Mage::getConfig()->setModelTestDouble not defined error

[torrtuga]

In my magento project, I have kept the DigitalPianism/TestFramework.. inside the vendor folder.
When I try to run the function setModelTestDouble, it is not able to find the function.
The example given in controller works after adding the DigitalPianism controller file in composer.
But this function present inside Model/Config.php remains undefined when called from a testFunction.