Non-Deterministic Timed Pushdown Automata-Based Testing Evaluated by Mutation

This paper is about conformance testing of non deterministic timed pushdown automata with inputs and outputs (TPAIO), that specify both stack and clock constraints. It proposes a novel off-line test generation method from this model. The first step computes a deterministic timed pushdown tester with inputs and outputs (DTPTIO): a TPAIO which approximates the initial TPAIO with only one clock. Then we compute from the DTPTIO a finite reachability automaton (RA), whose transitions are related to DTPTIO paths satisfying the stack constraints. This computation takes the DTPTIO transitions as a coverage criterion. The RA transitions, thus the DTPTIO paths, are used for generating test cases that aim at covering the reachable locations and transitions of the TPAIO. The test cases are in the shape of trees equipped with verdicts. Last, we propose a mutation testing method from non-deterministic TPAIO to evaluate the efficiency of our method.