Modeling and Testing Hierarchical GUIs

This paper presents a new approach to model and test hierarchical Graphical User Interfaces (GUIs). We exploit the structure of Hierarchical Finite State Machines (HFSMs) to reduce the number of states in the ”flat” Finite State Machine (FSM) resulting from the exploration of the model. Firstly, independent dialogs are identified and highlighted in a HFSM built from the FSM. Then, the portion of the FSM that describes each dialog is reduced. To illustrate the approach, we construct a model of the Notepad application, which is part of Microsoft Windows. The model is written in Spec♯ and is converted automatically to a FSM using the Spec Explorer tool developed at Microsoft Research. The HFSM is then defined and the total number of states of the FSM is reduced. Spec Explorer generates test cases from the FSM, and also tests the conformity between the specification and the implementation.