From fa411df3779023f0d1282ddf609fe11c370874f5 Mon Sep 17 00:00:00 2001
From: Grzegorz Prusak <pompon.pompon@gmail.com>
Date: Tue, 24 Mar 2026 20:13:09 +0100
Subject: [PATCH] fixed ValidatorInfo json encoding (#3114)

There were 2 issues:
* for backward compatibility with CosmJS, PubKey needs to be a 0 key in
case of non-validator node.
* decoding was broken altogether, because it always returned the zero
value of ValidatorInfo

(cherry picked from commit be7fb0279bfe22d38ce584cb130034983eead15d)
---
 sei-tendermint/rpc/coretypes/responses.go     | 32 +++++++++++--------
 .../rpc/coretypes/responses_test.go           | 27 ++++++++++++++++
 2 files changed, 45 insertions(+), 14 deletions(-)

diff --git a/sei-tendermint/rpc/coretypes/responses.go b/sei-tendermint/rpc/coretypes/responses.go
index 4351d04069..9222eadf5b 100644
--- a/sei-tendermint/rpc/coretypes/responses.go
+++ b/sei-tendermint/rpc/coretypes/responses.go
@@ -129,6 +129,7 @@ type ValidatorInfo struct {
 	VotingPower int64
 }
 
+// CosmJS compatible response, which contains a public key = 0 in case of non-validator nodes.
 type validatorInfoJSON struct {
 	Address     bytes.HexBytes  `json:"address"`
 	PubKey      json.RawMessage `json:"pub_key"`
@@ -136,25 +137,28 @@ type validatorInfoJSON struct {
 }
 
 func (v ValidatorInfo) MarshalJSON() ([]byte, error) {
-	j := validatorInfoJSON{VotingPower: v.VotingPower}
-	if k, ok := v.PubKey.Get(); ok {
-		pk, err := jsontypes.Marshal(k)
-		if err != nil {
-			return nil, err
-		}
-		j.PubKey = pk
-		j.Address = k.Address()
+	k := v.PubKey.Or(crypto.PubKey{})
+	pk, err := jsontypes.Marshal(k)
+	if err != nil {
+		return nil, err
 	}
-	return json.Marshal(j)
+	return json.Marshal(validatorInfoJSON{
+		VotingPower: v.VotingPower,
+		PubKey:      pk,
+		Address:     k.Address(),
+	})
 }
 
 func (v *ValidatorInfo) UnmarshalJSON(data []byte) error {
 	var val validatorInfoJSON
-	if len(val.PubKey) != 0 {
-		var pk crypto.PubKey
-		if err := jsontypes.Unmarshal(val.PubKey, &pk); err != nil {
-			return err
-		}
+	if err := json.Unmarshal(data, &val); err != nil {
+		return err
+	}
+	var pk crypto.PubKey
+	if err := jsontypes.Unmarshal(val.PubKey, &pk); err != nil {
+		return err
+	}
+	if pk != (crypto.PubKey{}) {
 		v.PubKey = utils.Some(pk)
 	}
 	v.VotingPower = val.VotingPower
diff --git a/sei-tendermint/rpc/coretypes/responses_test.go b/sei-tendermint/rpc/coretypes/responses_test.go
index 91e7bc14e1..3fedc4b260 100644
--- a/sei-tendermint/rpc/coretypes/responses_test.go
+++ b/sei-tendermint/rpc/coretypes/responses_test.go
@@ -12,6 +12,9 @@ import (
 	"github.com/stretchr/testify/require"
 
 	abci "github.com/sei-protocol/sei-chain/sei-tendermint/abci/types"
+	"github.com/sei-protocol/sei-chain/sei-tendermint/crypto"
+	"github.com/sei-protocol/sei-chain/sei-tendermint/crypto/ed25519"
+	"github.com/sei-protocol/sei-chain/sei-tendermint/libs/utils"
 	pbcrypto "github.com/sei-protocol/sei-chain/sei-tendermint/proto/tendermint/crypto"
 	"github.com/sei-protocol/sei-chain/sei-tendermint/types"
 )
@@ -91,3 +94,27 @@ func TestResultBlockResults_regression8583(t *testing.T) {
 		t.Errorf("Unmarshaled result (-want, +got):\n%s", diff)
 	}
 }
+
+func TestValidatorInfoJSONReencoding(t *testing.T) {
+	cases := map[string]ValidatorInfo{
+		"non-validator": {
+			PubKey:      utils.None[crypto.PubKey](),
+			VotingPower: 0,
+		},
+		"validator": {
+			PubKey:      utils.Some(ed25519.TestSecretKey([]byte("validator-info-json")).Public()),
+			VotingPower: 123,
+		},
+	}
+
+	for name, want := range cases {
+		t.Run(name, func(t *testing.T) {
+			raw, err := json.Marshal(want)
+			require.NoError(t, err)
+
+			var got ValidatorInfo
+			require.NoError(t, json.Unmarshal(raw, &got))
+			require.NoError(t, utils.TestDiff(want, got))
+		})
+	}
+}