What is Regression Testing? Explained with Test Cases, Tools, and Methods
In the software development lifecycle, testing is often overlooked or not given the same amount of significance as development. However, it is as important or more important than development because a buggy application with various features can cost you money and loss of user base.
In this blog, we’re going to walk you through in detail related to regression testing, its test cases, types, tools, and everything else you need to know. So, let’s get things moving!
What is Regression Testing?
Suppose you’re a software development firm, and the client has assigned you the project to develop an application for image and video editing. With the primary requirements, you create the first build with core features. Once done, you conduct regression testing with 1000 test cases to ensure that the app works correctly. After the app passes the regression test, you send the copy to the client for feedback.
The client is happy with the first build but wants some extra features. So, you develop those features and add them to the existing app. But, with the addition of new codes, you will be required to conduct regression testing again. Hence, you write 100 new test cases and verify the functionality of the app. But along with that, you will have to run the 1000 old test cases already conducted to ensure essential functions haven’t been affected.
Regression Testing Example
Suppose you’re a software development firm, and the client has assigned you the project to develop an application for image and video editing. With the primary requirements, you create the first build with core features. Once done, you conduct regression testing with 1000 test cases to ensure that the app works correctly. After the app passes the regression test, you send the copy to the client for feedback.
Pros and Cons of Regression Testing
Pros
- Ensures that any change in code doesn’t adversely affect other functionality.
- Makes sure that already fixed issues don’t re-occur.
- Serves as a risk mitigation strategy during testing.
- Easy to learn, understand and analyze.
Cons
- Without automation, regression testing can be time-consuming.
- Need to perform for every small change of code.
- A highly repetitive process may affect the agile sprint.
- Requires you to create complex test cases.
Challenges in Regression Testing
- High Upfront Cost: Regression testing is very time-consuming if done manually.
- Testing Approach: Selecting a proper testing approach is crucial to success as far as regression testing goes.
- Enormous Scope and Coverage: The success of regression testing depends on the type of test cases suite you have built.
- Complexity: As you move from the first build to the second and then so on, the number of test cases increases.
How to Conduct Regression Testing?
Generally, there is no fixed pattern for implementing regression testing. However, there are some popular regression testing methods that a QA analyst should keep in mind.
Generally, there is no fixed pattern for implementing regression testing. However, there are some popular regression testing methods that a QA analyst should keep in mind.
Step 1: Regression Test Selection
As the name suggests, here, you select the test cases that require re-testing. You won’t test the entire test suite, and the selection of test cases will depend on the module where there is a change in the source code.
Step 2: Determine the Time for Executing Test Cases
The next step is to estimate the time it will take to execute the selected test cases. Few factors that affect the execution time are test data creation, regression test planning by the QA team, review of all test cases, etc.
Step 3: Identify the Test Cases that can be Automated
In this step, based on the results of exploratory testing, the QA team can decide the test cases that they can automate. Automated test cases are faster than manual testing and allow you to re-use the same script repeatedly. So, divide the test cases into two groups – (i) manual test cases and (ii) automated test cases.
Step 4: Test Cases Prioritization
Here, you gather all the test cases and prioritize them, i.e., high, medium, and low. Based on this evaluation, you will execute the high-priority test cases first, followed by medium and low priority test cases. The priority will depend on the product’s functionality and user involvement.
Step 5: Executing Test Cases
Finally, it’s time to execute all the test cases one by one and test whether the product is working as it should or not. You can opt for manual testing or automation based on the requirement. For automated regression testing, utilizing tools like Selenium, QTP, Watir, etc., allows you to execute the test cases faster.
Regression Testing Methods
There are primarily four most popular regression testing methods:
- Regression Test Selection: Here, you select the test cases that need to be re-tested.
- Test Case Prioritization: Here, you gather all the test cases and prioritize them.
- Retest All: Here, you re-test the entire regression test suite.
- Hybrid: Here, you combine Regression Test Selection and Test Case Prioritization method.
How to Create an Effective Regression Testing Suite?
A regression testing suite is a set of test cases designed to ensure that your software is accurately working as it should after any changes or updates. Below are the five steps to creating an effective regression testing suite.
Step 1: Prioritizing Regression Tests
Step 2: Developing Smoke Test
Step 3: Take Assistance of Manual Testing
Step 4: Test the Integrations
Step 5: Take Performance into Account
Regression Testing Types
- Corrective
- Progressive
- Selective
- Partial
- Complete
- Retest-All
Top Regression Testing Tools
- Selenium
- Katalan Studio
- Watir
- IBM Rational Functional Tester
- Apache JMeter
- AdventNet QEngine
- Subject7
- TimeShiftX
- Cerberus Testing
- Testsigma
Regression Testing Best Practices
Most people believe that retesting and regression testing is the same. However, that is not true; both these terms have a separate meaning.
1. Regression Testing Best Practices
Like keeping up with any technology, you need to stay up-to-date with the latest regression testing suites too. For that purpose, always consider the functional and non-functional requirements. The high-priority and high-value test cases in the suite should always be executed first by the QA team.
2. Knowing Every Change Hands-on
Have regular communication between developers and testers to know the latest upgraded version and be aware of immediate changes. They can plan their testing well in advance to stay on track with the app or product release.
3. Assigning Grade to Test Cases
If you want to succeed with regression testing, you need to assign grades to all your test cases. You should compare and track their business impact on different platforms, and based on those evaluations; you should set high, medium, and low priority to various test scenarios.
4. Understanding the Scope of Testing
Before starting the regression testing process, it’s essential to know its scope. The reason being each testing project can vary in terms of scope, time, and goals. Understanding differences in scope will allow you to plan your regression cycle execution better
5. Automate the Right Test Cases
Automation gives you a competitive advantage only if you utilize it properly. So first, you need to identify which test cases you can automate and those that don’t have a scope of automation. Then, automating suitable test cases will increase your productivity and save precious time.
6. Track RoI
QA teams should always track RoI based on the advanced analytics and reports generated by automation tools. It will help you to witness the on-ground reality and areas that need improvements.
Regression Testing and Agile Methodology
Agile teams should prepare the regression test suite from the initial stages of the product development cycle and then follow that until the final deployment. In agile methodology, you can conduct regression testing in two ways:
- Sprint Level Regression
- End-to-End Regression
Summing Up Things
Organizations could have avoided these fatalities if they had conducted regression testing before updating or adding a new feature. From the above example, you must have realized the importance of regression testing in this day and age.
Regression testing becomes vital if you want to deliver high-quality and robust applications where users could be loyal. Taking those scenarios into consideration, in this article, we have provided you with a comprehensive view of regression testing, its types, tools, methods, and everything else you need to be aware of.
Originally published at Simform: What is Regression Testing? Explained with Test Cases, Tools, and Methods