Regression testing is an important step in software development that helps determine the functionality of an application after it has been altered or integrated with new software. These changes can be anything from patches (an update to a computer program) to software enhancements and configuration changes. The aim of regression testing is to uncover software bugs, also called regressions, that may alter the functioning of the original application.
Regression testing is essential to the development of a quality application that will run as intended. It also increases the stability and reliability of your software.
The regression testing services provide a rigorous and thorough analysis of your application software to ensure that no new bugs or performance issues are introduced at any stage of the development process.
The various regression testing techniques are as follows:
1. Execution of test cases:
Also known as the 'test all' technique, this involves testing all the test cases for a particular release. Although this is a time consuming and expensive process as all the test cases need to be re-executed, in the long run it is a very effective method of ensuring that there are no errors introduced due to code changes.
2. Regression test selection:
Unlike test all, only a part of the collection of test cases are re-executed. The test cases selected depend on the changes made to the application. In comparison to the test all method, test selection is more cost effective.
3. Prioritizing test cases:
Test cases are prioritized based on dependencies, business impact and criticality. This technique greatly reduces the number of test cases to be checked. Test cases with a higher priority will be re-executed first.
There are two main types of test prioritization:
i. General Specific
ii. Version Specific
In general prioritization, tests that will be beneficial in succeeding versions are checked first whereas in Version specific testing test cases with respect to a certain version are run first. uses a risk-based testing methodology for prioritizing test cases.
4. The need for regression testing:
Any change to the original application code brings with it the risk of generating defects. To maintain the integrity of the code, it is essential to perform testing every time a change is made. By conducting testing every time a change a made, it will be easier to detect and resolve bugs.
Regression testing not only improves the functionality of the program but also improves the quality of the output.
Time and money constraints are the biggest hindrance to regression testing. With successive test runs, the number of test cases keeps increasing and it becomes more difficult to test the entire application.
Despite the cost and time-consuming nature of regression testing, it is a crucial step in software development.
According to studies, regression testing saves up to 60% time in bug fixing and between 10-40% in money.
It helps in maintenance of the application, reduces bugs, and saves time and money.
7. Automated regression testing :
Automated regression testing which ensures that the detected errors are corrected with each new release and no new bugs are introduced in the process. Automated testing units can be built-in that run every time a change is made to the code. Automation reduces the amount of work by a significant margin as running regression tests manually is very labour-intensive.
Ensures an extensive testing process that will keep your application running smoothly and your projects on track.