Code Complexity and Version History for Enhancing Hybrid Bug Localization

Software projects are not void from bugs when they are released, so the developers keep receiving bug reports that describe technical issues. The process of identifying the buggy code files that correspond to the submitted bug reports is called bug localization. Automating the bug localization process can speed up bug fixing and improve the productivity of the developers, especially with a large number of submitted bug reports. Several automatic bug localization approaches were proposed in the literature reviews which are based on the textual and /or semantic similarity among the bug reports and the source code files. Nevertheless, none of the previous approaches made use of the source code complexity despite its importance; as high complexity source code files have higher probabilities to be modified than the low complexity files and are prone to bug occurrences. To improve the accuracy of the automatic bug localization task, this paper proposes a Hybrid Bug Localization approach (HBL) that makes full use of textual and semantic features of source code files, previously fixed bug reports, in addition to the source code complexity and version history properties. The effectiveness of the proposed approach was assessed using three open-source Java projects, ZXing, SWT, and AspectJ, of different sizes. Experimental results showed that the proposed approach outperforms several state-of-the-art approaches in terms of the mean average precision (MAP) and the mean reciprocal rank (MRR) metrics.