基于EFSM模型的铁路信号安全软件单元测试技术研究

Unit testing technology for railway signal safety software based on EFSM model

铁路信号安全软件内部逻辑复杂,通过充分的单元测试能够更好地发现和排除软件内部的缺陷。文章分析单元测试常用方法,并结合铁路信号安全软件单元测试技术要求,提出一种基于扩展有限状态机(EFSM,Enhanced Finite State Machine)模型的黑白盒融合单元测试方法。使用自动化测试工具Cantata,以无线超时降级场景为实例,验证该方法是否可以满足测试场景的完备性,并且关注软件结构是否被完全覆盖。根据覆盖结果,对未覆盖原因进行分析,判断是否存在异常场景,并针对未覆盖分支补充测试场景,丰富了测试案例,从而保障了铁路信号系统的可靠性。

The internal logic of railway signal safety software is complex,and through sufficient unit testing,defects within the software can be better discovered and eliminated.This paper analyzed common methods of unit testing and proposed a black and white box fusion unit testing method based on the Extended Finite State Machine(EFSM) model,combined with the technical requirements of railway signal safety software unit testing.The paper used the automated testing tool Cantata as an example to verify whether the method can meet the completeness of the testing scenario and paied attention to whether the software structure was fully covered,analyzed the reasons for the lack of coverage based on the coverage results to determine whether there were abnormal scenarios,provided supplementary testing scenarios for the uncovered branches,which enriched the testing cases and ensured the reliability of the railway signal system.