diff --git a/pkg/structure/stringx/string_test.go b/pkg/structure/stringx/string_test.go
index 978028b..d9e53cb 100644
--- a/pkg/structure/stringx/string_test.go
+++ b/pkg/structure/stringx/string_test.go
@@ -1,9 +1,10 @@
 package stringx
 
 import (
+	"testing"
+
 	"gitee.com/timedb/wheatCache/pkg/structure"
 	"github.com/stretchr/testify/require"
-	"testing"
 )
 
 func TestStringSingle_Set(t *testing.T) {
@@ -80,3 +81,11 @@ func TestStringSingle_Getbit(t *testing.T) {
 	require.NoError(t, err)
 	require.Equal(t, res, false)
 }
+
+func TestStringSingle_Getrange(t *testing.T) {
+	s := NewStringSingle()
+	s.Set("abcdefg")
+	k, err := s.Getrange(0, 3)
+	require.NoError(t, err)
+	require.Equal(t, "abc", k)
+}