encodeBytes function

List<int> encodeBytes(List<int> buffer, List<int> data)

Append length-delimited raw bytes to buffer.

Format: varint(length) + raw bytes. Reference: https://protobuf.dev/programming-guides/encoding/#length-types

Implementation

List<int> encodeBytes(List<int> buffer, List<int> data) {
  encodeVarint(buffer, data.length);
  // Append per-item (NOT buffer.addAll(data)): addAll encodes to the
  // non-mutating `list_concat` on the C++/TS targets, which returns a NEW list
  // that callers relying on in-place mutation (marshal discards the return
  // value) silently drop — corrupting every string/bytes/packed/message field.
  // `.add` compiles to an in-place `list_push` on the shared buffer, so the
  // appended bytes are visible to the caller. See .claude/rules/dart.md.
  for (final b in data) {
    buffer.add(b);
  }
  return buffer;
}