protected void addModels(EpoxyModel<?>... modelsToAdd) {
    int initialSize = models.size();
    int numModelsToAdd = modelsToAdd.length;

    ((ModelList) models).ensureCapacity(initialSize + numModelsToAdd);

    pauseModelListNotifications();
    Collections.addAll(models, modelsToAdd);
    resumeModelListNotifications();

    notifyItemRangeInserted(initialSize, numModelsToAdd);
  }
@Test
  public void testAddModelsVarArgs() {
    testAdapter.addModels(new TestModel(), new TestModel());
    verify(observer).onItemRangeInserted(0, 2);
    assertEquals(2, testAdapter.models.size());

    testAdapter.addModels(new TestModel(), new TestModel());
    verify(observer).onItemRangeInserted(2, 2);
    assertEquals(4, testAdapter.models.size());

    checkDifferState();
  }