ModelTest provides a way to check for common errors in implementations of http://doc.trolltech.com/4/qabstractitemmodel.html. ModelTest continuously checks a model as it changes, helping to verify the state and catching many common errors the moment they show up such as: --- To Use the model test do the following: 1) Include the pri file at the end of your project pro file using the include() command like so: include(../path/to/dir/modeltest.pri) 2) Then in your source include "modeltest.h" and instantiate ModelTest with your model so the test can live for the lifetime of your model. For example: #include QDirModel *model = new QDirModel(this); new ModelTest(model, this); 3) That is it. When the test finds a problem it will assert. modeltest.cpp contains some hints on how to fix problems that the test finds.