sizeOfMessage function

int sizeOfMessage(Map<String, Object?> message, List<Map<String, Object?>> descriptor)

Calculates the encoded byte size of message without producing output.

This is used when encoding length-prefixed submessages: the parent needs to know the byte length before writing the length prefix.

Implementation

int sizeOfMessage(
  Map<String, Object?> message,
  List<Map<String, Object?>> descriptor,
) {
  // The simplest correct implementation: marshal to bytes and measure length.
  // This avoids duplicating all the size-calculation logic for every type.
  return marshal(message, descriptor).length;
}