- Locate the changes in the source code and detect all the areas, components, and modules that might have been affected; analyze the impact of the changes on the existing functional and non-functional features; determine if the minimum conditions were met for the execution of regression testing.
- Based on the analysis, compile a regression test suite made of the test cases relevant to the changes and the affected areas; categorize them into small groups with concise descriptions to make it easier for your team to identify and prioritize certain types of tests.
- Prioritize the tests based on the severity of the impact (critical, high, medium, or low) the changes had on your functional and non-functional features. This will help you optimize your testing workflows to focus on dealing with the most problematic cases first, ones that hinder further development.
- Plan and maintain a strict schedule for continuous regression testing throughout your software development life cycle. Find the right timing to perform the testing in a way it doesn’t cause any setbacks in development.
Best practices of regression testing
Whether you are planning to perform regression testing with your own company’s resources or opt for an outsourced software testing team, there are always ways to make your regression testing efforts more efficient. These are the main best practices for regression testing:
- Implement regression testing frameworks. They will make all testing-related processes more streamlined, help onboard new teammates, and make maintenance easier.
- Introduce testing automation. Automating some or all of the regression test cases takes time and calls for experienced AQA engineers, but the long-term benefits are hard to argue with.
- Keep your test suite up-to-date. When your test suite only contains cases that are regularly maintained and relevant to the project, maintenance becomes easier and testing becomes more effective.
- Prioritize your test cases. Over time, the regression test suite can grow significantly even with regular maintenance. However, testing the whole suite time and time again often takes more time and effort than the team can afford, which is why it’s important to select the most appropriate and frequently used cases for testing.
- Make full regression testing a collaborative effort. Although regression testing is primarily performed by testing engineers and AQAs, using input from software developers, end users, and other stakeholders results in a higher quality of products.
When you perform regression testing
Ideally, regression testing should be performed whenever your codebase has been modified or altered in any way as well as to verify any previously discovered issues marked as fixed. The more often the better: frequent partial regression testing will help your developers fix the reported defects on time, and your project to avoid any long-term pitfalls and technical debt caused by poor code quality. However, even though an occasional project might have the resources to perform the tests after the slightest changes have been introduced to the codebase, for most projects designing and maintaining such a multiplicity of regression tests may simply be infeasible. Therefore, it is important to understand when you need to start regression testing.
The most common reason to run regression tests is the introduction of new functionality. It is hard for developers to follow every thread in the code when modifying it, and there’s always a risk of compatibility issues with the existing code. Regression testing can save developers a lot of time with timely detection of bugs that would otherwise cause the project a lot of pain in the long run.
Sometimes, however, sudden shifts in business strategy and requirements can lead to complete revision of the existing functionality, which requires developers to adjust, reshape, or even discard some of the features. Heavy interference with the source code can potentially cause a lot of damage to the remaining functionality, which makes regression testing an absolute must in such cases.
Attempts at fixing one bug can at times turn into even more bugs appearing in codebase areas you expect them the least. Debugging suggests making a lot of big and small changes to the source code, checking bug statuses, and going through the same process over again. This, in turn, points out the importance of following up the debugging stage with regression testing to guarantee it didn’t cause more issues than it fixed; to make sure everything works as intended after debugging. Last but not least, regression testing has proven to be an effective means of ensuring seamless and bug-free integration with external systems.
Manual vs automated regression testing
Where some particular issues may require the utmost precision and time efficiency of automated regression testing, some defects would be unable to fix without the human critical thinking and creativity applied in manual regression testing. Hence, the key to cost-effective, productive regression testing is finding the right balance between the two approaches that deal with different issues.
Sometimes working on test automation is not worth the effort, especially when we’re talking small projects and simple software solutions built in 2-3 months. In this case, QA engineers can easily perform manual regression testing, using such bug-tracking tools as Jira and Code Quality for Jira. Manual regression testing is a pretty basic approach to testing software regardless of the product development methodology you’re using, and it always precedes automation as it provides more efficiency in the early stages of development.
Nevertheless, as the project scales and grows with features, the scope of regression testing increases as well, which means manual testing becomes significantly less efficient and more time-consuming. At some point, it simply becomes infeasible to manage the regression test cases manually and the team switches to automated regression testing. Once built, your automated regression suite can be easily reused—catching every defect with a press of a button—to the last bug eliminated, which is way cheaper and more reliable than putting your whole QA team through doing it manually. Another big plus is that it enables you to increase the frequency of your test runs and get immediate feedback. When it comes to QA teams, the reason they favor automated regression testing is that testers do not enjoy the process of running the same tests over and over again. Such repetitiveness inevitably affects the tester’s focus and performance. In contrast, automating the regression testing enables them to redirect their brainpower on tasks that require critical thinking and creativity.
Top 5 popular regression testing tools
Regression testing includes a wide variety of testing types, both functional and non-functional ones, to ensure the spotless quality of the software product. Regression testing is usually executed with the help of software tools. Some of them are specifically designed for regression testing, and others have a broader spectrum of uses. Here are the most popular tools used for regression testing.