Function SpliceMessages

cpp/src/arrow/ipc/read_write_test.cc:2181–2214

Delimit IPC stream messages and reassemble with the indicated messages included. This way we can remove messages from an IPC stream to test different failure modes or other difficult-to-test behaviors

// included. This way we can remove messages from an IPC stream to test
// different failure modes or other difficult-to-test behaviors
void SpliceMessages(std::shared_ptr<Buffer> stream,
                    const std::vector<int>& included_indices,
                    std::shared_ptr<Buffer>* spliced_stream) {
  ASSERT_OK_AND_ASSIGN(auto out, io::BufferOutputStream::Create(0));

  io::BufferReader buffer_reader(stream);
  std::unique_ptr<MessageReader> message_reader = MessageReader::Open(&buffer_reader);
  std::unique_ptr<Message> msg;

  // Parse and reassemble first two messages in stream
  int message_index = 0;
  while (true) {
    ASSERT_OK_AND_ASSIGN(msg, message_reader->ReadNextMessage());
    if (!msg) {
      break;
    }

    if (std::find(included_indices.begin(), included_indices.end(), message_index++) ==
        included_indices.end()) {
      // Message being dropped, continue
      continue;
    }

    IpcWriteOptions options;
    IpcPayload payload;
    payload.type = msg->type();
    payload.metadata = msg->metadata();
    payload.body_buffers.push_back(msg->body());
    payload.body_length = msg->body()->size();
    int32_t unused_metadata_length = -1;
    ASSERT_OK(ipc::WriteIpcPayload(payload, options, out.get(), &unused_metadata_length));
  }
  ASSERT_OK_AND_ASSIGN(*spliced_stream, out->Finish());
}

TEST(TestRecordBatchStreamReader, NotEnoughDictionaries) {
  // ARROW-6126