PrototypeFileRepo implements functionality of a ``prototype'' test data repository. (See section 3.3.1).
PrototypeFileRepo is a subclass of TempFileRepo. It creates temporary files by copying files from another repository, i.e., another Repo instance.
PrototypeFileRepo uses Composite design pattern. Class Repo is among the subclasses of PrototypeFileRepo and it is also a member of PrototypeFileRepo.