The purpose of this work is to evaluate, by means of a case study, our formal testing method for object-oriented software. For this purpose we propose the development of an object-oriented application of realistic size, addressing all the phases of the software life-cycle: requirements, analysis, design, formal description, implementation and testing. Analysis and design are performed with the Fusion method, formal description with the CO-OPN language, implementation with Ada 95 and test selection with our testing method. The description of the production cell case study and Fusion models are presented in technical report EPFL-DI 98/298. This report presents the formal description and testing phase.