Circumventing refactoring masking using fine-grained change recording

Today, refactoring reconstruction techniques are snapshot-based: they compare two revisions from a source code man-agement system and calculate the shortest path of edit op-erations to go from the one to the other. An inherent risk with snapshot-based approaches is that a refactoring may be concealed by later edit operations acting on the same source code entity, a phenomenon we call refactoring mask-ing. In this paper, we performed an experiment to find out at which point refactoring masking occurs and confirmed that a snapshot-based technique misses refactorings when several edit operations are performed on the same source code entity. We present a way of reconstructing refactorings using fine grained changes that are recorded live from an integrated development environment and demonstrate on two cases |PMD and Cruisecontrol| that our approach is more accurate in a significant number of situations than the state-of-the-art snapshot-based technique RefFinder.