Using Version Control History to Follow the Changes of Source Code Elements

Version control systems store the whole history of the source code. Since the source code of a system is organized into files and folders, the history tells us the concerned files and their changed lines only but software engineers are also interested in which source code elements (e.g. classes or methods) are affected by a change. Unfortunately, in most programming languages source code elements do not follow the file system hierarchy, which means that a file can contain more classes and methods and a class can be stored in more files, which makes it difficult to determine the changes of classes by using the changes of files. To solve this problem we developed an algorithm, which is able to follow the changes of the source code elements by using the changes of files and we successfully applied it on the Web Kit open source system.