Towards a prioritization of code debt: A code smell Intensity Index

Code smells can be used to capture symptoms of code decay and potential maintenance problems that can be avoided by applying the right refactoring. They can be seen as a source of technical debt. However, tools for code smell detection often provide far too many and different results, and identify many false positive code smell instances. In fact, these tools are rooted on initial and rather informal code smell definitions. This represents a challenge to interpret their results in different ways. In this paper, we provide an Intensity Index, to be used as an estimator to determine the most critical instances, prioritizing the examination of smells and, potentially, their removal. We apply Intensity on the detection of six well known and common smells and we report their Intensity distribution from an analysis performed on 74 systems of the Qualitas Corpus, showing how Intensity could be used to prioritize code smells inspection.