How to unit test diagram related operations ?

Hi everyone,
I’m currently trying to test (with JUnit) my viewpoint code. For example, I want to test below method.
However this test will fail because ExecutionManager is null has no Sirius session is loaded and no diagram is open. Searching Eclipse Sirius forum I found this
topic advising to make test class extend SiriusDiagramTestCase. So I installed Sirius test suite and did so. However though I understand that setup and genericSetup method are the keys, I dont know how to properly use them (mine just hang up indefinitly) and I searched a bit in Sirius tests but could not find suitable code.
Can someone point me in the right direction ? Thanks in advance for any help.