Automated Measure of Structural Coverage for LUSTRE Programs: a Case Study

Lustre is a synchronous data-flow declarative language widely used for safety-critical applications (avionics, energy, transport). Scade is a commercial tool-suite based on this language. We have proposed recently test coverage criteria for Lustre/Scade programs. The coverage assessment is fully automated and has been integrated in a prototype tool, Lustructu. This tool analyzes Lustre programs and extracts the conditions that a test input sequence must verify in order to meet a criterion. The associated measures are fully automated and non-intrusive. In this paper we present a case study that applies the coverage criteria to an alarm management software specification developed in Scade. The case study is used to illustrate the defined criteria as well as to evaluate their applicability and usefulness.