Two approaches to generate non-equivalent ground terms as test cases for object-oriented software

Software testing is an important technique for improving the reliability and quality of software systems. Object-oriented programming is considered to be the most promising programming methodology. We propose two approaches to generate non-equivalent ground terms as test cases. These approaches are based on the technique of fundamental equivalent pair. The basic idea of these approaches is as follows. Suppose u/sub 1//spl sim/u/sub 2/ is a fundamental equivalent pair, u/sub 2/* is the normal form of u/sub 2/. Suppose further that by changing the values of parameters of constructor contained in u/sub 2/*, or by inserting a basic constructor into u/sub 2/*, we obtain another ground term u/sub 2/', then u/sub 1/ and u/sub 2/' are nonequivalent, and can be used as a test case.