Testing strategies for form-based visual programs

Form based visual programming languages, which include electronic spreadsheets and a variety of research systems, have had a substantial impact on end user computing. Research shows that form based visual programs often contain faults, and that their creators often have unwarranted confidence in the reliability of their programs. Despite this evidence, we find no discussion in the research literature of techniques for testing or assessing the reliability of form based visual programs. The paper addresses this lack. We describe differences between the form based and imperative programming paradigms, and discuss effects these differences have on strategies for testing form based programs. We then present several test adequacy criteria for form based programs, and illustrate their application. We show that an analogue to the traditional "all-uses" dataflow test adequacy criterion is well suited for code based testing of form based visual programs: it provides important error detection ability, and can be applied more easily to form based programs than to imperative programs.