Using mutual information to test from Finite State Machines: Test suite generation

Abstract

Mutual Information is an information theoretic measure designed to quantify the amount of similarity between two random variables ranging over two sets. In recent work we have use it as a base for a measure, called Biased Mutual Information, to guide the selection of a test suite among different possibilities. In this paper, we adapt this concept and show how it can be used to address the problem of generating a test suite with high fault finding capability, in a black-box scenario and following a maximise diversity approach. Additionally, we present a new Grammar-Guided Genetic Programming Algorithm that uses Biased Mutual Information to guide the generation of such test suites. Our experimental results clearly show the potential value of our measure when used to generate test suites. Moreover, they show that our measure is better in guiding test generation than current state-of-the-art measures, like Test Set Diameter (TSDm) measures. Additionally, we compared our proposal with classical completeness-oriented methods, like the H-Method and the Transition Tour method, and found that our proposal produces smaller test suites with high enough fault finding capability. Therefore, our methodology is preferable in an scenario where a compromise is necessary between fault detection and execution time.