Towards a statistical approach to testing object-oriented programs

Statistical testing is based on a probabilistic generation of test data: structural or functional criteria serve as guides for defining an input profile and a test size. Previous work has confirmed the high fault revealing power of this approach for procedural programs; it is now investigated for object-oriented programs. A method for incremental statistical testing is defined at the cluster level, based on the class inheritance hierarchy. Starting from the root class of the program, descendant class(es) are gradually added and test data are designed for (i) structural testing of newly defined features and, (ii) regression testing of inherited features. The feasibility of the method is exemplified by a small case study (a Travel Agency) implemented in Eiffel.