Automated testing system

An apparatus for use with a computer system, including a central processing unit, for testing an application program comprised of a plurality of components, each of the plurality of components operating on parameter data and producing output values therefrom, the apparatus comprising:

• (a) storage means controlled by the central processing unit and cooperating with the computer system to store the application program;
• (b) means for storing predicate rules for detecting invalid data, the predicate rules comprising precondition rules for detecting semantically invalid parameter data and postcondition rules for detecting invalid output values generated by one of the plurality of components;
• (c) means responsive to the stored application program and to the stored predicate rules for compiling the predicate rules and the application program to generate an executable program module, an executable precondition module and an executable postcondition module in a common library;
• (d) means for generating a pool of syntactically correct parameter data from a lexical analysis of the application;
• (e) means responsive to the pool of parameter data for applying the parameter data to the precondition module to remove semantically invalid parameter data therefrom and for applying parameter data remaining in the pool of parameter data to each of the plurality of components to generate output values;
• and
• (f) means controlled by the central processing unit and responsive to the output values for applying the output values to the postcondition module to detect invalid output data.