DocumentPtr newDoc() {
     DocumentPtr d = newLucene<Document>();
     double boost = nextNorm();
     for (int32_t i = 0; i < 10; ++i) {
         FieldPtr f = newLucene<Field>(L"f" + StringUtils::toString(i), L"v" + StringUtils::toString(i), Field::STORE_NO, Field::INDEX_NOT_ANALYZED);
         f->setBoost(boost);
         d->add(f);
     }
     return d;
 }