Abstract

Inheritance is an important feature of the OO approach that allows a designer to easily build a new derived class that extends the functionality of an existing base class. In order to exploit the full potential of inheritance to build systems incrementally, the designer must also be able to test and reason about the behavior of the derived class in an incremental manner. In this paper we develop a specification-based technique for testing both base and derived classes, with the specification and tests for the derived class being obtained incrementally from those of the base class. Using our approach, given the concrete specification of a method m() of a class, we can mechanically generate a simple test method for m(). We show how our approach can be integrated with a standard testing framework. We illustrate the approach by applying it to a simple example.

Citations