Detecting Real Faults in the Gson Library Through Search-Based Unit Test Generation

An important benchmark for test generation tools is their ability to detect real faults. We have identified 16 real faults in Gson—a Java library for manipulating JSON data—and added them to the Defects4J fault database. Tests generated using the EvoSuite framework are able to detect seven faults. Analysis of the remaining faults offers lessons in how to improve generation. We offer these faults to the community to assist future research.