Normalizing source code vocabulary to support program comprehension and software quality

摘要

The literature reports that source code lexicon plays a paramount role in program comprehension, especially when software documentation is scarce, outdated or simply not available. In source code, a significant proportion of vocabulary can be either acronyms and-or abbreviations or concatenation of terms that can not be identified using consistent mechanisms such as naming conventions. It is, therefore, essential to disambiguate concepts conveyed by identifiers to support program comprehension and reap the full benefit of Information Retrieval-based techniques (e.g., feature location and traceability) whose linguistic information (i.e., source code identifiers and comments) used across all software artifacts (e.g., requirements, design, change requests, tests, and source code) must be consistent. To this aim, we propose source code vocabulary normalization approaches that exploit contextual information to align the vocabulary found in the source code with that found in other software artifacts. We were inspired in the choice of context levels by prior works and by our findings. Normalization consists of two tasks: splitting and expansion of source code identifiers. We also investigate the effect of source code vocabulary normalization approaches on software maintenance tasks. Results of our evaluation show that our contextual-aware techniques are accurate and efficient in terms of computation time than state of the art alternatives. In addition, our findings reveal that feature location techniques can benefit from vocabulary normalization when no dynamic information is available.