Lucene.Net.Search.TestCachingWrapperFilter.TestCachingWorks C# (CSharp) Method

        public virtual void TestCachingWorks()
        {
            Directory dir = NewDirectory();
            RandomIndexWriter writer = new RandomIndexWriter(Random(), dir, Similarity, TimeZone);
            writer.Dispose();

            IndexReader reader = SlowCompositeReaderWrapper.Wrap(DirectoryReader.Open(dir));
            AtomicReaderContext context = (AtomicReaderContext)reader.Context;
            MockFilter filter = new MockFilter();
            CachingWrapperFilter cacher = new CachingWrapperFilter(filter);

            // first time, nested filter is called
            DocIdSet strongRef = cacher.GetDocIdSet(context, (context.AtomicReader).LiveDocs);
            Assert.IsTrue(filter.WasCalled(), "first time");

            // make sure no exception if cache is holding the wrong docIdSet
            cacher.GetDocIdSet(context, (context.AtomicReader).LiveDocs);

            // second time, nested filter should not be called
            filter.Clear();
            cacher.GetDocIdSet(context, (context.AtomicReader).LiveDocs);
            Assert.IsFalse(filter.WasCalled(), "second time");

            reader.Dispose();
            dir.Dispose();
        }