Unit Testing in ASP Revisited: Language and Test-Driven Development Environment

Unit testing frameworks are nowadays considered a best practice, included inalmost all modern software development processes, to achieve rapid developmentof correct specifications. Knowledge representation and reasoning paradigmssuch as Answer Set Programming (ASP), that have been used in industry-levelapplications, are not an exception. Indeed, the first unit testingspecification language for ASP was proposed in 2011 as a feature of the ASPIDEdevelopment environment. Later, a more portable unit testing language wasincluded in the LANA annotation language. In this paper we revisit bothlanguages and tools for unit testing in ASP. We propose a new unit testspecification language that allows one to inline tests within ASP programs, andwe identify the computational complexity of the tasks associated with checkingthe various program-correctness assertions. Test-case specifications aretransparent to the traditional evaluation, but can be interpreted by a specifictesting tool. Thus, we present a novel environment supporting test drivendevelopment of ASP programs.