Examining the Co-Evolution Relationship Between Simulink Models and their Test Cases

This paper presents an industrial case study that explores the co-evolution relationship between Matlab Simulink Models and their associated test suites. Through an analysis of differences between releases of both the models and their tests, we are able to determine what the relation between the model evolution and test evolution is, or if one exists at all. Using this comparison methodology, we present empirical results from a production system of 64 Matlab Simulink Models evolving over 9 releases. In our work we show that in this system there is a strong co-evolution relationship (a correlation value of r = 0.9, p <; 0.01) between the models and tests, and we examine the cases where the relationship does not exist. We also pose, and answer, three specific research questions about the practices of development and testing over time for the system under study.