Coverage Analysis of Net Inscriptions in Coloured Petri Net Models

TL;DR

This paper introduces a novel coverage analysis method for Coloured Petri Nets, focusing on the validation of net inscriptions like arc expressions and guards using MC/DC coverage, implemented in CPN Tools.

Contribution

It presents an approach linking coverage analysis from programming languages to CPN net inscriptions, with an implementation for MC/DC coverage assessment.

Findings

Effective coverage analysis of net inscriptions in CPNs.

Implementation of an MC/DC coverage tool in CPN Tools.

Evaluation on four large public CPN models.

Abstract

High-level Petri net such as Coloured Petri Nets (CPNs) are characterised by the combination of Petri nets and a high-level programming language. In the context of CPNs and CPN Tools, the inscriptions (e.g., arc expressions and guards) are specified using Standard ML (SML). The application of simulation and state space exploration (SSE) for validating CPN models traditionally focuses on behavioural properties related to net structure, i.e., places and transitions. This means that the net inscriptions are only implicitly validated, and the extent to which these have been covered is not made explicit. The contribution of this paper is an approach that establishes a link between coverage analysis known from programming languages and net inscriptions of CPN models. Specifically, we consider Modified Condition/Decision Coverage (MC/DC) which generalises branch coverage of SML decisions. We have implemented our approach in a library for CPN Tools comprised of an annotation and instrumentation mechanism that transparently intercept and collect evaluations of Boolean conditions, and a post-processing tool that determines whether each decision is MC/DC-covered by a set of models executions (runs). We evaluate our approach on four larger public-available CPN models.