assignedConstraintsSet.getAssignedConstraints().add(c1);
assignedConstraintsSet.getAssignedConstraints().add(c2);
assignedConstraintsSet.getAssignedConstraints().add(c3);
project.addModelElement(assignedConstraintsSet);
new ClearAssignedConstraintSetCommand(assignedConstraintsSet).runWithoutUnicaseCommand();
assertEquals(0, assignedConstraintsSet.getAssignedConstraints().size());
assertEquals(true, assignedConstraintsSet.isChanged());
}