Function fuzzFlatPrimitiveImpl

bolt/vector/fuzzer/VectorFuzzer.cpp:672–890

template <TypeKind kind>
void fuzzFlatPrimitiveImpl(
    const VectorPtr& vector,
    FuzzerGenerator& rng,
    const VectorFuzzer::Options& opts) {
  using TFlat = typename KindToFlatVector<kind>::type;
  using TCpp = typename TypeTraits<kind>::NativeType;

  auto flatVector = vector->as<TFlat>();
  std::string strBuf;

  // Randomly generate a reusable part (substring) to prepare for incremental
  // string generation.
  size_t reusablePartLength = opts.enableStringIncrementalGeneration
      ? rand<uint32_t>(rng) % opts.stringLength
      : 0;
  std::u32string reusablePartBuffer;
  reusablePartBuffer.resize(reusablePartLength);
  fillBuffer(reusablePartBuffer, 0, reusablePartLength, rng, opts);

  for (size_t i = 0; i < vector->size(); ++i) {
    if constexpr (std::is_same_v<TCpp, StringView>) {
      if (opts.genTimestampString) {
        auto str =
            std::to_string(randTimestamp(rng, opts).toNanos()).substr(0, 10);
        for (int j = 0; j < rand<uint>(rng) % 24; ++j) {
          str += fmt::format(
              ",{}",
              std::to_string(randTimestamp(rng, opts).toNanos()).substr(0, 10));
        }
        flatVector->set(i, StringView(str));
      } else {
        if (i == 0) {
          clearInputCorpus(inputCorpus<std::string>);
        }

        bool selectFromInputCorpus = rand<bool>(rng);
        size_t stringInputCorpusSize = inputCorpus<std::string>.size();
        if (opts.enableDuplicates && selectFromInputCorpus &&
            stringInputCorpusSize > 0) {
          // Reuse an existing string from the corpus as the next input.
          auto index = rand<size_t>(rng) % stringInputCorpusSize;
          auto selectedStringFromCorpus =
              getInputFromInputCorpus(inputCorpus<std::string>, index);
          flatVector->set(i, StringView(selectedStringFromCorpus));
        } else {
          // Generate a new string as the next input.
          bool doStringIncrementalGeneration =
              opts.enableStringIncrementalGeneration ? rand<bool>(rng) : false;

          auto newString = randString(
              rng,
              opts,
              strBuf,
              doStringIncrementalGeneration,
              reusablePartBuffer,
              reusablePartLength);

          std::string newStringCopy(newString.data(), newString.size());