When does regression occur in a software product? Whenever there is any change in the application code. Application or software development is not complete without adding new features or changing its existing code.
Occasionally, major (or even minor) application changes can impact another functionality unexpectedly. This is a regression. What then is regression testing? This testing ensures that any code change does not impact the product functionality unexpectedly. The question is about when the best time is to perform it.
Regression testing is necessary after any feature (or application) enhancement, bug fix, or configuration changes. For example, when developers add a new widget to an application. As more regressions are found in software products, companies are moving towards test automation to perform regression tests.
Here is what product companies need to know about regression testing.
What is regression testing?
Regression testing is a form of software testing that checks if any code change or a new feature has introduced any new software regressions. This testing approach can confirm if the product is working as before with the new features and bug fixes.
Primarily, there are three types of software regressions, namely:
- Local regressions: when a code change in a product component introduces a new defect in the same component.
- Remote regressions: when a code change (in one component) creates a new bug or defect in another application component. Typically, this component did not have any issues before the code modification.
- Unmasked regressions: this is the “hardest” among all regressions, where a code change “exposes” an existing bug which did not previously impact the application.
Regression testing is not the same as retesting. Retesting is all about testing a particular product feature or enhancement to check if it is performing as expected. In regression testing, existing test cases are executed again to verify the impact of the code change.
When to perform regression testing?
Companies must ideally perform regression testing every time their application codebase is modified. According to most testing experts, it must have a fixed testing schedule. Even partial testing can highlight potential regression-related issues in the application. With frequent testing, product teams can detect and fix minor issues as soon as they are found.
Here are a few instances or scenarios when regression testing must be performed:
When a new feature is introduced in the product
Regression testing is necessary whenever a new feature or enhancement is added to the product. Application developers find it challenging to follow code-related dependencies when working on a new feature. Hence, regressions can arise because of incompatibility issues with the existing codebase.
In this instance, regression testing checks if the new feature is working as expected. Additionally, developers can save time and effort by detecting and solving minor bugs in the initial phase. This prevents major complications and bugs in the later development phase.
After fixing a software bug
After a bug fix, performing regression testing can ensure that the fix does not change any other functionality. Sometimes, a single bug fix can also cause additional regression bugs. For a regression testing example, a bug fix in the login page can sometimes cause errors in the registration page.
Besides this, regression testing is necessary after every debugging session. Essentially, developers perform debugging after any major and minor change to the codebase. In this instance, regression testing helps to check if the bug fix did not create additional issues.
When integrating with an external system
Modern applications can integrate smoothly with third-party applications or external systems. However, integration between two separate systems is not straightforward and has its share of challenges. When developers make changes in the integration code, it can create bugs and errors.
Regression testing is necessary whenever the product integrates with a new external application. This ensures a smooth integration that is free of all bugs and defects.
Following a major business change
Regression testing must be mandatory whenever the organization undergoes a major shift in its business strategy. This change can have a profound impact on product functionality. Application developers often need to redesign the existing product or even remove existing features. These changes can inadvertently “damage” other functionalities, which can cause regressions.
For instance, regression testing can detect problems following a major website revamp or a mobile app (with a fresh design).
How to perform software regression testing
The emergence of QA automation is facilitating application development companies to improve software testing quality. Automation can make regression testing easier to execute. Besides the speed, automated testing can improve product quality.
On the other hand, manual testing deploys the expertise of trained software testers in detecting software bugs. QA engineers can easily perform manual regression testing on smaller and simpler software products.
However, as software products gain more complexity and functionality, manual testing becomes more time-consuming and inefficient. This is because advanced applications increase the scope of regression testing. In this scenario, automated testing offers many benefits, including the ability to:
- Increase the frequency of running the regression test cases.
- Redirect the “human” testing team to higher tasks that demand creativity and critical thinking.
- Provide a cost-effective mode of testing application code.
Why ACCELQ for regression testing?
Effectively, regression testing enables companies to achieve continuous integration and development (CI/CD). ACCELQ, a leader in “continuous testing” as recognized by Forrester Wave, enables codeless automation for a range of software products including web applications, mobile apps, and API services.
Based on Artificial Intelligence (AI), ACCELQ provides a unified platform for full-stack continuous development. Here is a blog that highlights the use of the ACCELQ API-based regression automation suite.
You can leverage the benefits of automation in your regression testing approach. We are here to help you. Request for a product demo today!