Mutation Testing for Evaluating the Completeness of Test Cases in High-Speed Train Control System

As the high-speed train control system is a typical safety-critical system, it is vitally important to guarantee its correctness. Testing is a significant technical method to ensure the safety and reliability of high-speed train control system. For a long time, how to generate test cases and how to ensure their completeness are the key issues in the testing of train control system, which have a direct bearing on the efficiency and quality of the testing. Mutation testing, which can simulate most kinds of fault models of the system, provides an alternative or complementary method to measure test sufficiency. At the same time, new test cases can be generated by mutation analysis if the completeness of the test cases is not enough, which are added in the test case set to improve its completeness. In this paper, we introduce the mutation testing based on Timed Automata (TA), which is suitable for analyzing the high-speed train control system and evaluating the completeness of the test cases. Firstly, we analyze the main functions of the typical scenario of RBC handover process and use TA theory to model it. Secondly, test cases of the scenario are evaluated and we get the index to donate the completeness of them. Finally, we generate more sufficient test cases by constantly looking for test cases that have stronger fault detection ability.