Understanding feature evolution in a family of product variants

Existing software product variants, developed by ad hoc reuse such as copy-paste-modify, are often a starting point for building Software Product Line (SPL). Understanding of how features evolved in product variants is a prerequisite to transition from ad hoc to systematic SPL reuse. We propose a method that assists analysts in detecting changes to product features during evolution. We first entail that features and their inter-dependencies for each product variant are documented as product feature model. We then apply model differencing algorithm to identify evolutionary changes that occurred to features of different product variants. We evaluate the effectiveness of our approach on a family of medium-size financial systems. We also investigate the scalability of our approach with synthetic data. The evaluation demonstrates that our approach yields good results and scales to large systems. Our approach enables the subsequent variability analysis and consolidation of product variants in the task of reengineering product variants into SPL.