Companies often conduct rigorous software testing to ensure their product or service is ready for release. However, software testing should not stop after launch. Regression testing, or software testing performed after editing the software, is vital to maintaining functionality and optimum user experiences. Understanding the basics of regression testing will help you make sense of regression testing and how it helps software companies with their quality assurance strategy.
What is Regression Testing?
Regression testing should be performed any time a change is made to software (like a bug fix) to ensure that no other parts of the software have “regressed” from their previous functionality. By re-running both functional and non-functional tests after the software is changed, developers can confidently run their software without fearing the side effects of modified code.
Why You Need Regression Testing
Software code is modular; a code change can impact any part of the software that interacts with it. Regression tests safeguard against bugs resulting from other bug fixes. Regression tests reevaluate old and/or updated code. This ensures that the changes will not cause errors in previously functional code.
When to Regression Test Your Software
Any time software requires changes — whether by removing defects or by adding functionality — a regression test should be performed. This includes updates to the software itself as well as updates to any software it interacts with. For example, if software imports information from a business’s Customer Relationship Management (CRM) software and that CRM software updates, errors may result from the modification. In other words, the software regressed.
Regression tests are especially important in an agile environment. When interlocking sections of code constantly change, it’s important to ensure that these changes do not compromise the software’s functionality. The speed between sprints using agile development also means these regression tests need to be carried out quickly. Agile teams must, therefore, have a regression testing strategy in place from the beginning of development, and may want to consider automated regression testing, as well.
Regression Test Methods
Three main approaches to regression testing in an agile environment can help mediate the amount of testing needed with the amount of time needed to test: These approaches are the traditional regression test approach, the delayed week approach, and the delayed sprint approach. Each one has its pros and cons, and will require your software testing engineers to consider the goals of their regression testing strategy carefully. The traditional approach alternates sprints with end-to-end regression tests aimed at the changed code, while the delayed week and delayed sprint approaches facilitate continuous change and regression testing in unison.
Whatever approach you need, regression testing is a basic necessity of software quality assurance. Understanding the basics of regression testing can help you choose the right method for your software and improve the quality of its updates.