Software

An Empirical Study of Long-Lived Code Clones

Date Added: Dec 2010
Format: PDF

Previous research has shown that refactoring code clones as soon as they are formed or discovered is not always feasible or worthwhile to perform, since some clones never change during evolution and some disappear in a short amount of time, while some undergo repetitive similar edits over their long lifetime. Toward a long-term goal of developing a recommendation system that selectively identifies clones to refactor, as a first step, the authors conducted an empirical investigation into the characteristics of long-lived clones. Their study of 13558 clone genealogies from 7 large open source projects, over the history of 33.25 years in total, found surprising results.