On The Effect Of Code Review On Code Smells
This addresses code quality improvement for software developers, but the findings are incremental as they confirm existing expectations with nuanced details.
The study investigated whether code review influences the severity of code smells, analyzing over 21,000 code reviews from seven Java open-source projects and finding that active reviews significantly reduce smell severity, but manual analysis of 365 cases showed 95% of reductions were side effects of unrelated changes.
Code smells are symptoms of poor design quality. Since code review is a process that also aims at improving code quality, we investigate whether and how code review influences the severity of code smells. In this study, we analyze more than 21,000 code reviews belonging to seven Java open-source projects; we find that active and participated code reviews have a significant influence on the likelihood of reducing the severity of code smells. This result seems to confirm the expectations around code review's influence on code quality. However, by manually investigating 365 cases in which the severity of a code smell in a file was reduced with a review, we found that-in 95% of the cases-the reduction was a side effect of changes that reviewers requested on matters unrelated to code smells. Data and materials [https://doi.org/10.5281/zenodo.3588501].