Reverse Generation and Refactoring of Fit Acceptance Tests for Legacy Code

The Fit framework is a well established tool for creating early and automated acceptance tests. Available Eclipse plug-ins like FITpro support for new requirements and new code writing of test data and creation of test stubs quite well. In our project we faced the problem, that a large legacy system should undergo a major refactoring. Before this, acceptance tests had to be added to the system to ensure equivalent program behavior before and after the changes. Writing acceptance tests manually for existing code is very laborious, cumbersome and very costly. However reverse generation of fit tests based on legacy code is not foreseen in the current Fit framework, and there are no other tools available to do so. So we decided to develop a tool which allows generation of the complete Fit test code and test specification based on existing code. The tool also includes automatic refactoring of test data when refactoring production code and vice versa, when changing the Fit test specification, it also updates production code accordingly. This reduces the maintenance effort of Fit tests in general and we hope, this will help to spread the usage of Fit for acceptance and integration testing even more.