kvlistformat: fix the issue with display marshalled value for non string type

internal/serialize/keyvalues.go

@@ -145,7 +145,7 @@ func KVListFormat(b *bytes.Buffer, keysAndValues ...interface{}) {
 			case string:
 				writeStringValue(b, true, value)
 			default:
-				writeStringValue(b, false, fmt.Sprintf("%+v", v))
+				writeStringValue(b, false, fmt.Sprintf("%+v", value))
 			}
 		case []byte:
 			// In https://github.com/kubernetes/klog/pull/237 it was decided

internal/serialize/keyvalues_test.go

@@ -39,13 +39,42 @@ func (p point) String() string {
 	return fmt.Sprintf("x=%d, y=%d", p.x, p.y)
 }
 
+type dummyStruct struct {
+	key   string
+	value string
+}
+
+func (d *dummyStruct) MarshalLog() interface{} {
+	return map[string]string{
+		"key-data":   d.key,
+		"value-data": d.value,
+	}
+}
+
+type dummyStructWithStringMarshal struct {
+	key   string
+	value string
+}
+
+func (d *dummyStructWithStringMarshal) MarshalLog() interface{} {
+	return fmt.Sprintf("%s=%s", d.key, d.value)
+}
+
 // Test that kvListFormat works as advertised.
 func TestKvListFormat(t *testing.T) {
 	var emptyPoint *point
 	var testKVList = []struct {
 		keysValues []interface{}
 		want       string
 	}{
+		{
+			keysValues: []interface{}{"data", &dummyStruct{key: "test", value: "info"}},
+			want:       " data=map[key-data:test value-data:info]",
+		},
+		{
+			keysValues: []interface{}{"data", &dummyStructWithStringMarshal{key: "test", value: "info"}},
+			want:       ` data="test=info"`,
+		},
 		{
 			keysValues: []interface{}{"pod", "kubedns"},
 			want:       " pod=\"kubedns\"",