Skip to main content
BlogsSoftware Testing guidance

A Deep Dive into What is Regression Testing in Software Testing?

By July 8, 2020September 20th, 2023No Comments8 min read
A Deep Dive into What is Regression Testing? Types and How to do it?

A regression testing in software testing verify modifications to a software program do not create new errors, or break existing functionality. Different types of regression testing is used to make sure your product or service continues functioning as it should. This can be done by ensuring all the features work together seamlessly and that there are no bugs in them which could lead an end-user experience down a path of frustration, resulting in decreased conversions for your business’s bottom line!

This Regression Testing Guide covers the essential aspects of regression testing, including what it is, the various types of regression testing, how to perform it, and when to consider using it. By reading this guide, you will gain a comprehensive understanding of the concept of regression testing, its significance in software testing

What is Regression Testing in Software Testing?

Regression testing is a type of software testing that seeks to uncover new bugs in existing functionality. This is done by re-running previously completed tests and comparing the results to the expected outcomes. If a discrepancy is found, then there is a potential regression bug.

Regression testing is an important part of the software development process as it helps to ensure that new code changes have not introduced new bugs into the existing code base. It is also a valuable tool for debugging, as it can help to pinpoint where exactly a bug has been introduced.

General changes in the code make certain changes;

  • Dependencies
  • System malfunctions
  • Arising defects

The regression test is generally the final test that the application goes through amongst the myriad of tests that are conducted throughout the maintenance of the software development lifecycle.

Why Regression Testing is Required?

Regression testing is a type of testing that is conducted to verify that changes made to a system or software have not introduced new bugs or errors. This type of testing is typically performed after any major changes have been made to the system in order to ensure that the system still functions as expected.

There are many reasons why regression testing is important. First, it helps to ensure the stability of the system. If new changes have introduced new bugs, then regression testing can help to identify and fix those bugs before the system is released to users.

Second, regression testing can help to ensure that the changes made have not caused any unexpected side effects. Finally, regression testing can also help to verify that the system still meets all of the requirements that it is supposed to meet.

Regression testing can be a time-consuming and expensive process, but it is absolutely essential in order to ensure the quality of a system or software. Without regression testing, it would be very difficult to confidently release new changes to a system, since there would be no way to know for sure that those changes would not cause new problems.

 How To Do Regression Testing?

Regression testing is a process of retesting a system or application after making changes to it. The purpose of regression testing is to ensure that the changes made have not introduced new bugs or faults into the system. Regression testing can be done manually or automated. Let’s see how to perform regression testing.

-> Automated Regression Testing are typically done using a tool such as a test recorder, which can record the user interactions with the system under test and generate a script that can be played back to reproduce the same steps. Automated regression tests can be run frequently and quickly, providing faster feedback on the state of the system.

-> Manual Regression Testing is typically done by running through a test suite or set of test cases that cover the functionality of the system under test. This can be time-consuming and error-prone, so it is often automated to some extent, for example by using a test management tool to manage the test suite and track progress.

Regression testing should be done whenever changes are made to the system, including new features, bug fixes, and performance improvements. It is an important part of the software development process and can help to ensure that changes made to a system do not introduce new bugs.

Steps to start with regression testing;

  1. By exploring different functionalities of application Design your regression Test scenarios or regression suite.
  2. Define your unique approach to words the regression testing.
  3. Figure out your Test Cases.
  4. Select your regression Testing tool.
  5. Try to run regression testing with automation.

What are the Different Types of Regression Testing?

Regression Testing is not a one-size-fits-all approach, as there are different types of regression testing that can be used depending on the specific requirements of the application and the changes made. Let’s explore one by one…

  • Unit Regression Testing

This is one of the most pivotal parts of unit testing. This is mostly focused on the coding unit and this test makes sure that all the resultant dependencies are blocked out during the test. This test specifically focuses on various factors such as recurring defects along with the criticality of certain features in consideration. The main aim of this test is to deliver a useful unit of code that enhances and adds value to the totality of the application.

  • Corrective Regression Testing

This type of regression testing is in utilisation when there are absolutely no pertaining changes introduced in the specification of the product. Moreover, there is no need to build any new test cases as the already existing test cases can be reused to test and ultimately derive the desired result.

  • Selective Regression Testing

This regression test is used to analyse the impact that the newly added piece of code on the existing application software. This regression test makes sure to use a subset of the already existing test case. This further reduces the cost involved in retesting along with the efforts being saved for constructing a new test case from scratch.

  • Reset All Test Case

This is a rather tedious form of regression testing as there is a lot of time that gets wasted. This further involves testing all the existing aspects of any particular product along with reusing all the test cases even to the places or sections where there have been absolutely no test cases made. This type of test is totally not advisable when there is just a minor change that has been infused in the existing product.

  • Progressive Regression Testing

This regression test works wonders when there are minor changes that are done in the program specifications along with new test cases that are being designed.

Conducting this form of testing helps in making sure that no previous features have been compromised in the new version.

  • Complete Regression Testing

This is the best regression testing to be used in case of major changes cropping up in your test code. This is specifically used when there is a major change in the root code of the software. This is helpful in combating unexpected issues and in the end test before handing off the application to the user.

  • Partial Regression Testing

As the name suggests partial regression testing is done as and when new codes are added to the already existing piece of code. The core idea behind this test is to ensure that the system is performing in the same way as it was earlier.

When To Do Regression Testing?

As a general rule, QA regression testing should be carried out any time there is a change to the software. This could be a code change, configuration change or even just an upgrade to a third-party component. By re-running your tests after making changes, you can be confident that the software still behaves as expected and has not been adversely affected by the changes.

There are some specific situations where regression testing is particularly important:

Release Testing: Before releasing a new version of the software, it is essential to regression test to ensure that all the existing functionality still works as expected and that there are no new bugs introduced.

-Bug Fixing: After fixing a bug, it is good practice to regression test the affected areas of the software to make sure that the fix has not introduced any new problems.

-Compatibility Testing: When testing software compatibility with different browsers, operating systems or hardware platforms, regression testing is essential to ensure that existing functionality still works as expected.

Regression Testing Examples

Suppose you are working on a software application that calculates and displays the total price of a customer’s order based on the selected items and their respective prices. You have previously tested the application and found that the price calculation and display functionality is working correctly.

Now, the development team has made changes to the application to improve its performance and fix some bugs. Before releasing the updated application to the users, you need to perform regression testing to ensure that the price calculation and display functionality still works correctly.

To perform regression testing, you would follow these steps:

  1. Identify the test cases related to the price calculation and display functionality.
  2. Execute these test cases on the updated application to verify that the functionality still works correctly.
  3. Compare the results of the test cases executed on the updated application with the results of the same test cases executed on the previous version of the application.
  4. If there are any differences in the results, investigate the cause and report any defects to the development team for fixing.

In this example ensures that the changes made to the application have not introduced any new defects or caused any previously fixed defects to reappear.

Bottom line;

Software regression testing is the core of improving your application’s ultimate quality and ensuring that you’re experiencing a satisfying user experience. The right tools and types of regression testing can also help identify potential defects early on which will lead to more fruitful pipeline steps in prevention or correction measures – meaning less time wasted fixing errors later down line!

At Testrig, we employ a structured Regression Testing methodology that ensures seamless integration of new features or enhancements into your application, without any unexpected disruptions or cost overruns. Our Software Regression Testing Services is designed to safeguard the existing quality and functionality of your software, assuring that your enhancements deliver the intended results.

Reach out to us today to leverage our expertise in software regression testing and ensure the smooth implementation of your software improvements

Leave a Reply