Your Guide to Regression Testing in Software Development
Regression Testing is a type of software testing where previously tested functionalities are re-tested to verify that recent code modifications do not affect existing features.
Performance enhancements, bug fixes and new updates require alterations to the code base of the application. Hence, unforeseen issues might appear. Therefore, identifying and fixing any regressions or bugs is crucial to maintaining the overall software quality.
In this article, we’ll cover everything you need to know about regression testing.
| Table of contents |
|---|
| • When should Regression Testing be performed? |
| • Real-life example for regression testing |
| • How is Regression Testing implemented? |
| • Types of Regression Testing |
| • Benefits of Regression Testing |
| • What is the role of Quality Professionals? |
| • Frequently asked questions |
When should Regression Testing be performed?
Below are some key scenarios in which regression testing is needed:
- Adding new features:
Regression testing is used to validate that pre-existing features continue to operate seamlessly, and risks of a downtime are mitigated. - Bug fixes:
Regression testing is used to verify that code adjustments to fix bugs do not affect other components in the application.
- Optimizing the code:
Regression testing guarantees that optimizing the code will enhance the application without adversely impacting other functionalities.
Example – Amazon Website Regression Testing
Take Amazon.com as an example, every day, Amazon’s e-commerce platform processes millions of transactions. Thus, seamless performance is significant to the company’s operations. Consider this scenario: a new feature must be added to the homepage such as a “Prime Day” exclusive offer. Before adding this section, it is important to make sure that such an addition does not disrupt any of the existing functionalities like search, cart checkout, or payment processing. To verify this, a Regression Test suite would be executed to confirm that all other components continue performing as expected.
For instance, if this test fails and reveals that the “Checkout” button is unresponsive or leads to a broken link, it would be flagged as a bug. Developers would then prioritize fixing this issue to prevent monetary lossanda bad customer experience which would affect the brand.
By using regression testing, you can confidently implement changes to your software while maintaining the user experience across various functionalities.
How is Regression Testing Implemented?
The procedure followed to implement Regression Testing is similar toother testing processes. Every time the application undergoes code adjustments; the following steps are taken:
- Initially, unit-level regression tests are executed to validate the modified code alongside any other tests written to cover new or changed functionality.
- Then, the new code is merged and integrated to create a new build of the application under test (AUT)
- Next, smoke tests are executed for assurance that the build is good before any additional testing is performed.
- Once the build is declared good, integration tests are performed to verify the interaction between units of the application with each other and with-end services like databases.
- After that, depending on the size and scope of the released code, either a partial or a full regression is scheduled.
- Defects are then reported back to the development team.
The Image below depicts how Regression testing is performed
Types of Regression Testing
There are several types of regression testing, each one serving a specific purpose, here are some common types:
- Corrective Regression Testing
This type exclusively focuses on verifying that specific fixes made to the application have been successfully resolved without introducing problems.
- Retest-All Regression Testing
This type involves re-running all the test cases in the test suite to ensure that the entire application is still functioning correctly.
- Selective Regression Testing
As the name indicates, this type of test is only a subset of the test cases that are most likely to be affected by the recent changes, reducing the effort and cost of testing.
- Progressive Regression Testing
This type is used when there is an update on the software specifications.
- Complete Regression Testing
This type is performed when multiple changes have been made to the software, it involves testing the entire application to ensure overall stability.
- Unit Regression Testing
Focuses on testing individual units or components of the software to ensure no new bugs are introduced at the unit level.
Benefits of Regression Testing
Regression Testing ensures stability and reliability, offering the following key advantages:
- Preserving Functionality: Protecting existing features from unintended outcomes of code changes.
- Boosting Confidence in New Releases: Providing assurance for successful new releases and updates.
- Enhancing Quality: Detecting and resolving defects early.
- Improving Efficiency: Implementing automation which accelerates testing, minimizes errors, and lowers development effort.
- Ensuring User Satisfaction: Delivering a consistent and reliable user experience.
By incorporating regression testing into the development process, companies can guarantee that their software and applications remain robust and reliable, even as it evolves.
What is the role of Quality Professionals (Q-Pros)?
Being familiar with the latest tools we never let you struggle with software errors. Our regression testing experts’ techniques and tools easily find the effects of modified code on the functionality of the software and help you to get a bug-free application in the changing operating environment.
Frequently Asked Questions
What is automated regression testing?
Automated regression testing is a software testing technique that uses specialized tools and frameworks to execute regression test cases automatically, providing faster feedback and increased efficiency.
What is the difference between regression testing and integration testing?
While Regression Testing is performed after changes are made to the codes, integration testing is done after unit testing and before system testing. Both types are crucial to delivering high-quality software.
How to execute regression testing?
Regression testing can be executed with the following steps:
- Selecting test cases.
- Estimating time to execution.
- Identifying cases for automation.
- Setting priorities.
- Executing test cases.
When to execute regression testing?
Regression testing is recommended to be executed by the end of every sprint.