Transition coverage based test case generation from state chart diagram

Abstract

State-based testing is a challenging area in the software testing field. This paper proposes a set of algorithms to generate test cases from a state chart diagram based on various coverage criteria. The objective is to find various types of state-based faults by covering states and transitions of an object. First, the state chart diagram is transformed into an intermediate graph, State Chart Intermediate Graph (SCIG). Then, for a given coverage criteria, traversing method is applied on SCIG to generate test cases. Different trees from SCIG based on various coverage criteria are extracted for test case generation. Various coverage criteria such as All Transition (AT), Round Trip Path (RTP) and All Transition Pair (ATP) are considered. We introduce algorithms for two most efficient state-based criteria, RTP and ATP. Two case studies, Stack Operation and Vending Machine Automation system, are discussed throughout the paper. We experimentally observed that (i) AT consumes the most test resources (ii) ATP can’t achieve 100% transition coverage (iii) test cases generated based on RTP is efficient, and it overcomes the transition explosion problem of AT. This analysis is beneficial in the area of semi-automatic test case generation in model-based testing.