public void TestRebuildIndex()
        {
            var processor = new DatabaseProcessor <TestEntity>(new DummyDatabase());

            var index = processor.Index;

            Assert.IsNull(index);

            processor.RebuildIndex();
            index = processor.Index;
            Assert.IsNotNull(processor.Index);
            Assert.AreEqual(5, index.Raw.ToList().Count);

            processor.RebuildIndex();
            Assert.AreNotEqual(index, processor.Index);
            Assert.AreEqual(5, index.Raw.ToList().Count);
        }