void createIndex(const DirectoryPtr& dir, bool multiSegment) {
        IndexWriter::unlock(dir);
        IndexWriterPtr w = newLucene<IndexWriter>(dir, newLucene<WhitespaceAnalyzer>(), IndexWriter::MaxFieldLengthLIMITED);

        w->setMergePolicy(newLucene<LogDocMergePolicy>(w));

        for (int32_t i = 0; i < 100; ++i) {
            w->addDocument(createDocument(i, 4));
            if (multiSegment && (i % 10) == 0) {
                w->commit();
            }
        }

        if (!multiSegment) {
            w->optimize();
        }

        w->close();

        IndexReaderPtr r = IndexReader::open(dir, false);
        if (multiSegment) {
            EXPECT_TRUE(r->getSequentialSubReaders().size() > 1);
        } else {
            EXPECT_EQ(r->getSequentialSubReaders().size(), 1);
        }
        r->close();
    }
static IndexWriterPtr newWriter(DirectoryPtr dir, bool create)
{
    IndexWriterPtr writer = newLucene<IndexWriter>(dir, newLucene<WhitespaceAnalyzer>(), create, IndexWriter::MaxFieldLengthUNLIMITED);
    writer->setMergePolicy(newLucene<LogDocMergePolicy>(writer));
    return writer;
}