Automated Bug Finding in Video Games: A Case Study for Runtime Monitoring

Runtime verification is the process of observing a sequence of events generated by a running system and comparing it to some formal specification for potential violations. We show how the use of a runtime monitor can greatly speed up the testing phase of a video game under development, by automating the detection of bugs when the game is being played. We take advantage of the fact that a video game, contrarily to generic software, follows a special structure that contains a "game loop", this game loop can be used to centralize the instrumentation and generate events based on the game's internal state. We report on experiments made on a sample of five real-world video games of various genres and sizes, by successfully incrementing and efficiently monitoring various temporal properties over their execution-including actual bugs reported in the games' bug tracking database in the course of their development.