It is very common for companies to make minor changes in applications or software from time to time. However, making these changes also affect the functionality and performance of the software. The software may also become buggy. So, it is imperative to test the functionality of the software after making changes.
The types of testing used in these kinds of cases are known as “Regression Testing.” Regression testing is a process that’s carried out by the execution of code repeatedly to ensure that the code is working fine after making changes. The changes or modifications can be of multiple like fixing bugs, patches, functionality, integration, etc.
The types of regression testing are different, which are based on the code and condition of the test cases. There are so many phases of regression due to this; regression has various types. Few of them have been mentioned below.
1 Progressive regression testing
This type of regression testing is helpful when the changes are made in the specification of the program. In this case, instead of using the previous test case, developers have to create a new test case. By using this method of regression testing ensures that there is no earlier version of the application or software is in use while the testing process. The testing process is based on the parent-child hierarchy of the application. This testing approach has further three different ways of testing which are as follows:-
- Top-down testing method
- Bottom-up testing method
- Hybrid testing method
All the above-motioned methods of regression testing are used based on the requirement of testing.
2 Selective regression testing
This kind of testing is used to figure out the impact of newly added code to the previously existing code of the application or software. In selective regression testing, a subset of the already existing code is being used as the test case. This selection process helps to reduce the cost and efforts needed for testing processes. The selection of the existed code dependent upon the section where changes are made. According to experts, with the addition of new code, only the module where it is added got affected. This method of regression testing is considered as the most complex. The reason behind this is that if you select the wrong code as a test case, then you will never figure out the actual impact of newly added code. Due to this, some bugs will remain inside your application.
3 Reset all regression testing
This is a very time consuming and tedious method of regression testing. As the name describes itself, in this type of testing, all the aspects of a product or software or application are tested from the start. It doesn’t care about changes or modifications. According to this method, the application has to test from the starting line to check the effect of modification on the whole product instead of a specific module. If you have made small changes in your application, then we would not recommend you to do this type of testing in your application. But yes, in case of significant changes, you should run this testing.
Also, if your application or software is small, then don’t waste your time in performing this testing. Usually, tester runs away from resetting all testing. The primary reason behind this is that the reset all testing needs all fresh and new test cases. You cannot implement previous test cases. This process needs so much time and also concentration to get something new so that it can become presentable as a test case. Be careful while choosing this testing method to test your software or application.
4 Complete regression testing
Complete regression testing considered as the best method in regression testing. The testing method is best to use when you have done multiple changes to the already available code. This testing is helpful, especially for those cases, when the changes are done on the root code of the application or software. With the help of complete regression testing, you will be able to find some unexpected issues in the application. Most of the times, the testing is done on the final products before making it available to the users.
It is advisable that don’t use regression testing all the times. The testing is suitable for some special occasions like at the completion of the product. The most common reason for using this testing method is that the code produces after testing will be bug-free and more efficient than the old code.
5 Unit regression testing
Unit testing is an essential form of regression testing. The method is mostly implemented on the specific or one module of the application at one time. In this process, all the interactions and dependencies of the module with the rest of the application will be blocked for some time, or we can say at the time of testing. Before performing all other methods of testing, you have to perform unit testing. Because by this you will get ensured that each module is working fine without dependencies. And also if you find bugs, then it is easy to remove because you are working with one module at one time.
The unit regression testing helps to check out various factors of the module like its defects, functionality, robustness, efficiency, reliability, etc. So, don’t forget unit regression testing for the best functional software or application.
In the field of dynamic software, there are so many different methods available to test the application. But it is the choice of the developer and tester to choose one for the application. According to time and demands of the users, they have to make so many changes in the application. To make sure that due to changes, the functionality of the application is not affecting regression testing is very important.
To perform regression testing techniques, you have to keep in mind that testers give importance to regression testing automated tools to decrease the efforts and time.