What is Regression Testing? Definition, Tools, Methods, and Example

Regression Testing : As technologies evolve and competition in the software market grows vigorously, business enterprises are understanding the need to deliver the perfect product is needed now more than ever. This is what makes the QA Process very important.

Software Testing can be a long and tedious process because it involves running several types of tests. Among the various testing types, Regression Testing is a rather important one.

What is Regression Testing?

Regression Testing can be defined as a series of tests that are carried out to confirm if a recent program or code change has not impacted the existing features of a Software Solution.

Regression Testing is a complete or partial selection of previously implemented test cases that are executed again to ensure existing functionalities work fine. This process is carried out to make sure that new code changes must not have side effects on the existing features.

Why is Regression Testing Needed?

Regression Testing is needed whenever there is a requirement to change the code and to test whether the modified code affects the other parts of the application.

It is also needed when a new feature is added to a Software Application, for defect fixing, and performance issue fixing.

How to Perform Regression Testing?

To carry out the Regression Testing Process, testers need to check the code and identify the bugs. After the bugs are identified, they need to make the required changes to fix them.

After this, Regression Testing is carried out by selecting relevant Test Cases from the test suite that include both modified and affected parts of the code. Software maintenance is a process that includes enhancements, error corrections, feature optimizations, and deleting existing features.

Some of the modifications may cause the system to work incorrectly. Thus, regression testing becomes vastly necessary.

Regression Testing can be seamlessly conducted by using the following techniques:

Retest All:

This is one of the techniques for regression testing in which all the tests in the existing test bucket or suite must be re-executed. It can be very expensive as it requires a significant amount of time and resources.

Regression Test Selection:

Regression Test selection is a method where a few selected test cases from the test suite are executed to check if the modified code affects the Software Application or not.

Test cases are widely categorized into two parts. The first part consists of reusable test cases that can be used in further regression cycles and the second part is obsolete test cases that cannot be used in succeeding cycles.

Prioritization of Test Cases:   

Prioritizing the test cases depends on business impact and also on critically and frequently used functionalities. The selection of Test Cases based on priority can greatly reduce the Regression Test suite.

How to Select Test Cases for Regression Testing?

According to statistics collected from Leading Software Testing Companies, a high percentage of bugs reported by customers were because of last-minute bug fixes creating side effects. Therefore, selecting the test cases for Regression Testing is can be very complex sometimes.

Regression Testing can be effectively carried out by selecting the following types of test cases:

• Test cases that have multiple and frequent defects.
• Functionalities that is always visible to the users.
• Test cases that can verify the core features of the product.
• Test cases of functionalities that have undergone more changes recently.
• All integration test cases in the suite.
• The complex test cases in the suite.
• Boundary value test cases in the suite.
• Samples of successful test cases.
• Samples of failed test cases.

Regression Testing Tools:

When a Software App goes through frequent changes, Regression Testing Costs can escalate rapidly. In such cases, manual execution of Test Cases increases test execution time along with costs.

The ideal solution to this conundrum is the Automation of Regression Test Cases. The extent of automation could be detrimental to the various test cases that remain re-usable for frequent regression cycles.

Here are a few important tools used for both functional and Regression Testing in software engineering:

Selenium: Selenium is an open-source tool used for Automating Web Applications. It is used for browser-based regression testing.

Quick Test Professional: HP Quick Test Professional is an Automated Software Testing tool designed to automate functional and Regression Test Cases. This tool uses the VBScript language for automation. QTP is a data-driven, keyword-based tool that can make regression easier.

Rational Functional Tester: Rational Functional Tester is a Java tool developed by IBM and is used to automate the Test Cases of Software Applications. This is primarily used for Automating Regression Test Cases and it also integrates with rational test managers.

Challenges in Regression Testing:

Here are some of the major challenges QA Teams might face during regression testing:

• With frequent regression runs, test suites can become fairly large. And because of time and budget constraints, the entire regression test suite cannot be implemented.
• Minimizing the test suite while trying to achieve maximum test coverage.
• Determining the frequency of regression tests after every modification or every feature update or after a bunch of error fixes is a major challenge.

Regression Testing and Configuration Management:

Configuration management while performing Regression Testing becomes imperative in agile environments where a code is being continuously modified. To make sure Regression Tests are effective, QA teams need to observe the following:

• If the code being tested for regression is under a configuration management tool.
• If any changes are allowed in the code during the regression test phase because regression test code must be kept immune to developer changes.
• If the database used for regression testing is isolated because no database changes must be allowed during regression.

Advantages of Regression Testing:

Regression Testing is highly necessary for the QA process and carries several advantages. Here are some of the major benefits:

• Regression ultimately improves the quality of the product.
• It makes sure that any bug fix or enhancement that is carried out does not impact the existing functionality of the product.
• Automation tools can be used for this testing process.
• It ensures issues that are already fixed do not occur again in the future.

Regression of UI:

It is not an easy task to perform a UI Regression Test particularly when the structure is modified. The Test Cases written on an old UI could either become obsolete or demand modification.

Running Regression Tests repeatedly implies that the old UI test cases are modified according to the new UI. However, this task can become highly complex if the desired application has a large set of UI test cases.

What is the Difference between Regression and Re-testing?

Re-testing is done for the Test Cases that fail during execution and the bug or bugs found here would be fixed. Regression testing is not limited to bug fixing as it covers other Test Cases that ensure that bug fixes have not impacted any other functionality of the product.

Conclusion:

Regression Testing allows business organizations to save both time and resources and also deliver defect-free Software Applications to the market. At Sapizon Technologies, we are one of the Best Software Testing Companies, offering Top Rated Regression Testing Services to clients across various industries.

We have completed multiple QA projects with our experienced Software Testing Team. Our company is solely focused on client satisfaction through the implementation of robust testing strategies.