Inferring Types of References to GUI Objects in Test Scripts

Since manual black-box testing of GUI-based applications (GAPs) is tedious and laborious, test engineers create test scripts to automate the testing process. These test scripts interact with GAPs by performing actions on their GUI objects. Unlike conventional languages that require programmers to declare types of variables explicitly, test script statements reference GUI objects using their properties (e.g., location, color, size, etc). The absence of type information exacerbates the process of understanding test scripts, making maintenance and evolution of these scripts expensive and prohibitive, thus obliterating benefits of test automation. We offer a novel approach for type inference of GUI object references (TIGOR) in test scripts. TIGOR makes types of GUI objects explicit in the source code of scripts, enabling test engineers to reason more effectively about the interactions between operations in complex test scripts and GUI objects that these operations reference. We describe our implementation and give an algorithm for automatically inferring types of GUI objects. We built a tool and evaluated it on different GAPs. Our experience suggests that TIGOR is practical and efficient, and it yields appropriate types of GUI objects.