Embedded messages are not merged when there is multiple instances of the field in ByteArray

[samulironkko]

It seems that embedded messages are not merged when ByteArray contains multiples instances of the same field. The last value found is accepted like it would be in case of numeric types or strings.

This can be reproduced with the following protobuf

syntax = "proto2";

message SubMessage {
    repeated uint32 repeated_values = 1 [packed = true];
}

message BugMessage {
    optional SubMessage sub_message = 1;
}

And by decoding the following ByteArray that contains 2 instances of SubMessage with 1 repeated value in each instance. The bugMessage should contain SubMessage with 2 repeated values but it only contains the last one.

val bugMessage = BugMessage.ADAPTER.decode(byteArrayOf(10, 3, 10, 1, 1, 10, 3, 10, 1, 1))