Creative system test design using object-oriented analysis
Nancy A. Storch · University of North Texas Digital Library (University of North Texas) · 1990
This paper describes actual experiences in designing system level test cases for a large on-line transaction system which keeps track of work orders and payroll for a complex of machine shops. These system tests were designed after the software had been written and the system was about to undergo user acceptance testing. It was an effort independent of the development, intended to improve the overall quality of the delivered system. Although accepted software engineering methods had been used extensively during the development, at the time of these system tests, up-to-date documentation was limited to the user manual. Knowledgeable persons were mostly unavailable, busy with completion of the system. Nevertheless, in this real world situation, the system test cases were needed in a timely fashion. After more conventional tests were designed and run yielding no bugs, a new approach was taken. This involved identifying a major section of the software as an object and then developing a state model for it based on the implementation and availability of certain process information in the database such as: track flags, status, and time stamps. A flow graph was derived from the state transition diagram. Application of basis path testing to a simplified version of the flow graph lead to a meaningful set of test cases which when run found errors. Not only was this testing a success, but the creation of the state model provided valuable documentation for further understanding and maintenance of the software. 7 refs., 3 figs.