You can use qmltestrunner, but you have to register your Python types so that qmlscene and qmltestrunner can use them. To register them you need to use the pyqt5qmlplugin and to get that you need to build PyQt5 from source.
Here is an example of how to structure your code as a plugin. I will take a look but I think the problem with the second commit in that repo is that you have to import the first level first.
So before importing importQEMEL.Objects1.0asQO it needs to have