Using Dynamic Symbolic Execution to Generate Inputs in Search-Based GUI Testing

Search-based testing has been successfully applied to generate complex sequences of events for graphical user interfaces (GUIs), but typically relies on simple heuristics or random values for data widgets like text boxes. This may greatly reduce the effectiveness of test generation for applications which expect specific input values to be entered in their GUI by users. Generating such specific input values is one of the virtues of dynamic symbolic execution (DSE), but DSE is less suitable to generate sequences of events. Therefore, this paper describes a hybrid approach that uses search-based testing to generate sequences of events, and DSE to build input data for text boxes. This is achieved by replacing standard widgets in a system under test with symbolic ones, allowing us to execute GUIs symbolically. In this paper, we demonstrate an extension of the search-based GUI testing tool EXSYST, which uses DSE to successfully increase the obtained code coverage on two case study applications.