diff --git a/proxy/vmess/aead/kdf_test.go b/proxy/vmess/aead/kdf_test.go
index 89dc7b979..9c011dd94 100644
--- a/proxy/vmess/aead/kdf_test.go
+++ b/proxy/vmess/aead/kdf_test.go
@@ -3,8 +3,9 @@ package aead
 import (
 	"encoding/hex"
 	"fmt"
-	"github.com/stretchr/testify/assert"
 	"testing"
+
+	"github.com/stretchr/testify/assert"
 )
 
 func TestKDFValue(t *testing.T) {