For this week’s blogpost I will be looking at an article from ReQtest that explains what regression testing is and its benefits. Regression testing ensures that previously developed and tested software applications are working the same as they were before recent code changes were done. Tests cases are re-executed to check to see if this occurs. Regression testing is needed when new features are added or when changes in requirements and code are modified per changed requirements. Bug fixing and fixing performance related issues are also instancing of when regression testing is needed. When a system is changed errors may arise, this is when regression techniques come into play.
- Retest All: this re executes all the tests that exist in the test bucket. This usually requires a large amount of time and resources making a very expensive resource.
- Regression test selection: this executes the selected part of the test suites for example re-usable test cases or obsolete test cases
- Test case prioritization: Prioritization of test cases depends on business impact and used functionalities.
The benefits of regression testing come from its basic idea, when your system is not working prior to changes made. Regression testing increases the possibility of tracking bugs caused by these new changes. It also helps in finding unwanted side effects that might have been caused due to a new operating environment. Of course, this will help identify bugs and errors in the early stage as well. Where this probably shines the most is when constant changes are required in the product. There are different types of regression testing as well. Corrective regression is used when there are no changes introduced in the existing product specifications, usually used to conduct a desired test. Progressive Regression is used when modifications are added in the specifications of the product and new tests cases are created. There are many more types of regression testing that is listed in the article such as Selective, Retest-All and complete regression. Some of the best tools for regression testing are WinRunner, QTP, vTest, Regression Tester and AdventNet QEngine.
All and all I thought this article was very informative, as I learned about a new testing method I have yet to learn or know about. It also seems to be very important especially if your system is working then after a change something goes wrong after said change occurs.