Chapter 14 - The Role of Unit Tests in the Software Process

Abstract

This chapter describes the role of unit tests in a software engineering environment. It shows how and at what cost automated unit tests based on the test-first approach can be integrated into a documented software process, and to what extent they are already integrated in commercial software engineering processes. The numbers of influences that drive the decision for one process or another methodology are innumerable. Heavyweight and document-oriented processes are less flexible than agile processes [Fowler01], and XP belongs to the latter. Small project teams developing software for a single customer often regard such software engineering processes as outdated. Different process structures, such as sequential, incremental, and evolutionary structures are introduced and then costs and benefits in relation to the respective structure are studied. Finally, the use of automated unit tests in popular commercial process models is discussed. Developing and introducing a different work method into a large development department usually means high investments. For this reason, a cost-benefit analysis should be conducted before decisions are made about the use of automated unit tests.