Revisiting Program Suitability for Fault Localization with Large Dataset and Various Mutation Operators

Spectrum-Based Fault Localization (in short, SBFL) is one of the popular techniques to localize faulty statements of a given program. SBFL utilizes the information about which statements are executed in each of the successful or failed test cases. Even if multiple programs have the same functionality, the accuracy of SBFL can differ due to their structural variations. Thus, changing program structures to be suitable for SBFL may improve the accuracy of fault localization while maintaining functionality. In previous research by Sasaki et al, SBFL-Score was proposed to discover program structures suitable for SBFL. SBFL-Score is one of the metrics used to evaluate how well a program is suitable for SBFL. Furthermore, the previous research measured SBFL-Scores for pairs of programs with different structures but the same functionality, and obtained a program structure suitable for SBFL. However, a small number of programs and a small number of mutation operators used in the experiments were shortcomings. Thus, in this study, we conducted an experiment with approximately 36 times more programs and about 2.5 times more mutation operators than in the previous research. As a result of this experiment, we identified four new program structures suitable for SBFL.