Function TweakValidityBit

cpp/src/arrow/testing/gtest_util.cc:571–582

}

std::shared_ptr<Array> TweakValidityBit(const std::shared_ptr<Array>& array,
                                        int64_t index, bool validity) {
  auto data = array->data()->Copy();
  if (data->buffers[0] == nullptr) {
    data->buffers[0] = *AllocateBitmap(data->length);
    bit_util::SetBitsTo(data->buffers[0]->mutable_data(), 0, data->length, true);
  }
  bit_util::SetBitTo(data->buffers[0]->mutable_data(), index, validity);
  data->null_count = kUnknownNullCount;
  // Need to return a new array, because Array caches the null bitmap pointer
  return MakeArray(data);
}

// XXX create a testing/io.{h,cc}?