Generating test case from symbolic transition systems based on constrained unfolding
Résumé
Symbolic transition systems (STS) are an adequate formalism for the finite specification of infinite state models. We propose to generate test cases to check whether a system behaves correctly or not according to its specification given in terms of an STS. Success or failure verdicts are emitted with respect to an adequate conformance relation. However, these verdicts may become ambiguous in presence of non observable state variables or non-determinism. We present an algorithm which computes test cases according to a test purpose denoting selected behaviours of the specification. This algorithm uses an on-the-fly execution of the test cases and the unfolding of the specification by means of its symbolic execution. The first execution data allow to constrain the specification unfolding in order to guide the selection of the next data to be selected in the test case scenario. We demonstrate our approach on a simple example.