As developers write code, unit tests are typically written to ensure the code behaves as expected. Unit tests can be run automatically, and they can also be run manually. Many different unit testing tools are available, and choosing the right unit testing tool for your software development project can be quite challenging.
This programming tutorial will discuss unit testing, why it is crucial for developers, some of the most popular unit testing tools for programmers, and compare their features.
What is Unit Testing?
Unit testing is a fundamental process in developing high-quality software. By testing individual code units, programmers can verify that they are functioning as expected before integrating them into the more extensive code base. In unit testing, you test individual units of code, such as code snippets or methods.
When developers write code, they should write unit test methods to ensure that the code performs as desired. Unit tests are small sections of code that help you validate the functionality of a particular module or component within an application. These tests can be used to verify that individual elements work correctly or as regression checks after changes have been made to code.
Unit tests are also helpful in determining what needs to be improved or fixed (to improve performance, security, scalability, etc.) for your application to function in a high performant manner.
Top Unit Testing Frameworks
Developers can use unit testing frameworks to build unit tests, execute them, and report their results. The use of unit test frameworks is not limited to the development process. During the software development process, they can also be used during the design, debugging, performance optimization, and testing stages.
NUnit is one of the most popular unit testing frameworks for .NET ported from JUnit and has been around since 2002. NUnit is an open-source testing framework that lets you write and run .NET tests. You can run tests batch-wise using its console runner. It also allows you to run tests via Visual Studio using the Test Adapter. You can also use third-party runners.
The NUnit Test Engine powers the console runner to explore, execute, and load tests. Tests can also be run in a separate process using the NUnit-agent program. You can run NUnit on multiple platforms, such as .NET Core and .NET Framework. Besides running tests in parallel, it lets developers organize them into categories and run only those tests they select.
JUnit is a popular, open-source unit testing framework for applications built using Java and has become the de facto standard in the Java world. JUnit was originally created by Erich Gamma and Kent Beck in 1998 to test Java code as part of their research into Extreme Programming (XP). The two were working on a project called Extreme Programming, which required them to have a way of testing their code without having to run it all the time.
JUnit was their solution for this problem, and it has since become one of the most popular unit testing frameworks out there. Today, it is used to test all kinds of programs written in the Java programming language: from small applications to enterprise systems running on multiple servers. It should be noted here that JUnit 5 is the next generation of JUnit for unit testing in Java.
TestNG is a standalone Java testing framework developed by the same team that created JUnit. Many of its features were inspired by JUnit and NUnit, but it has been enhanced to be more powerful and easier to use and based on JUnit and NUnit. TestNG is a framework for writing automated unit tests for Java applications. By writing multiple test classes in one file, developers can manage all their test cases in one place.
xUnit.net, built by the authors of NUnit, is an open-source, free, side-by-side alternative for testing the .NET Framework. It is a data-driven unit test framework that facilitates working with data-driven unit tests. You can use this open-source unit testing tool with Visual Studio, ReSharper, CodeRush, and several other popular developer tools.
It has excellent extensibility for test classes and test methods. The xUnit test framework is widely regarded as one of the leading unit testing frameworks for .Net programming languages such as C#, VB.Net, and F#. In xUnit, structure and functionality are derived from Smalltalk’s SUnit.
SimpleTest is a unit and web testing tool and mock objects for PHP inspired by JUnit, the de facto standard Java unit testing framework. SimpleTest has been around since 2004 and works well with continuous integration services like Jenkins or Travis CI—you can even use it without these services if you want by running your tests manually each time they change.
Final Thoughts on Unit Testing Tools for Developers
Unit testing can help developers detect issues in their code much before the application is deployed to production. There are many different unit testing tools around – you need to select the right tool for your project based on your requirements, the platform, and technologies you or your software development team are using.