Lucene.Net.Index.BaseIndexFileFormatTestCase.TestMergeStability C# (CSharp) Method

        public virtual void TestMergeStability()
        {
            Directory dir = NewDirectory();
            // do not use newMergePolicy that might return a MockMergePolicy that ignores the no-CFS ratio
            MergePolicy mp = NewTieredMergePolicy();
            mp.NoCFSRatio = 0;
            var cfg = (new IndexWriterConfig(TEST_VERSION_CURRENT, new MockAnalyzer(Random()))).SetUseCompoundFile(false).SetMergePolicy(mp);
            using (var w = new RandomIndexWriter(Random(), dir, cfg))
            {
                var numDocs = AtLeast(500);
                for (var i = 0; i < numDocs; ++i)
                {
                    var d = new Document();
                    AddRandomFields(d);
                    w.AddDocument(d);
                }
                w.ForceMerge(1);
                w.Commit();
            }
            IndexReader reader = DirectoryReader.Open(dir);

            Directory dir2 = NewDirectory();
            mp = NewTieredMergePolicy();
            mp.NoCFSRatio = 0;
            cfg = (new IndexWriterConfig(TEST_VERSION_CURRENT, new MockAnalyzer(Random()))).SetUseCompoundFile(false).SetMergePolicy(mp);

            using (var w = new RandomIndexWriter(Random(), dir2, cfg))
            {
                w.AddIndexes(reader);
                w.Commit();
            }

            assertEquals(BytesUsedByExtension(dir), BytesUsedByExtension(dir2));

            reader.Dispose();
            dir.Dispose();
            dir2.Dispose();
        }
    }