Understanding JavaScript Event-Based Interactions with Clematis
Saba Alimadadi, Sheldon Sequeira, Ali Mesbah, Karthik Pattabiraman · ACM Transactions on Software Engineering and Methodology · 2016
Web applications have become one of the fastest-growing types of software systems today. Despite their popularity, understanding the behavior of modern web applications is still a challenging endeavor for developers during development and maintenance tasks. The challenges mainly stem from the dynamic, event-driven, and asynchronous nature of the JavaScript language. We propose a generic technique for capturing low-level event-based interactions in a web application and mapping those to a higher-level behavioral model. This model is then transformed into an interactive visualization, representing episodes of triggered causal and temporal events, related JavaScript code executions, and their impact on the dynamic DOM state. Our approach, implemented in a tool called C lematis , allows developers to easily understand the complex dynamic behavior of their application at three different semantic levels of granularity. Furthermore, C lematis helps developers bridge the gap between test cases and program code by localizing the fault related to a test assertion. The results of our industrial controlled experiment show that C lematis is capable of improving the comprehension task accuracy by 157% while reducing the task completion time by 47%. A follow-up experiment reveals that C lematis improves the fault localization accuracy of developers by a factor of two.