Checking Sanity of Software Requirements

In the last decade it became a common practice to formalise software requirements to improve the clarity of users’ expectations. In this work we build on the fact that functional requirements can be expressed in temporal logic and we propose new techniques that automatically detect flaws and suggest improvements of given requirements. Specifically, we describe and experimentally evaluate new approaches to consistency and vacuity checking that identify all inconsistencies and pinpoint their exact source (the smallest inconsistent set). To complete the sanity checking we also deliver a novel semi-automatic completeness evaluation that can assess the coverage of user requirements and suggest missing properties the user might have wanted to formulate. The usefulness of our completeness evaluation is demonstrated in a case study of an aeroplane control system.