    @Test
    public void testAddItemAtTheBegining() throws Exception {

        mDetector.newData(mAdapter, ImmutableList.of(new Cat(2, "two")), false);
        reset(mAdapter);
        mDetector.newData(mAdapter, ImmutableList.of(new Cat(1, "one"), new Cat(2, "two")), false);
        verify(mAdapter).notifyItemRangeInserted(0, 1);
    }