A systematic literature review of clone evolution

Abstract

Code clones are identical or nearly similar code fragments often introduced into software systems by programmers with software modification and maintenance. During the evolution of the software system, code clones may experience multiple changes, such as the increase in number, disappearance, location change, etc. These changes increase the difficulty of clone management and possibly introduce bugs into the software, leading to the high price of clone management and maintenance. Therefore, it is necessary to study the clone evolution. In this paper, we summarize the research works in code clone evolution in recent decades. Based on the previous review and survey, we found a total of 47 relevant papers and divided them into five categories with the help of the LDA model. We present our analysis of the current research and discussion about the possible future progress in this paper. The final result of the debate is that we believe the future work will divide into two aspects. On the one hand, developing clone management tools based on the current results become a possible direction; on the other hand, development and improvement may appear in existing tools with more theoretical support due to more knowledge of the evolutionary characteristics of clones.