Language-Based Testing for Knowledge Graphs

Knowledge graphs rely on a vast ecosystem of software tools, such as parsers, APIs and reasoners. Yet, tool developers have little support to ensure tool reliability. Here, we demonstrate how recent advantages in test case generation for highly structured and constrained inputs can support software developers in the semantic web field. We develop input generators for RDF Turtle and the OWL EL profile, and report on numerous bugs we found in parsers, reasoners and APIs of widely used tools and libraries, as well as imprecisions in standards and documentation. We provide actionable insights on using automated testing to increase the reliability of software tools for knowledge graphs.