With the continuous development of the railway transportation system, train operation control is becoming more and more significant as the core to guarantee the operational safety and efficiency. Train control based on Global Navigation Satellite System (GNSS) is an important way to improve on-board sub-system autonomy and reduce the dependence on trackside facilities. However, the vulnerability of GNSS makes GNSS-based train positioning susceptible to the spoofing attack, which affects its ability to be used for novel train control systems. For this reason, it is of great significance to conduct specific test and evaluation for train positioning research, development, and applications. In this study, we construct an overall framework of spoofing injection test for GNSS-based positioning in train control, and analyze the detailed contents of test and evaluation, including spoofing attack configuration, test scenario design and generation, test dataset establishment and analysis, and typical evaluation metrics. In order to fully demonstrate the effectiveness of the proposed framework, a complete spoofing injection test environment is established. Through case studies concerning two typical spoofing modes, we successfully illustrate the effectiveness of the proposed scheme in testing and evaluating the spoofing tolerant capability and performance features of GNSS receivers dedicated to train positioning. Finally, we discuss the direction of subsequent trusted applications of GNSS in train control systems using the presented solution and platform. The results provide relevant ideas for the research of novel GNSS spoofing protection techniques for future intelligent railway systems.