It is common for the companies to introduce minor changes from time to time in their products. However, introducing these changes affect the application in numerous ways such as its functionality, performance, bugs, etc.
Therefore, it is important to keep the testing process on whether the software is present in the market or a small change has been introduced. Conducting this type of testing is known as regression testing.
Regression testing is a technique that is carried out by implementing units of code repeatedly so as to ensure that the constant code modifications are not impacting the system’s functionality.
These modifications can be done in numerous forms such as bug fixes, functionality, integrations, patches, etc.
While, there are many software developers who strongly believe that there is no need to retest a product unless there are some complications arising in its functionality, but that does not hold true in all cases.
Conducting regression testing can act as a real blessing as there are no chances of facing unexpected surprises.
Benefits of regression testing
While the basic aim behind conducting regression testing is to identify bugs that might have got developed due to the changes introduced, conducting this test benefits in a number of ways such as:
Types of regression testing
There are a number of ways in which regression testing can be done. However, this depends on factors such as the type of changes introduced, bugs fixed, etc. Some of the common types of regression testing include:
1) Corrective regression testing:
This type of regression testing is used when there are no changes introduced in the product’s specification. Moreover, the already existing test cases can be easily reused to conduct the desired test.
2) Retest-all regression testing:
This type of testing is very tedious and tends to waste a lot of time. The strategy involves the testing of all aspects of a particular product as well as reusing all test cases even where the changes/modifications have not been made. This type of regression testing is not at all advisable when there is a small change, that has been introduced in the existing product.
3) Selective regression testing:
It is done to analyze the impact of new code added to the already existing code of the software. When this type of regression testing is conducted, a subset from the existing test cases is used,to reduce the effort required for retesting and the cost involved. For example, a test unit is re-run in case there is some change incorporated in the program entities such as functions and variables.
4)Progressive regression testing:
This type of regression testing works effectively when there are certain changes done in the program specifications as well as new test cases are designed. Conducting this testing helps in ensuring that, there are no features that exist in the previous version that has been compromised in the new and updated version.
5) Complete regression testing:
Complete regression testing is the best to be used in case there are multiple changes that have been done to the already existing code. Moreover, this type of testing is specifically used when the new change has certain impact on the root code of the software. Conducting this type of testing is highly beneficial to identify unexpected issues. Once this testing is completed, the final system can be made available to the user.
It is important to make sure that the type of regression testing that needs to be conducted is selected appropriately.
This depends on various factors such as areas of recurrent defects, criticality of the features, etc. But, what remains on the priority is ensuring that the software delivers the best functionality and proves to be a beneficial addition to the industry.