What Is Regression Testing? Definition, Types, Advantages & More

Regression Testing

What Is Regression Testing?

Regression testing is a form of software testing with the goal to ensure that any code change, update, or quality improvement measures have not affected the functionalities of the product. For an easier and clearer understanding, you should know that Regression testing is nothing but some or all test cases from a few specific existing test suites. Those test cases are re-executed to check if the old code is still working after multiple small or big changes are made to it.

Well, if you try to understand the complete scenario, you must know that you have to keep making changes and adding new features to the code to keep your product up-to-date and highly efficient. And, being a tech person, you also know that even a small mistake can make huge differences in the functionality of the product or better to say, can introduce numerous bugs. You can know a lot about such mishaps in the article “What Is Software Testing? Definition, Basics, Importance, Types & Method”.

However, you cannot let the bugs stay as they can break down your product’s existing functionality as well as your business’s reputation. That’s why regression testing is performed with high priority for achieving the highest level of quality assurance for your product. Also, you must keep in mind that every new change in a product goes through multiple levels of testing before getting integrated with the main development branch. Regression testing is considered the final level that makes sure that the new changes do not bother or harm the existing product.

Importance of Regression Testing

Though we already saw that the primary objective of regression testing is to ensure that any change made to the code does not harm the existing features at all, there are many more crucial points that make regression testing highly important. Hence, we must get to know them here.

  • Testing is a time-consuming part of the software development process as well as the entire journey of a product. Quick and informative feedback received through the regression testing helps the testers make improvement strategies quickly.
  • Automated regression testing leads to a quicker re-run of the test cases and faster bug fixes.
  • Though functional testing is a great choice for checking the performance of the new features, to ensure their compatibility with the existing functionalities, you must execute efficient regression test suites.

These are the reasons behind such immense popularity of regression tests in the types of software testing. We must also mention that in modern agile methodologies, there is no scope for manual testing in most types of tests. You must use an effective test automation tool like PreFlight to reach the highest levels of automated software testing without dealing with even a little bit of coding.

When Should You Perform Regression Testing?

Here, we are listing down the suitable test scenarios for regression testing.

  • Whenever you add a new feature or functionality.
  • Whenever some modifications are done to an existing feature or a new requirement is added to it.
  • Whenever any change is made to the codebase for fixing existing or new bugs.
  • Whenever any kind of operation or optimization is done to the source code for performance enhancements.
  • Whenever you make changes to the configuration.
  • Whenever you add patch fixes.

Types of Regression Testing

Based on the testing requirements and how you deal with the test parameters, regression testing is categorized into six types. We are jotting them down to help you understand their suitability for you and make your pick.

Corrective Regression Testing

Though the primary situation for regression testing to occur is when there is some change in the source code, sometimes you just have to check the performance of the existing functionalities even if the source code hasn’t been affected at all. In such cases, you have to re-run the existing test cases and there is no need to write new ones. This is what corrective regression testing is all about.

Progressive Regression Testing

This type of regression testing properly justifies its definition. Here you need to ensure that the newly added components do not harm the functioning of the old ones. For that, you need to modify the testing requirements and create new test cases accordingly. Whenever you add a new component to the application, progressive regression testing is the best choice for you.

Selective Regression Testing

Though we have discussed this working method in the “Test Case Selection” part, we must mention that this type of regression testing is highly efficient in terms of time and resource consumption. In this method, you just have to focus on the specific old test cases that you have selected for their direct relevance to your test objectives. Hence, the exemption of testing the complete system and focusing on the necessary part only saves you a lot of time, effort, and resources.

Partial Regression Testing

As the name suggests, this type of regression testing makes you select a part of all the test cases irrespective of their being new or old. Here, besides testing the new code, you also need to ensure that the old code is not affected. That’s why the selection of a part of the complete test suite makes this approach named “Partial Regression Testing” instead of “Selective Regression Testing”.

Complete Regression Testing

Here, you need to test the complete system at once. This type of regression testing is often compared with acceptance testing as here the primary objective is to check if the addition of new software modules is having an impact on the user experience of the application. This testing is one of the mandatory steps performed before the release of the product.

Retest-All

The name itself gives you the idea that this method involves rerunning the existing test cases. The whole point of this testing method is to check whether the new changes to the code have introduced any bugs to it. This type of regression testing is effective due to the fact that it covers all the components & functionalities present in the product but rerunning such a huge number of test cases makes this method insanely time-consuming and requires significant efforts from the QA team.

Regression Testing and Re-testing

People often mistakenly think of the term “Re-testing” as a shortened form of “Regression Testing” but you must know that these are two completely different things. So, let us put light on the facts that can help you differentiate between these two widely used forms of testing.

As the name suggests, “Re-testing” means repeating a test for some reason. The most common scenarios when it is performed are when you have newly fixed the source code or when a test case fails in the final execution and as a result, you have to run the test case again.

On the other hand, regression testing means rerunning the new or obsolete test cases to ensure that the new changes in the code have not affected the existing code. While re-testing means repeating the previously executed test cases only, regression testing may have new test cases along with the old ones.

Re-testing offers an amazing error verification feature that is not present in regression testing. However, automating the regression tests and using PreFlight to especially automate any kind of test without any involvement of coding help you achieve the highest level of your testing capabilities and the probability of side-effects due to code changes gets significantly reduced.

Important Challenges In Regression Testing

Being a very crucial part of your entire software testing suite, the path to achieving smooth execution of regression tests is not so simple. You have to successfully deal with the following challenges to smoothly proceed with regression tests.

  • The condition to perform regression tests is any change in the existing codebase and to keep the modern applications up-to-date, you have to keep making changes. That’s why as you proceed with successful regression test runs, the test suite becomes larger. Hence, if you want to keep the business profitable with a proper budget, time, and effort constraints, the complete regression test suite cannot be executed.
  • You have to get a solution for the first challenge and that is minimizing the test suite but for that, another challenge appears because it is almost impossible to achieve good test coverage while the test suite is getting minimized.
  • It is a significantly huge challenge to determine how frequently regression tests should occur such as after every modification to the codebase or after every bug fix or after every build update, etc.

Application of Regression Testing In Modern Agile System

You are certainly aware of the immense popularity and advantages of Agile methodologies. Using them makes you experience awesome benefits like faster time-to-market, a shorter & stable CI/CD pipeline, the capability to provide effective customer support, ROI, easier product improvements, etc. But, our point of concern is that larger test suites make it harder to keep a good balance between the sprint development system and iterative testing measures. And, you have to avoid conflicts in the CI/CD pipeline to grow your business.

However, it is a great step to implement agile approaches to regression testing as you can avoid future reworks by keeping the existing and modified functionalities aligned. It is really a great booster for your business’s growth.

The prime objective of regression testing is to ensure that the new changes and addition to the codebase do not hamper the existing functionalities. It exempts the developers from worrying about the existing functionalities and they can focus on developing new amazing features. Hence, the effective application of agile methodologies in regression testing can help the team identify the unexpected or hidden risks faster and let them respond quickly.

Advantages

The world is brainstorming a lot to achieve the best results from regression tests so that the testing team gets to focus more on improving the overall quality assurance process. Hence, let’s take a look at what advantages you can experience from your effective regression testing strategy.

  • The advanced regression testing techniques help you easily ensure that any new functionality or recent changes do not hamper your existing codebase.
  • An efficient regression test plan with reusable test cases can do wonders in testing the user interface and functionalities of any web application or software application.
  • Using automated regression testing tools like Selenium or its more efficient alternative PreFlight for the regression test executions enables you to easily handle dependencies and efficiently run complex test cases.
  • Proper test case prioritization and strategic handling of test data make sure that the test scripts are smoothly running and there is little or no chance of reappearing of the bugs.
  • An advanced test automation tool like PreFlight provides you with the flexibility to go on with a remarkable regression testing process in cross-platform environments like different operating systems (e.g. Windows, macOS, Linux, etc.), different programming languages (e.g. Java, Python, etc.), and many more.

Disadvantages

There are always some negative aspects or disadvantages of everything based on different perspectives. Here we are discussing the common disadvantages of regression testing.

  • Even a small change in the code can cause a massive difference in the user experience. Hence, you need to run regression test cases (mostly unit regression testing) for numerous changes being made to the codebase.
  • If for some reason, you do not use automation in running the regression suite, you may remain stuck in a forever loop of running frequent tests like integration tests, API tests, etc.

However, using a renowned test automation tool like PreFlight will make you feel like there doesn’t exist any issue with regression tests regardless of how complex or time consuming they used to be. And, for that, you just need to start with booking a demo.

Conclusion

You clearly got the idea of how important regression testing is. If you want to get rid of the worries about how the new changes to your codebase will affect the existing functionalities, you must focus on efficiently performing rigorous regression tests. That way, you can focus more on developing new features and improving the level of your business. You also got the idea that the only way to efficiently perform regression tests is by using an effective automated regression testing tool along with efficient strategies. Hence, you must choose a truly effective test automation tool like PreFlight to fulfill all your needs.

Our simple and highly effective browser extension can solve all your testing needs without involving a single line of coding work. It offers you awesome features like using custom variables, the ability to add custom JavaScript code, an efficient dashboard to access the features, and many more. You can get to know about all the features in detail in the article “10 Amazing Software Testing Benefits From PreFlight In 2022”.

A new no-code testing experience is waiting for you just after you make the small move of signing up. Our website is always available for you to get more information. And, if you get enthusiastic about tech articles, do remember to visit our blog page.