@Test
  public void testSplittable() throws SchedulerException {

    List<VM> vms = Arrays.asList(vm1, vm2, vm3);
    Collection<Collection<Node>> parts = new ArrayList<>();
    parts.add(Arrays.asList(n1, n2));
    parts.add(Arrays.asList(n3));
    parts.add(Arrays.asList(n4));

    Among single = new Among(vms, parts);

    /*
    N1 v1 v2
    N2 v3
    ---
    N3 v4
    --
    N4 v5
    */
    FixedNodeSetsPartitioning partitionner = new FixedNodeSetsPartitioning(parts);
    partitionner.setPartitions(parts);
    List<Instance> instances =
        partitionner.split(
            new DefaultParameters(),
            new Instance(mo, Collections.<SatConstraint>emptyList(), new MinMTTR()));

    TIntIntHashMap vmIndex = Instances.makeVMIndex(instances);
    TIntIntHashMap nodeIndex = Instances.makeNodeIndex(instances);
    splitter.split(single, new Instance(mo, new MinMTTR()), instances, vmIndex, nodeIndex);
    Among a = (Among) instances.get(0).getSatConstraints().iterator().next();
    Assert.assertEquals(a.getGroupsOfNodes().size(), 1);
    Assert.assertEquals(a.getInvolvedNodes(), Arrays.asList(n1, n2));
    for (Instance i : instances) {
      System.out.println(i.getSatConstraints());
    }
  }