From c3c3d03551f758fae208770b19f2cfc08a37a5af Mon Sep 17 00:00:00 2001
From: Daniel Liu <139250065@qq.com>
Date: Mon, 3 Nov 2025 18:54:14 +0800
Subject: [PATCH] common: fix gas fee mismatch before TIPTRC21Fee, close XFN-51
 (#1636)

---
 common/gas.go                             | 2 ++
 contracts/trc21issuer/trc21issuer_test.go | 6 ++++++
 2 files changed, 8 insertions(+)

diff --git a/common/gas.go b/common/gas.go
index 1e40721b14..7f1135ceea 100644
--- a/common/gas.go
+++ b/common/gas.go
@@ -13,6 +13,8 @@ func GetGasFee(blockNumber, gas uint64) *big.Int {
 		fee = fee.Mul(fee, GasPrice50x)
 	} else if blockNumber > TIPTRC21Fee.Uint64() {
 		fee = fee.Mul(fee, TRC21GasPrice)
+	} else {
+		fee = fee.Mul(fee, TRC21GasPriceBefore)
 	}
 
 	return fee
diff --git a/contracts/trc21issuer/trc21issuer_test.go b/contracts/trc21issuer/trc21issuer_test.go
index 19e3dde595..42b750cb0f 100644
--- a/contracts/trc21issuer/trc21issuer_test.go
+++ b/contracts/trc21issuer/trc21issuer_test.go
@@ -30,6 +30,12 @@ var (
 )
 
 func TestFeeTxWithTRC21Token(t *testing.T) {
+	oldTRC21GasPriceBefore := new(big.Int).Set(common.TIPTRC21Fee)
+	defer func() {
+		common.TIPTRC21Fee = oldTRC21GasPriceBefore
+	}()
+	common.TRC21GasPriceBefore = big.NewInt(1)
+
 	// init genesis
 	contractBackend := backends.NewXDCSimulatedBackend(
 		types.GenesisAlloc{