SIG-Droid: Automated System Input Generation for Android Applications

Pervasiveness of smartphones and the vast number of corresponding apps have underlined the need for applicable automated software testing techniques. A wealth of research has been focused on either unit or GUI testing of smartphone apps, but little on automated support for end-to-end system testing. This paper presents SIG-Droid, a framework for system testing of Android apps, backed with automated program analysis to extract app models and symbolic execution of source code guided by such models for obtaining test inputs that ensure covering each reachable branch in the program. SIG-Droid leverages two automatically extracted models: Interface Model and Behavior Model. The Interface Model is used to find values that an app can receive through its interfaces. Those values are then exchanged with symbolic values to deal with constraints with the help of a symbolic execution engine. The Behavior Model is used to drive the apps for symbolic execution and generate sequences of events. We provide an efficient implementation of SIG-Droid based in part on Symbolic PathFinder, extended in this work to support automatic testing of Android apps. Our experiments show SIG-Droid is able to achieve significantly higher code coverage than existing automated testing tools targeted for Android.