Debugging Process Algebra Specifications

International audienceDesigning and developing distributed and concurrent applications has always been a tedious and error-prone task. In this context, formal techniques and tools are of great help in order to specify such concurrent systems and detect bugs in the corresponding models. In this paper, we propose a new framework for debugging value-passing process algebra through coverage analysis. We illustrate our approach with LNT, which is a recent specification language designed for formally modelling concurrent systems. We define several coverage notions before showing how to instrument the specification without affecting original behaviors. Our approach helps one to improve the quality of a dataset of examples used for validation purposes, but also to find ill-formed decisions, dead code, and other errors in the specification. We have implemented a tool for automating our debugging approach, and applied it to several real-world case studies in different application areas

Test Generation Based on Abstraction and Test Purposes to Complement Structural Tests

International audienceThis paper presents a computer aided model-based test generation method. We propose this approach as a complement to the LTG (Leirios Test Generator) method, which extracts functional tests out of a formal behavioral model M by means of static (or structural) selection criteria. Our method computes additional tests by applying dynamic (or behavioral) selection criteria (test purposes called TP). Applying TP directly to M is usually not possible for industrial applications due to the huge (possibly infinite) size of their state space. We compute an abstraction A of M by predicate abstraction. We propose a method to define a set of abstraction predicates from information of TP. We generate symbolic tests from A by using TP as a dynamic selection criterion. Then we instantiate them on M, which allows us play the tests on the implementation the same way as we play the functional ones. Our experimental results show that our tests are complementary to the structural ones