A Fault Based Approach to Test Case Prioritization

Regression testing is performed to ensure that the no new faults have been introduced in the software after modification and the software continues to work correctly. Regression testing is an expensive process because the test suite might be too large to execute in full. Thus to reduce the cost of such testing, regression testing techniques are used. One such technique is test case prioritization. Software testers assign priority to each test case to make sure that the test cases with higher priorities are executed first, in case of not having enough resources to execute the whole test suite. Test case prioritization is mainly used to increase fault detection rate of test suite which is the measure of how early faults are detected. In this paper, we propose an approach which exploits mutation testing in order to assign priorities to test cases. Using mutation testing, we introduce different faults in original program thus creating a number of mutated copies of the program and test case that exposes maximum number of these faults is given the highest priority. We report the outcomes of our experiments in which we applied our technique to test suites and calculated the fault detection rates produced by the prioritized test suites, comparing those rates of fault detection to the rates achieved by existing prioritization technique. The resulting data shows that prioritization technique proposed improved the fault detection rate of test suites.