Regression Testing with Regression Testing Tools and methods

What is Regression Software Testing?
Regression means retesting the unchanged parts of the application. Test cases are re-executed in order to check whether previous functionality of application is working fine and new changes have not introduced any new bugs.

This is the method of verification. Verifying that the bugs are fixed and the newly added feature have not created in problem in previous working version of software.

Why regression Testing?
Regression testing is initiated when programmer fix any bug or add new code for new functionality to the system. It is a quality measure to check that new code complies with old code and unmodified code is not getting affected.
Most of the time testing team has task to check the last minute changes in the system. In such situation testing only affected application area in necessary to complete the testing process in time with covering all major system aspects.

How much regression testing?
This depends on the scope of new added feature. If the scope of the fix or feature is large then the application area getting affected is quite large and testing should be thoroughly including all the application test cases. But this can be effectively decided when tester gets input from developer about the scope, nature and amount of change.

What we do in regression testing?

• Rerunning the previously conducted tests
• Comparing current results with previously executed test results.

Regression Testing Tools:
Automated Regression testing is the testing area where we can automate most of the testing efforts. We run all the previously executed test cases this means we have test case set available and running these test cases manually is time consuming. We know the expected results so automating these test cases is time saving and efficient regression testing method. Extent of automation depends on the number of test cases that are going to remain applicable over the time. If test cases are varying time to time as application scope goes on increasing then automation of regression procedure will be the waste of time.

Most of the regression testing tools are record and playback type. Means you will record the test cases by navigating through the AUT and verify whether expected results are coming or not.
Example regression testing tools are:

* Win runner
* QTP
* AdventNet QEngine
* Regression Tester
* vTest
* Watir
* Selenium
* actiWate
* Rational Functional Tester
* SilkTest

Most of the tools are both Functional as well as regression testing tools.

Regression Testing Of GUI application:
It is difficult to perform GUI(Graphical User Interface) regression testing when GUI structure is modified. The test cases written on old GUI either becomes obsolete or need to reuse. Reusing the regression testing test cases means GUI test cases are modified according to new GUI. But this task becomes cumbersome if you have large set of GUI test cases.