Errors, bugs, and fallacies are all a part of the software delivery process. It’s the presence of these inefficiencies that ultimately paves the way for an improved release. However, that’s only possible when a sound testing plan is in place, and understandably so.
The term “sound testing plan,” however, fuels a separate discussion around the best testing practices for a particular scenario and application – Should it be a test-driven approach? A load-driven scenario? And what about retesting?
That being the case, perplexity in such discussions usually becomes the front-runner courtesy of presumably synonymous overlapping testing methods. One such confusion bothers the concepts of regression testing and retesting.
For instance, a retest is when you manually re-run a previously performed regression test to see if it still works. In contrast, a regression test ensures that new features or functionality don’t break existing components or functionality. Unfortunately, when running regular regression tests, it’s easy to be lulled into assuming that they are the same thing as retests.
Although both contribute significantly to the entire testing process, their implementation, application, and execution are different. So, let’s make sure we don’t confuse these two terms anymore, shall we?
What is Regression Testing?
Regression testing is the process of analyzing the program code and data files and executing its related tests to ensure that any changes made to the application or software do not break existing features or functionality. It’s an important practice in software testing.
The primary goal of regression testing is to maintain a bug-free environment for users and developers by blocking unwanted regressions when new features are introduced into an application. As such, regression testing should be done periodically even if no bugs were found during earlier stages of development, especially after supplementing any significant new functionality.
SUGGESTED READ -
What is Retesting?
Contrary to regression testing, retesting is done to test whether a particular feature or functionality that has been developed, tested, and released is working as expected. It’s generally carried out after significant modifications to the code or software are made.
When running retests, your goal is to determine whether any known bugs have re-emerged or whether new bugs have appeared.
SUGGESTED READ -
When Is Regression Testing Done?
A variety of cases entail the application of regression testing. This includes after installing a new feature, upgrading or patching, and releasing a new product.
The most common types of regression tests can be summarized as follows:
- Implementation of a new feature – For example, when there has been a refactoring that may have removed some code, which was required but no longer exists – regression testing, in such case, would address the assumption that all the code needed for the new feature will still function properly.
- Updates and patches application – Regression testing can be done before or after installation to ensure that the changes are compatible with the existing software. Likewise, a regression test can be run after deploying a new release to ensure no unintended consequences were associated with the same.
When is Retesting Done?
The most common types of retest cases are summarized as follows
- Retesting is done when there are bugs in the software, problems with the reports, or re-emergence of other issues. A re-test ensures that these issues no longer appear.
- Changes in the business logic – The numbers of a report may have changed, a new field has been added to a database table, or some other notable change has been made that would affect the overall functioning.
Regression vs. Retesting – Overview of the Differences
|Automation||Considering that the testing suite expands with the enhancements, the automated regression testing approach seems viable.||Because the motive is to fix the pre-existing areas, automating the methods seems unnecessary and implausible.|
|Involvement||Regression testing must be a perpetual monitoring process since updates, upgrades, and patches are constantly unearthed to keep up with the dynamic market.||Since retests depend on identifying the bugs in the first place, retesting may or may not be employed in each testing cycle.|
|Types||Corrective, selective, progressive, partial, unit, retest-all.||No types as such; however, the practice to re-test can differ according to the needs.|
|Nature||Since it’s perpetual, regression testing is often termed generic testing.||Since its implementation is specific to the identified defective area, it’s often termed planned testing.|
|Defect Verification||NA||A part of retesting process|
|Applicability||Fixated on passed test cases.||Fixated on failed test cases.|
|Priority||Low (exceptions surface during parallel testing)||High|
|Accuracy||To predetermine test cases, each methodology can’t be implemented with the same approach to ensure consistency.||Since the test strategies are often modified based on earlier findings, there is little chance of repetition.|
Regression testing is more involved than retesting, and the benefits of proceeding with this type of testing are considerable. However, there’s no denying that a coalition of retesting and regression testing is helpful in the long run because the thoroughness of the process considerably extends.