AUTOMATED TESTING SYSTEM

A method and apparatus for testing software programs systematically explores valid call sequences using a collection of data with a software program comprising a collection of subroutine components. Instead of writing unit tests, the subject invention provides tools to develop precondition rules which systematically remove from the data collection, data which is syntactically incorrect for proper operation with the software program and then data which is semantically incorrect for the software program. The resulting reduced data collection is applied to the collection of components to generate output values which are then checked against postcondition rules to verify that the software program operated correctly. The test method and apparatus are implemented in object-oriented technology to allow test engineers to quickly and easily develop invariants, precondition rules and postcondition rules which are used to test the software program.