Regression testing makes sure that newly added features or updates to software don't break any existing functionality and function as intended following a change. Regression testing requires a significant amount of time and effort, which is often underestimated by development and testing teams. This results in releases with many bugs, poor user experiences, and unhappy customers. In this post, let's discuss different types of regression testing and the ideal scenarios to use them.

When should you perform regression testing?
Companies must ideally perform regression testing on a regular basis: on-demand or on a schedule.
When there is the addition of a new feature: When new functionality is implemented, regression testing is typically performed by developers/testers. It helps the development team save a ton of time by quickly identifying flaws at the development stage that, if discovered later, would have severely damaged the software.
When the current strategy is updated: Sometimes, unexpected changes in the existing business strategy can result in a complete modification of the current functionality. Regression testing is absolutely necessary for these situations since the substantial change in the source code can seriously damage other functionalities.
After the bugs are fixed: Sometimes when developers attempt to fix one issue, it results in additional errors. Performing debugging with regression testing ensures no new bugs were found after debugging and that everything functioned as intended.
Types of regression testing
Here are the seven types of regression testing:

1. Corrective regression testing
   ‍This form of regression testing is utilized when the product's specifications remain unchanged. Moreover, the current test cases can be reused to perform the expected test.

2. Retest-all regression testing
   Retest-all regression testing is a challenging testing method. It examines each very tiny modification made to the software since it was created. The most typical case for retesting occurs when other regression tests have failed to identify the issue and development teams assume the issue was caused by recent code modifications.

You can read more about this in our blog post: The difference between retesting and regression testing

1. Selected regression testing
   It is performed to determine how the code behaves when new code is added to the existing code. To reduce the time and expense required for retesting, this type of regression testing uses a subset of the current test cases.

2. Progressive regression Testing
   This kind of regression testing yields more informative findings when new test cases are created for specific program modifications. By conducting this testing, you can make sure that the most recent and revised version doesn't contain any elements from the older version that could be vulnerable.

3. Complete regression Testing
   Regression testing is best applied when the existing code has undergone many updates. This kind of testing is helpful in finding bugs that frequently go undetected. The final software version can be made accessible to users once all regression testing is finished.

4. Partial Regression Testing
   This type of software regression testing is carried out to confirm the problems that arise when new code is deployed to existing code. Assuring that a system works as intended once the new code is added is done through partial regression testing.

5. Unit Regression Testing
   It is a critical kind of regression testing that is generally done alone and is concentrated on code units. Unit regression testing forbids all dependencies and interactions and is performed independently.

Regression testing is one of the most tedious and time-consuming tasks in the software development and testing process. Therefore, automating your regression process offers a higher-quality product at a cheaper cost and faster release.‍

Regression testing can be done manually, however, when software systems develop or change, the number of test cases and the regression suite will also increase. It’ll reach a point where it’s no longer feasible to manage the regression test suites manually. Due to its repeated and predictable nature, you need to opt for an automated regression testing tool. That will enable you to easily maintain your regression suites and allow you to make modifications and updates without having to write new code. No-code automation tools for regression testing offer a higher-quality product at a cheaper cost and faster release.

Read more about how no-code automation can help customers reduce the costs, effort, and timeliness of their regression testing.