A Test Path Generation Method Based on SSM Models

The traditional finite state machine (FSM) cannot express complicated systems due to its flattened sequential features. A safe state machine (SSM) is an extension of FSMs with capability of expressing hierarchical structure, parallel structure and historical mechanism. Therefore, it can accurately express complicated functions of a system, and SSMs have strict formal semantics. This paper provides a method for generating test paths based on SSMs. A method of creating the reachability graph (RG) of an SSM is presented, which can eliminate the hierarchical and parallel structure, and mark the history states. Finally, test paths are generated based on certain test coverage criteria of the RG mode.