Mutant Minimization for Model-Checker Based Test-Case Generation

Mutation of model-checker specifications is used to generate test-cases automatically. In general, model-checker based techniques are efficient when using small, abstract models, but are limited in their applicability by the performance of the model-checker. Issues that contribute to potentially bad performance are equivalent mutants which result in no test-cases, and the fact that many different mutants lead to identical or subsumed test-cases. Another drawback of such approaches is that the size of resulting test-suites can be rather large, which might require test-suite reduction as an additional post-processing step. In this paper, we describe how the number of mutants can be minimized with special properties, which help to detect equivalent mutants more quickly and to avoid the creation of redundant test-cases. Consequently, the size of created test-suites is reduced.