Metamorphic Testing in Fault Localization of Model Transformations

Model transformations are cornerstone elements of Model Driven Engineering (MDE), and their quality directly affects the successful application of MDE in practice. However, due to the characteristics of model transformation programs, the debugging of model transformations faces the oracle problem. In this paper, we propose an approach of debugging model transformations by using the technique of metamorphic testing (MT). Our approach leverages MT to alleviate the oracle problem, and integrates MT with spectrum-based fault localization technique to locating faulty rules of model transformations. We conduct experiments to evaluate our approach by using open-source model transformation programs, and compare the effectiveness of our approach with that of a fault localization technique using constraint-based oracles. Both of the experimental analysis and the comparison study show that our approach is of promising effectiveness, suggesting that MT can be a good support for debugging model transformations.