Covering both stack and states while testing push-down systems

In this paper we address the problem of generating abstract test cases from a system modelled by a push-down automaton. Existing classical coverage criteria are based either on states, transitions or loops in the automaton. This paper is based on a known theoretical result claiming that the accessible stack configurations in a push-down automaton form a regular language. We propose a new coverage criteria based both on states and on the configurations of the stack. Experimental results on a model of the Shunting Yard Algorithm are also presented.