Many companies and development teams underestimate the importance of regression testing.

If done right, it can improve the quality of your product and user experience and help gain customer trust. In this article, we will take a deeper take on regression testing, its importance, challenges, and how to execute it.

What is regression testing?

Regression testing is a type of application testing to determine if the software still functions after the existing code has been changed or modified. 

It is a crucial step in allowing developers to continuously improve the software without adversely affecting its existing functionality. The goal of regression testing in software development is to uncover issues resulting from any changes that may affect the functioning of the software.

Regression testing vs. Retesting

Many confuse regression testing with retesting, but both differ in multiple factors. Retesting is testing a specific code after it has been changed, whereas Regression testing is testing the functionality of overall software after new changes have been made.

Regression testing is performed after retesting. Retesting is applied to failed test cases, but Regression testing is done on test cases that have passed successfully.

Regression TestingRetesting
Test cases can be automated and can be done manually as well.Test cases are only manually executed.
Verifies the overall functionality of the product after a change.Uncovers bugs after a fix has been done on specific code.
Executed on low priority as compared to retesting.Executed on high priority as compared to regression testing.
It ensures that other sections of the software that are not part of the change remain unaffected. It is performed to identify specific defects.
Test cases can be identified and gathered at an early stage of product development.Test cases can’t be gathered before the testing process.
Table: Regression testing vs. Retesting

Importance of regression testing

regression testing

Regression testing is crucial for checking the complete functionality of software after newly added features, changes, modifications, or integration with new software. It verifies if the software is performing as it is supposed to be before handing it to the user. It helps in improving the user experience and gaining customer faith.

Regression testing can be done manually as well as can be automated. Automated test cases help in reducing time, resources, and money for the overall project. It also helps in reducing the test cases for the next project. With automated regression testing, the team can focus on other areas of software development, thus delivering the product on time.

Regression testing provides stability and seamless continuation of the workflow in agile methodology by testing software within the sprint cycle. It helps detect bugs or errors early in every stage, thus reducing time and money.

Advantages, Disadvantages, and Challenges of Regression Testing

Advantages

  • Regression testing is an important step to improve the quality of the software and user experience as well. 
  • It ensures that any changes done in the source code have not affected the overall functionality of the software.
  •  It saves time and money by helping to deliver a high-quality product faster. Through automated test cases, the cost and time of the overall project are reduced dramatically.

Disadvantages

  • Though regression test cases can be automated, some cases need to be done manually. Manual testing requires a lot of time and human resources.
  • Regression testing is a highly repetitive process, and even a small change needs testing as it can affect the basic functionalities of the software.
  • Complex functionalities mostly need complex test scripts, which can delay the testing execution deadline.

Challenges

Despite all the great benefits regression testing brings, there are some challenges as well: 

Selecting the right tool – For the success of regression testing, it is essential to choose the right tool. Otherwise, it will result in spending time, money, and resources.

Time – Regression testing is repetitive and hence time-consuming. That’s why it becomes a huge challenge to execute and deliver the product before the deadline.

Complexity – Due to its highly repetitive nature, the test cases become increasingly complex as the product goes from the first stage build to the next. It will require testing the old test cases along with new ones all the time.

Regression Testing Use Cases

Regression testing has the following use cases:

  • New functionality is added to the software: Whenever a new code is added to add new functionality, regression testing is done to make sure that it is compatible with the existing code. It then points out any possible issues or bugs in the software.
  • Changes in existing functionality: Sometimes, the existing functionality is changed or modified according to the requirement, then regression testing is done with the same goal to ensure that it has not caused any issue to the software.
  • The software has been fixed after a defect: After finding a defect and fixing it, testing is needed to check if it is now performing well along with other functionalities related to the defect. 
  • Source code optimization: For example, the software takes 5 seconds to load, and with optimization, the loading time has now been reduced to 2 seconds. After making the changes, testers test whether the software’s functionalities have been affected or not.
  • Changes in the environment: For example, the software has updated its database from Oracle to MySQL. In this case, testing is needed to ensure the software performs as before.

How to perform regression testing?

The best time to create a regression testing strategy is at an early stage of software development and then align it with the product until its release. Here are the steps to perform regression testing:

Step 1: Detect and understand changes

Firstly it is vital to get a clear picture of and understand what changes have been made to the software. Detect the changes and modifications done on the source code and identify how it has impacted the component and the software features.

Step 2: Gather test cases required. 

Identify and collect all the test cases needed to execute the testing. Include test cases that verify the proper functioning of the software, which include its home page, login and logout page, etc. Add cases to all the components that are more likely to get errors. In the end, include test cases that are complex. 

Step 3: Determine test cases that can be automated

Automated tests are the best way to perform testing because they are fast, reliable, and can be reused for the next project. But some test cases need to be performed manually, such as GUI event sequences. Identify which cases can be automated and which need to be done manually.

Step 4: Execute test cases in priority order

After building the regression test cases, sometimes teams may find out that all the test suites can not be performed simultaneously. In that case, regression prioritization comes into the picture. Define which test cases should be run on priority based on which component/feature is most critical to the software. Priority should be given to tests that perform testing on core functionalities of software that deliver the most value. 

Step 5: Select tools and perform the testing

Once the first test cases are delivered and the best regression testing tool is selected according to the requirement, it is time to perform the execution. 

Let’s now look at some of the best tools to perform regression testing.

Testsigma

Testsigma is a rapid, cloud-based, and AI-powered testing tool. It uses AI to detect and fix any abnormalities in the existing code.

Features:

  • Cloud-based, Effortless, and scriptless regression testing
  • AI-powered self-healing test automation
  • Create test suites in simple English
  • Multiple test executions can run parallel 
  • Scheduled test execution
  • Test reports and visual/text logs
  • Notifications through email, slack, and Teams

Most importantly, Testsigma helps create tests in simple plain English. It allows thousands of tests to run parallel, resulting in rapid execution of regression testing. Testsigma provides drill-down test reports for easy debugging.

Katalon

Katalon gives full platform support to run on both cloud and on-premise infrastructure. 

Features:

  • Very lightweight and allow test creation on all OSs, devices, and browsers.
  • Beginner-friendly
  • Codeless test creation
  • Seamlessly integrated to agile and CI tools like Bamboo, Azure, Jenkins, and CircleCI.

It is a robust platform that allows test creation on every operating system, device, and browser.

Testrigor

Testrigor creates test cases for testing without any need to code. This is the best testing solution for those who want to spend less time on test maintenance.

Features:

  • Test case creation in plain English.
  • Create custom test scripts easily.
  • Low-maintenance and ultra-stable regression testing solution.
  • Issues are uncovered easily.
  • Execute tests keeping users’ point of view.

This tool executes multiple tests autonomously and from users’ points of view, making it ultra-stable.  

K6

K6 is one of the best open-source testing tools and a great SaaS for software development teams/companies.

Features:

  • Open source and cloud-based testing solution
  • Build test scripts in Javascript
  • Zero maintenance and full platform support
  • Faster test creation using GUI test builder
  • Browser recorder to record user journey and build scripts faster
  • Schedule and automate test scripts 

This tool is specifically designed to be flexible, easy to use, and powerful. It provides a K6 cloud to run and scale tests effortlessly.

Smartbear

Smartbear is a reliable, high-performance, automated testing platform. It focuses on delivering quality testing solutions without compromising on speed or agility.

Features:

  • Automated and data-driven testing
  • AI-powered visual recognition 
  • Automated test reporting from a single interface
  • Effortless defect tracking and analysis
  • Keyword-driven testing framework to separate test steps, objects, actions, and data easily

Smartbear provides automated UI test solutions for all applications.

Putting it all together

A good regression testing strategy saves time, resources, and money and is an important key in delivering high-quality products to customers. Leveraging software testing right from the start of the development cycle helps meet customer expectations efficiently.

Adopting this type of testing in agile ensures that the operations are performed seamlessly at every stage, and the product is delivered on time. Creating a testing strategy and selecting the right tool is essential to the overall success of regression testing.