Projected state machine coverage for software testing

Our research deals with test generation for software based on finite state machine (FSM) models of the program specification. We describe a set of coverage criteria and testing constraints for use in the automatic generation of test suites. We also describe the algorithms used to generate test suites based on these coverage criteria, and the implementation of these algorithms as an extension of the Murφ model checker. The coverage criteria are simple but powerful in that they generate test suites of high quality and moderate volume, without requiting the user to have a sophisticated grasp of the test generation technology. The testing constraints are used to combat the endemic problem of state explosion, typically encountered in FSM techniques. We illustrate our techniques on several well-known problems from the literature and describe two industrial trials, to demonstrate the validity of our claims.