An Experimental Determination of Su cient Mutation Operators

Mutation testing is a technique for unit testing software that, although powerful, is computationally expensive. The principal expense of mutation is that many variants of the test program, called mutants, must be repeatedly executed. Selective mutation is a way to reduce the cost of mutation testing by reducing the number of mutants that must be executed. This paper reports experimental results that compare selective mutation testing to standard, or non-selective, mutation testing. The results support the hypothesis that selective mutation is almost as strong as non-selective mutation; in experimental trials selective mutation provides almost the same coverage as non-selective mutation, with a four-fold or more reduction in cost.