UNA Based Iterative Test Data Generation and Its Evaluation

A number of approaches have been proposed to automatically generate test data to traverse a given path in a program. In this paper, we present a program execution based approach to generate test data for a given path. The technique derives a desired input for a test path by iteratively reening an arbitrarily chosen input. A set of linear constraints on the increments to the input are derived to reene the input. We solve this constraint set using a Uniied Numerical Approach (UNA) developed in this paper. Our technique can generate both integer and oating point inputs as well as handle arrays and loops. We determine a basis set of paths for a program and use our technique to generate test data for this set. We implemented and experimentally evaluated our technique. We present results of generating input for scientiic programs. The experimental results show that the technique is eeective in that it generates input for most of the paths in the basis sets and also eeciently detects linear infeasible paths. Our experiments also show that our technique is eecient in the number of iterations required to generate test data. The time performance shows that it provides a practical method to automatically generate test data for scientiic programs.