A theoretical analysis on cloning the failed test cases to improve spectrum-based fault localization

In this paper, we report a comprehensive study to investigate the impact of cloning the failed test cases on the effectiveness of SBFL techniques. We include 33 popular such techniques, and examine the accuracy of their formulas on twelve benchmark programs, using four accuracy metrics and in three scenarios. The empirical results show that on 22, 21, and 23 of them the fault-localization accuracy can be significantly improved, when the failed test cases are cloned in the single-fault, double-fault, and triple-fault scenarios, respectively. We also analytically show that on 19 of them the improvements are provable for an arbitrary program and an arbitrary test suite, in the single-fault scenario; and moreover, for ten of the rest formulas, their accuracy are proved unaffected in all scenarios.