The easiest way to integrate Jest is to introduce it as a dev dependency. To accomplish this, the developers simply have to write a specific command in the terminal window.
  5. Now, the developers are ready to write their first Test case with Jest. During this process, we recommend the developers have a specific idea about the working mechanism of the Jest syntax. This is because this idea will help the developers utilize the features’ full potential andhelp in the debugging process.
  6. After the developers have written their first Test case with Jest, it is time to returnto the terminal window and simply run the NPM test option. The test will run for a specific amount of time and display the result in the terminal window.
  7. After the developers knowabout the failed and passed test cases, they can easily move on to the debugging processes with Jest. Jest also helps the developer to keep track of all the test cases and the specific code bases that have given an error. It is a very important process for easily tracking the issues and bugs with the application and solving them quickly.

Role of Tools and Platforms to Improve Jest Test Automation

Various tools and platforms can help developers easily initiate and execute the Jest test automation cases. For instance, certain tools help the developers to integrate the Jest automation test cases with Selenium. Moreover, these tools help the developers to eliminate the need for an on-site device testbench with the help of cloud-based testing. In simple terms, we can define cloud testing as a process of initiating and executing test cases on multiple cloud devices over the web. So, it eliminates the huge expense and time needed to create such onsite test benches. To improve our knowledge, we can consider the example of LambdaTest as it helps the developers to accomplish both of the above goals:

LambdaTest is a cloud platform to verify the proper functioning of modern web applications. The primary path to achieving this goal is the execution of cross-browser testing. This is because cross-browser testing has become the modern market standard for ensuring smooth and highly efficient web applications. With the help of these test cases, the developers can provide the highest-performing apps despite multiple shifts in the OS version or device hardware. The Jest Selenium WebDriver of LambdaTest helps the developers to execute the automation test cases on an integrated secure cloud grid. LambdaTest also initiates parallel testing of multiple test cases further to improve the efficiency of the app development process.

The integration of Selenium helps developers to ensure the proper performance of the application on more than 3000+ browsers at the same time. Moreover, integrating real devices with multiple emulators and simulators helps developers generate highly accurate and dependable test results.

Final Verdict!

Considering all the points, we can easily say that Jest is one of the most important and efficient automation testing frameworks. With the help of this framework, the developers can ensure that all the web application components are functioning appropriately. The native support for the JavaScript programming language ensures that developers from all application testing backgrounds can access this framework. This is because JavaScript is currently the most commonly used programming language.

Moreover, many developers and experts believe that automation testing will become the native application testing trend of the future. So developers and app companies must keep themselves updated with all the modern automation testing practices. Lastly, we would like to mention that using multiple tools and platforms like LambdaTest is critical in improving the efficiency of Jest automation testing.