ehancement(Bytes32): apply left hand padding in UnmarshalJSON

thor/bytes32.go

@@ -8,7 +8,6 @@ package thor
 import (
 	"encoding/hex"
 	"encoding/json"
-	"errors"
 	"fmt"
 	"strings"
 
@@ -65,14 +64,14 @@ func (b *Bytes32) UnmarshalJSON(data []byte) error {
 
 // ParseBytes32 convert string presented into Bytes32 type
 func ParseBytes32(s string) (Bytes32, error) {
-	if len(s) == 32*2 {
-	} else if len(s) == 32*2+2 {
-		if strings.ToLower(s[:2]) != "0x" {
-			return Bytes32{}, errors.New("invalid prefix")
-		}
-		s = s[2:]
-	} else {
-		return Bytes32{}, errors.New("invalid length")
+	s = strings.TrimPrefix(s, "0x")
+	// if the string is too long, return error
+	if len(s) > 32*2 {
+		return Bytes32{}, fmt.Errorf("invalid length %d", len(s))
+	}
+	// if the string is too short, add padding
+	if len(s) < 32*2 {
+		s = strings.Repeat("0", 32*2-len(s)) + s
 	}
 
 	var b Bytes32

thor/bytes32_test.go

@@ -11,7 +11,7 @@ import (
 	"github.com/stretchr/testify/assert"
 )
 
-func TestMarshalUnmarshal(t *testing.T) {
+func TestBytes32_UnmarshalJSON(t *testing.T) {
 	// Example hex string representing the value 100
 	originalHex := `"0x00000000000000000000000000000000000000000000000000006d6173746572"` // Note the enclosing double quotes for valid JSON string
 
@@ -50,3 +50,12 @@ func TestMarshalUnmarshal(t *testing.T) {
 	assert.NoError(t, err, "Marshaling should not produce an error")
 	assert.Equal(t, `"0x0000000000000000000000000000000000000000000000000000000000000000"`, string(j))
 }
+
+func TestParseBytes32(t *testing.T) {
+	// Example hex string representing the value 100
+	expected := MustParseBytes32("0x0000000000000000000000006d95e6dca01d109882fe1726a2fb9865fa41e7aa")
+	trimmed := "0x6d95e6dca01d109882fe1726a2fb9865fa41e7aa"
+	parsed, err := ParseBytes32(trimmed)
+	assert.NoError(t, err)
+	assert.Equal(t, expected, parsed)
+}