Models for synchronous software testing

Because it is usually involved in critical application development, synchronous software requires thorough testing. During the last ten years, several testing techniques have been integrated in Lutess, a testing tool for Lustre-based applications. This paper presents the models on which these techniques are defined: functional models and structural models. The first class deals with behavioral aspects of synchronous software and it's built on input/output finite state machine specifications. The second deals with structural aspects of Lustre programs or specifications and is based on operator networks, usual representation of Lustre programs. For each class of models, we have defined adequacy criteria. They serve either to measure testing quality (coverage) or to assist in the test data generation. The latter may be performed randomly or guided.