Differencing Graphical User Interfaces

Graphical User Interface (GUI)-based APplications (GAPs) are ubiquitous and provide a wealth of sophisticated services. Nontrivial GAPs evolve through many versions, and understanding how GUIs of different versions of GAPs differ is crucial for various software quality tasks such as testing, cross-platform UI comparison and project effort estimation. Yet despite the criticality of automating GUI differencing, it is a manual, tedious, and laborious task. We offer a novel approach for differencing GUIs that combines tree edit distance measure algorithms with accessibility technologies for obtaining GUI models in a non-intrusive, platform and language-independent way, and it does not require the source code of GAPs. We developed a tool called GUI DifferEntiator (GUIDE) that allows users to difference GUIs of running GAPs. To evaluate GUIDE, we created an experimental platform that generates random GUIs with controlled differentials among them that serve as oracles. GUIDE enables researchers to plug-and-play various GUI differencing algorithms and to automatically run experiments. We evaluated GUIDE on 5,000 pairs of generated complex GUIs and three open-source GAPs and the results of our evaluation suggest that GUIDE can find differences between GUIs with a high degree of automation and precision.