“Testing Can Be Formal Too”: 30 Years Later

This chapter relates a series of works that contributed to the recognition of the use of formal specifications when testing software. After presenting a first set of results on test methods based on algebraic data types, generalisations to other formal approaches are described. The outcome of several case studies is reported, and as conclusion, the place of formal testing within the software validation and verification activities is discussed. A concrete example is developed in appendix.