Monadic Sequence Testing and Explicit Test-Refinements

Abstract

We present an abstract framework for sequence testing that is implemented in Isabelle/HOL-TestGen. Our framework is based on the theory of state-exception monads, explicitly modelled in HOL, and can cope with typed input and output, interleaving executions including abort, and synchronisation. The framework is particularly geared towards symbolic execution and has proven effective in several large case-studies involving system models based on large (or infinite) state. On this basis, we rephrase the concept of test-refinements for inclusion, deadlock and IOCO-like tests, together with a formal theory of its relation to traditional, IO-automata based notions.

A Symbolic Operational Semantics for TESL

“…1. we assume the monitor has an access to the SUT interfaces (see Figure 1) via a driver that abstracts observations into tagged events on clocks; 2. we assume that the computing time of the driver and of Heron can be neglected with regard to the execution time of the SUT, and 3. we assume that the system is output deterministic; i.e after an initialization of the SUT by the tester, it is possible to track the state of the SUT by only observing its inputs and outputs [8].…”