Table of Contents
International Scholarly Research Notices
Volume 2014 (2014), Article ID 701357, 13 pages
Research Article

Bflinks: Reliable Bugfix Links via Bidirectional References and Tuned Heuristics

1Institut für Informatik, Freie Universität Berlin, 14195 Berlin, Germany
2Infopark AG, Kitzingstraße 15, 12277 Berlin, Germany

Received 25 March 2014; Accepted 16 September 2014; Published 29 October 2014

Academic Editor: Francesco Camastra

Copyright © 2014 Lutz Prechelt and Alexander Pepper. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Background. Data from software version archives and defect databases can be used for defect insertion circumstance analysis and defect prediction. The first step in such analyses is identifying defect-correcting changes in the version archive (bugfix commits) and enriching them with additional metadata by establishing bugfix links to corresponding entries in the defect database. Candidate bugfix commits are typically identified via heuristic string matching on the commit message. Research Questions. Which filters could be used to obtain a set of bugfix links? How to tune their parameters? What accuracy is achieved? Method. We analyze a modular set of seven independent filters, including new ones that make use of reverse links, and evaluate visual heuristics for setting cutoff parameters. For a commercial repository, a product expert manually verifies over 2500 links to validate the results with unprecedented accuracy. Results. The heuristics pick a very good parameter value for five filters and a reasonably good one for the sixth. The combined filtering, called bflinks, provides 93% precision and only 7% results loss. Conclusion. Bflinks can provide high-quality results and adapts to repositories with different properties.