If your organization is interested in software development, you have likely heard the term regression testing. Regression tests are an essential part of the software development process and ensure that software products function correctly as they change.
If you have active software being updated to fix bugs or add new features, your organization must perform regression testing. This post will explain the regression testing process and its importance.
In addition, we will also examine the most popular and widely used regression testing techniques. Complete regression testing is vital to the success and longevity of your organization’s software.
What Is Regression Testing?
Regression testing is a type of software testing that is utilized any time code changes are made to a software system. Regression tests ensure that new code changes have not introduced new bugs or caused new breaks in the software’s performance.
Code changes can bring new logic into the software that conflicts with existing code, leading to bugs and other potential defects or vulnerabilities. Typically, teams will regression test their code after every significant update.
In addition, automated regression testing can be utilized to regression test standard features automatically every time a change is made to the code. Automated regression testing saves time and maximizes the efficiency of the development team.
The Importance of Regression Testing
Regression tests are critical to the success of any software development project. Regression testing ensures that code changes do not introduce new defects or cause errors in the software.
Modern software development is often fast-paced, thanks to the utilization of Agile methodologies. As a result, regression testing is vital to the ability of Agile teams to deliver high-quality software products without breaking their pace.
Regression tests allow developers to push new code with the confidence that they are not breaking vital features and components already functioning correctly. With regression testing tools, developers can develop test cases that look for specific errors that commonly occur to maximize efficiency.
These pre-built regression tests form a regression test suite that developers can use to quickly run test cases when changes to code are made. As the regression test suite grows, regression test selection becomes more important when efficiency is critical.
Finally, regression testing makes it easy for developers to determine where errors and bugs come from. If a project has a poor version control system, locating these errors and bugs without regression testing is difficult and time-consuming.
As regression tests become more routine, they are perfect candidates for automated testing. However, to maximize the effectiveness of automated testing, detailed test cases must be developed.
Regression Testing Techniques
There are a few techniques that are central to regression testing. While automated regression tests can be created with detailed test scripts, manual testing is often required for regression tests to be their most effective.
The top techniques used in regression testing include the following:
- Retest everything
- Test selection
- Test case prioritization
- Corrective regression testing
- Progressive regression testing
In this type of regression testing, all available test cases are checked. This type of regression testing suite is the most effective and safest way to ensure that all bugs, defects, and errors are identified.
However, the retest everything approach is resource and time-consuming. Some projects will have a lot of test cases to run, and the complete regression testing approach can take more time than businesses are willing to spend.
Many organizations choose to pursue complete regression testing when they make application-wide updates, make adjustments for a new platform or programming language, or make a significant update to the operating system.
If you have a small application, complete regression testing is also a great option because there are only a few existing test cases to run. When the amount of test cases increases, complete regression testing becomes more costly and time-consuming.
In this approach to regression testing, QA teams choose specific unit tests to run. Functional tests are prioritized for the features and components most impacted by changes to the code.
By being selective, teams can run the most critical test cases and work more efficiently. While this selective approach to regression testing is often utilized in large, complex applications, the downside is that by not running all regression test cases, you could miss something.
However, if issues are discovered in parts of the application that were not tested, additional functional testing can be performed to iron out issues. If your team pursues a selective approach to testing, they need to ensure they are choosing suitable test cases.
Test Case Prioritization
This approach to regression testing prioritizes the test cases that must be performed first. Organizations prioritize test cases on several different criteria. However, the most common points businesses should consider when prioritizing test cases include:
- Failure rate
- Business impact
- Security impact
- Customer impact
Every business will weigh specific priorities differently. However, test cases that fail at a high rate or have a significant business impact should be prioritized above all else. Understanding which elements of your application are critical for business success is necessary.
Corrective Regression Testing
Corrective regression testing involves running all test cases when no code changes have been made. Corrective regression testing not only double-checks that the software’s code is performing as expected, but it also validates the existing test cases.
Knowing whether or not your team is using practical test cases is an integral part of regression testing. If you have inadequate test cases, you can’t be sure that you’re catching all of the potential errors and bugs in your code.
Progressive Regression Testing
Progressive regression testing acknowledges that changes in code might require changes in test cases. Progressive regression testing involves updating test scripts to keep pace with the implemented code changes.
Once again, progressive regression testing validates that your teams use the suitable test cases during testing. As noted, using the correct test cases is an integral part of successful regression testing.
What are the Top Regression Testing Tools?
To conduct efficient regression testing, testers often rely on various tools and frameworks that automate the testing process and help identify any unintended side effects of code modifications. Here are some of the top regression testing tools in the industry:
- Apache JMeter
- Tricentis Tosca
Selenium is one of the most popular open-source tools for automating web applications. It supports various programming languages like Java, Python, C#, and more. Testers can create scripts to simulate user interactions with a web application, making it suitable for functional and regression testing.
JUnit is a widely used testing framework for Java applications. While primarily associated with unit testing, it’s also valuable for regression testing when combined with other tools and frameworks. It allows testers to create and run test cases, making it a staple in Java development environments.
TestNG is another testing framework for Java that is designed to cover a broader range of testing scenarios than JUnit. It supports parallel test execution, data-driven testing, and advanced annotations, making it a powerful choice for regression testing in Java projects.
Jenkins is a popular open-source automation server that can be used to automate various aspects of software development, including regression testing. It integrates with many testing tools and can be configured to trigger regression tests automatically whenever code changes are pushed to a repository.
Apache JMeter is an open-source tool designed for performance and load testing. While its primary focus is not regression testing, it can be used to conduct regression tests for web applications by simulating multiple users and monitoring performance metrics.
Postman is a popular API testing tool that allows testers to create and automate API tests. It’s essential for regression testing when dealing with web services and APIs. Postman provides a user-friendly interface and supports scripting to perform complex tests.
SoapUI is another tool primarily focused on API testing, especially for SOAP and RESTful web services. It offers a comprehensive set of features for regression testing, including data-driven testing, security testing, and load testing capabilities.
Cucumber is a behavior-driven development (BDD) tool that enables the creation of executable specifications in plain language. It is particularly valuable for regression testing because it enhances collaboration between developers, testers, and non-technical stakeholders.
Tricentis Tosca is a comprehensive test automation platform that supports end-to-end testing, including regression testing. It offers many features, such as model-based test automation and test case design, making it suitable for complex regression testing scenarios.
Regression testing is an essential part of software development and Quality Assurance. There are many different techniques and tools that can be used to simplify regression testing and focus its efforts on the areas that will have the most significant impact on your application and business.