From 741492cc75306ea704537b28faffe37a71e20a59 Mon Sep 17 00:00:00 2001
From: Mantre <mantre@protonmail.com>
Date: Thu, 26 Oct 2023 16:36:24 +0800
Subject: [PATCH] fix(consensus): not increase the vote-box power on duplicated
 votes (#785)

---
 consensus/voteset/vote_box.go      |  6 ++++--
 consensus/voteset/vote_box_test.go | 28 ++++++++++++++++++++++++++++
 2 files changed, 32 insertions(+), 2 deletions(-)
 create mode 100644 consensus/voteset/vote_box_test.go

diff --git a/consensus/voteset/vote_box.go b/consensus/voteset/vote_box.go
index 89359ddf2..f789fad19 100644
--- a/consensus/voteset/vote_box.go
+++ b/consensus/voteset/vote_box.go
@@ -18,6 +18,8 @@ func newVoteBox() *voteBox {
 }
 
 func (vs *voteBox) addVote(vote *vote.Vote, power int64) {
-	vs.votes[vote.Signer()] = vote
-	vs.votedPower += power
+	if vs.votes[vote.Signer()] == nil {
+		vs.votes[vote.Signer()] = vote
+		vs.votedPower += power
+	}
 }
diff --git a/consensus/voteset/vote_box_test.go b/consensus/voteset/vote_box_test.go
new file mode 100644
index 000000000..33d7ad301
--- /dev/null
+++ b/consensus/voteset/vote_box_test.go
@@ -0,0 +1,28 @@
+package voteset
+
+import (
+	"testing"
+
+	"github.com/pactus-project/pactus/types/vote"
+	"github.com/pactus-project/pactus/util/testsuite"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestDuplicateVote(t *testing.T) {
+	ts := testsuite.NewTestSuite(t)
+
+	hash := ts.RandHash()
+	height := ts.RandHeight()
+	round := ts.RandRound()
+	signer := ts.RandValAddress()
+	power := ts.RandInt64(1000)
+
+	v := vote.NewPrepareVote(hash, height, round, signer)
+
+	vb := newVoteBox()
+
+	vb.addVote(v, power)
+	vb.addVote(v, power)
+
+	assert.Equal(t, vb.votedPower, power)
+}