Formalization of Software Testing Criteria using the Z Notation

This paper describes an approach to formalization of criteria of computer systems software testing. A brief review of control-flow criteria is introduced. As a formal language for describing the criteria, the Z notation is selected. Z schemas are presented for definitions of the following criteria: statement coverage, decision coverage, condition coverage, decision/condition coverage, full predicate coverage, modified condition/decision coverage, and multiple condition coverage. This characterization could help in the correct understanding of different types of testing and also the correct application of a desired testing regime.