Fault localization techniques reduce the effort required when debugging software, as revealed by previous test cases. However, many test cases are required to reduce the number of candidate fault locations. To overcome this disadvantage, various methods were proposed to reduce fault-localization costs by prioritizing test cases. However, because a sufficient number of test cases is required for prioritization, the test-case generation cost remains high. This paper proposes a test-case generation method using a state chart to reduce the number of test suites required for fault localization, minimizing the test-case generation and execution times. The test-suite generation process features two phases: fault-detection test-case generation and fault localization in the test cases. Each phase uses mutation analysis to evaluate test cases; the results are employed to improve the test cases according to the objectives of each phase, using genetic algorithms. We provide useful guidelines for application of a search-based mutational method to a state chart; we show that the proposed method improves fault-localization performance in the test-suite generation phase.
Coverage criteria for test case generation using UML state chart diagram