@Test(expected = WrongReferenceAttributeValueException.class)
public void testUnixGroupNameSet() throws Exception {

	System.out.println("testUnixGroupNameSet()");
	Set<String> set = new HashSet<>();
	set.add(attributeToCheck.getNamespace());
	when(sess.getPerunBl().getModulesUtilsBl().getSetOfGroupNameNamespacesWhereFacilitiesHasTheSameGIDNamespace(sess, new ArrayList<>(), attributeToCheck)).thenReturn(set);
	reqAttribute.setValue("value");
	classInstance.checkAttributeSemantics(sess, resource, attributeToCheck);
}