Formalizing the ISO/IEC/IEEE 29119 Software Testing Standard

Model-based testing (MBT) provides a systematic and automated way to facilitate rigorous testing of software systems. MBT has been an intense area of research and a large number of MBT techniques have been developed in the literature and in the practice. However, all of the techniques have been developed using their own concepts and terminology of MBT, which are very often different than other techniques and at times have conflicting semantics. Moreover, while working on MBT projects with our industrial partners in the last several years, we were unable to find a unified way of defining MBT techniques based on standard terminology. To precisely define MBT concepts with the aim of providing common understanding of MBT terminology across techniques, we formalize a small subset of the recently released ISO/IEC/IEEE 29119 Software Testing Standard as a conceptual model (UML class diagrams) together with OCL constraints. The conceptual model captures all the necessary concepts based on the standard terminology that are mandatory or optional in the context of MBT techniques and can be used to define new MBT tools and techniques. To validate the conceptual model, we instantiated its concepts for various MBT techniques previously developed in the context of our industrial partners. Such instantiation automatically enforces the specified OCL constraints. This type of validation provided us feedback to further refine the conceptual model. Finally, we also provide our experiences and lessons learnt for such formalization and validation.