mergedNodes.add(new Node(11));
mergedNodes.add(new Node(12));
mergedNodes.add(new Node(13));
mergedNodes.add(new Node(14));
model.moveUpMerged(new int[]{1,2,3,4});
assertEquals(5, mergedNodes.size());
assertEquals(11, mergedNodes.get(0).getId());
assertEquals(12, mergedNodes.get(1).getId());
assertEquals(13, mergedNodes.get(2).getId());