Comprehensive Guide to Regression Software Testing

What is Regression Software Testing and why is it important in software development? Do you know how to perform regression testing effectively and optimally? This article will comprehensively explore Regression Software Testing to help you master this method.

What is Regression Software Testing?

Regression Software Testing is a software testing method used to ensure that old functions of software still function correctly after any changes, including code updates, and feature additions. new or bug fixed. Regression testing aims to verify that recent changes have not caused any problems with existing software.

Types of Regression Testing

Regression Software Testing has many different types, each with its own goals and methods. Here are the main types:

⦁        Corrective Regression Testing

Corrective Regression Testing is performed when there are no major changes in the software source code. The goal of this method is to ensure that the software continues to function without errors after minor updates or bug fixes. This is a quick and inexpensive way to test, often applied when there are only small changes or simple bug fixes.

⦁        Progressive Regression Testing

Progressive Regression Testing is applied when there are changes or new features added to the software. The goal is to ensure that new features do not affect the existing features of the software.

⦁        Retest-All Regression Testing

Retest-All Regression Testing requires retesting the entire system after each change. Although this method ensures the highest test coverage and detects any potential errors, it is very time and resource-consuming. This method is often applied in mission-critical projects where any errors after updates are not tolerated.

⦁        Selective Regression Testing

Selective Regression Testing focuses on testing those parts of the source code that are directly related to changes. In this way, this method saves more time and resources than Retest-All. It identifies and tests affected areas, helping to ensure that changes do not cause errors in other parts of the system.

⦁        Partial Regression Testing

Partial Regression Testing tests modules or parts of the software that may be affected by changes. The goal is to test the compatibility of new modules with old modules.

⦁        Unit Regression Testing

Unit Regression Testing focuses on testing each small unit of software after a change. These are usually individual functions, modules or components. This method is implemented during the development phase to ensure that the units function properly and do not introduce new errors after minor updates.

⦁        Complete Regression Testing

Complete Regression Testing combines all the above methods to ensure the entire system is thoroughly tested. This is the most resource-intensive method but ensures the highest reliability.

Regression Testing Techniques

There are various techniques to perform Regression Software Testing. Here are the most common techniques:

Retest All

Retest All is a technique for retesting the entire software system. Although it ensures that all functionalities are retested, this technique is expensive and time-consuming. It is often used when there are major changes in the system or when product quality is a top priority.

Regression Test Selection

Regression Test Selection focuses on selecting the necessary test cases for testing. This technique divides test cases into two groups: reusable test cases and obsolete test cases. Reusable test cases are test cases that can be reused while obsolete test cases are test cases that are no longer relevant due to changes in the software.

Test Case Prioritization

Test Case Prioritization is a technique of prioritizing test cases according to importance or risk. Test cases that are important or have the potential to cause serious errors will be performed first. This technique helps optimize the testing process and detect errors earlier.

Hybrid Technique

Hybrid Technique combines many different techniques to achieve optimal results. For example, it is possible to combine Regression Test Selection and Test Case Prioritization to both select and prioritize test cases that need to be tested.

Automated Regression Testing

Automated Regression Testing uses automated tools to perform testing. This saves time and increases efficiency, especially when testing needs to be repeated many times. Automation also helps reduce human errors and ensure consistency in the testing process.

Tools for Regression Software Testing

There are many different tools to support Regression Software Testing, from automated tools to manual tools. 

The Software Testing Market was valued at USD 51.8 billion in 2023 and is projected to grow at a CAGR of over 7% from 2024 to 2032, fueled by the rise in product launches and innovations from major companies.Here are some popular tool groups:

Automated Regression Testing Tools

Automated testing tools help reduce the effort and time required for the testing process. They are capable of executing repetitive test cases quickly and accurately. Some popular tools in this group include:

• Selenium
• QTP (QuickTest Professional)
• TestComplete
• Ranorex
• Appium

Manual Regression Testing Tools

Manual testing tools assist testers in performing manual testing. Although not as effective as automated testing in repeating test cases, they are useful in cases where thorough and detailed testing is required. Some popular tools in this group include:

• TestRail
• Zephyr
• TestLink
• qTest

FAQs About Regression Software Testing

What is the purpose of regression testing?

Regression testing ensures that existing software features still function correctly after changes are made.

How is regression testing different from retesting?

Retesting retests fixed errors, while regression testing tests the entire system to detect new errors arising from changes.

What are the best tools for regression testing?

The best tools for regression testing include Selenium, QTP, TestComplete, Ranorex, and Appium.

How often should regression testing be performed?

Regression testing should be performed every time there is a significant change or new update in the software.

Can regression testing be automated?

Yes, regression testing can be automated to increase efficiency and minimize human errors.