What is regression testing and what makes it essential for software testing?

Re-testing: This testing is conducted for specific scenarios that failed during the initial testing phase. When developers fix the bugs identified earlier, we perform re-testing to verify whether those specific bugs have been successfully resolved. Regression Testing: When new features are developed and integrated into an existing module, it's crucial to ensure that these additions do not affect the existing functionality. We need to verify that the new features do not impact the main functionality of the system. In such situations, we perform regression testing to ensure that the previous modules continue to function as expected.

Regression testing checks that when new changes are made and pushed into existing changes,these additions do not affect the existing functionality. Retesting focuses on checking scenario specific test cases that were critical, blocker or a bug. After fixing the bug/small changes, retesting confirms that issue has been resolved.

Regression testing checks if recent updates or changes have caused any new issues in parts of the software that were working before. It looks at many areas to make sure everything still works well after changes. Retesting focuses on checking specific test cases that failed earlier because of a bug. After fixing the bug, retesting confirms that the problem is gone.

Regression testing is a software testing type that ensures code changes(like new features/bug fixes) don't break existing functionality. Involves rerunning previously created test cases to detect any unintended side effects and maintain stability. - As software evolves with new features and bug fixes, there's a risk of regressions. Helps to ensure that existing functionality remains stable after code changes. - Helps identify defects early in the development phase, reducing potential costly issues reaching production. - Helps maintain overall software quality by preventing the introduction of new defects while enhancing/fixing existing features. - Provides confidence that the changes made to the software don't break existing functionality.

egression testing is key to ensuring software systems remain up-to-date and fully functional. There are four common types: Unit Regression Testing: Focuses on individual components, usually handled by developers using automated tools. Integration Regression Testing: Tests how different components interact, performed by testers via manual or automated methods. Functional Regression Testing: Checks if functional requirements work as expected, using test cases or scenarios. Non-functional Regression Testing: Tests performance, security, usability, etc., often with specialized tools.

Sometimes testers ignore the importance of regression testing especially when there is a small fix. Just make an impact list of different modules. Whenever there is a small change and the tester is running out of time, then for the time being you can just perform regression on the listed impact areas. However, this technique is not impactful for enterprise products and the products having a large number of dependencies.

Identify the Change: Understand what parts of the code or system were updated, fixed, or modified. This helps in deciding the scope of regression testing. Select Test Cases: Choose relevant test cases from previous test suites, focusing on areas that may be affected by the changes. Include both critical and frequently used features. Prioritize Test Cases: Prioritize high-impact and high-risk test cases that are most likely to be affected by changes. Automate Where Possible: Use automated testing tools to run repeated regression tests efficiently. Manual testing can be used for complex scenarios. Analyze Results: Compare the new test results with previous ones to spot any new issues. Fix and retest as needed.

In my experience, one of the main challenges of regression testing is maintaining an up-to-date and relevant set of test cases. As software evolves, the regression tests must evolve as well otherwise, they can become obsolete or miss critical new functionality. To mitigate such issues, one best practice is to continuously review and update the regression test suite. Another best practice is to prioritize test cases. Not all tests are equal. some cover critical paths, while others might be for less significant features. By prioritizing tests, one can ensure that the most important aspects of the application are always tested first, which optimizes the time and resources spent on regression testing.

Challenges of Regression Testing: It can be time-consuming, especially for large systems. Maintaining a growing test suite is difficult, as some test cases may become outdated. Automation isn't always easy, and maintaining scripts can be complex. Limited resources like time, budget, or tools may affect test quality. Identifying all affected areas after changes is challenging and can lead to missed issues. Best Practices: Automate repetitive tests, focus on areas likely to be impacted, and maintain an updated test suite. Prioritize critical features and schedule regular regression runs to ensure software stability.

One of the best things is to make a regression suite of your system. This way there is less chance that a tester could miss a module to perform regression for. Also, divide the areas that are similar (inside a module) that are stable for a long time. And perform regression testing on it turn-by-turn. For example, uploading images is happening on multiple pages inside the system. If one of them is working, the other should be. Because at the backend the same function is calling.

Agree! I have found that early smoke testing, prioritizing test cases and automation can help with the issue of an ever expanding regression test suite.

Regression testing is essential in software development, ensuring that changes do not break existing functionality. It can be said to be the guardian of quality, preserving the integrity of the code. Embracing regression testing helps inspire confidence in your product and drive innovation forward.

When considering regression testing, several other factors are important to keep in mind to ensure its effectiveness and efficiency: 1. Test Automation: Automated regression tests can be more reliable and faster than manual testing, especially for large and complex systems. They also allow for frequent execution at a lower cost over time. 2. Test Maintenance: Regularly maintaining and updating the test cases to reflect changes in the application to avoid test rot, where tests no longer reflect the current state of the software. 3. Environment and Data: Ensuring that the testing environment closely mirrors the production environment and that tests use a diverse set of data to simulate different scenarios and edge cases.

Regression testing is a sensitive step and being a tester we can't ignore this. The ultimate success of users and stakeholders solely depends on what product they receive at the end. Think from the user's perspective and plan this accordingly.

Regression testing is a crucial aspect of software testing that verifies whether recent code changes have affected existing functionalities adversely. It involves re-executing select test cases to ensure that modifications or additions to the codebase haven't introduced new bugs or caused previously fixed issues to resurface. By systematically retesting software after alterations, regression testing helps maintain the integrity and stability of the application, ensuring that it continues to perform as expected across iterations and updates. This practice is essential for detecting and preventing unintended consequences of code modifications, thereby safeguarding the quality and reliability of the software product.