fix serlization

Author: tac0turtle

types/serialization.go

@@ -162,6 +162,9 @@ func (h *Header) ToProto() *pb.Header {
 		ChainId:         h.BaseHeader.ChainID,
 		ValidatorHash:   h.ValidatorHash,
 	}
+	if unknown := encodeLegacyUnknownFields(h.Legacy); len(unknown) > 0 {
+		pHeader.ProtoReflect().SetUnknown(unknown)
+	}
 	return pHeader
 }
 
@@ -509,6 +512,28 @@ func decodeLegacyHeaderFields(pHeader *pb.Header) (*LegacyHeaderFields, error) {
 	return &legacy, nil
 }
 
+func encodeLegacyUnknownFields(legacy *LegacyHeaderFields) []byte {
+	if legacy == nil || legacy.IsZero() {
+		return nil
+	}
+
+	var payload []byte
+
+	if len(legacy.LastCommitHash) > 0 {
+		payload = appendBytesField(payload, legacyLastCommitHashField, legacy.LastCommitHash)
+	}
+
+	if len(legacy.ConsensusHash) > 0 {
+		payload = appendBytesField(payload, legacyConsensusHashField, legacy.ConsensusHash)
+	}
+
+	if len(legacy.LastResultsHash) > 0 {
+		payload = appendBytesField(payload, legacyLastResultsHashField, legacy.LastResultsHash)
+	}
+
+	return payload
+}
+
 func appendBytesField(buf []byte, number protowire.Number, value []byte) []byte {
 	buf = protowire.AppendTag(buf, number, protowire.BytesType)
 	buf = protowire.AppendVarint(buf, uint64(len(value)))

types/serialization_test.go

@@ -1,6 +1,7 @@
 package types
 
 import (
+	"bytes"
 	"crypto/rand"
 	"testing"
 	"time"
@@ -355,6 +356,53 @@ func TestHeader_HashFields_NilAndEmpty(t *testing.T) {
 	assert.Nil(t, h2.ValidatorHash)
 }
 
+func TestHeaderMarshalBinary_PreservesLegacyFields(t *testing.T) {
+	t.Parallel()
+
+	header := &Header{
+		Version:    Version{Block: 2, App: 3},
+		BaseHeader: BaseHeader{Height: 42, Time: 123456789, ChainID: "chain-legacy"},
+		LastHeaderHash: []byte{
+			0x01, 0x02, 0x03, 0x04,
+		},
+		DataHash:        []byte{0x05, 0x06, 0x07, 0x08},
+		AppHash:         []byte{0x09, 0x0A, 0x0B, 0x0C},
+		ProposerAddress: []byte{0x0D, 0x0E, 0x0F, 0x10},
+		ValidatorHash:   []byte{0x11, 0x12, 0x13, 0x14},
+		Legacy: &LegacyHeaderFields{
+			LastCommitHash:  bytes.Repeat([]byte{0x21}, 32),
+			ConsensusHash:   bytes.Repeat([]byte{0x22}, 32),
+			LastResultsHash: bytes.Repeat([]byte{0x23}, 32),
+		},
+	}
+
+	unknown := header.ToProto().ProtoReflect().GetUnknown()
+	require.NotEmpty(t, unknown, "legacy fields should be serialized into unknown proto fields")
+
+	raw, err := header.MarshalBinary()
+	require.NoError(t, err)
+	require.NotEmpty(t, raw)
+
+	var decoded Header
+	require.NoError(t, decoded.UnmarshalBinary(raw))
+	require.NotNil(t, decoded.Legacy)
+	require.False(t, decoded.Legacy.IsZero())
+
+	assert.Equal(t, header.Legacy.LastCommitHash, decoded.Legacy.LastCommitHash)
+	assert.Equal(t, header.Legacy.ConsensusHash, decoded.Legacy.ConsensusHash)
+	assert.Equal(t, header.Legacy.LastResultsHash, decoded.Legacy.LastResultsHash)
+
+	origHash := header.Hash()
+	decodedHash := decoded.Hash()
+	require.NotNil(t, origHash)
+	require.NotNil(t, decodedHash)
+	assert.Equal(t, origHash, decodedHash)
+
+	legacyHash, err := header.HashLegacy()
+	require.NoError(t, err)
+	assert.Equal(t, legacyHash, origHash)
+}
+
 // TestProtoConversionConsistency_AllTypes checks that ToProto/FromProto are true inverses for all major types.
 func TestProtoConversionConsistency_AllTypes(t *testing.T) {
 	// Header