state: drop compatibility code for NEOBalance

A part of #3454.

Signed-off-by: Roman Khimov <roman@nspcc.ru>

ROADMAP.md

@@ -25,13 +25,6 @@ APIs/commands/configurations will be removed and here is a list of scheduled
 breaking changes. Consider changing your code/scripts/configurations if you're
 using anything mentioned here.
 
-## `NEOBalance` from stack item
- 
-We check struct items count before convert LastGasPerVote to let RPC client be compatible with
-old versions.
-
-Removal of this compatiblility code is scheduled for Jun-Jul 2024.
-
 ## `serv_node_version` Prometheus gauge metric
 
 This metric is replaced by the new `neogo_version` and `server_id` Prometheus gauge

pkg/core/state/native_state.go

@@ -133,7 +133,7 @@ func (s *NEOBalance) ToStackItem() (stackitem.Item, error) {
 // FromStackItem converts stackitem.Item to NEOBalance.
 func (s *NEOBalance) FromStackItem(item stackitem.Item) error {
 	structItem, ok := item.Value().([]stackitem.Item)
-	if !ok || len(structItem) < 3 {
+	if !ok || len(structItem) < 4 {
 		return errors.New("invalid stackitem length")
 	}
 	balance, err := structItem[0].TryInteger()
@@ -159,12 +159,10 @@ func (s *NEOBalance) FromStackItem(item stackitem.Item) error {
 		}
 		s.VoteTo = pub
 	}
-	if len(structItem) >= 4 {
-		lastGasPerVote, err := structItem[3].TryInteger()
-		if err != nil {
-			return fmt.Errorf("invalid last vote reward per neo stackitem: %w", err)
-		}
-		s.LastGasPerVote = *lastGasPerVote
+	lastGasPerVote, err := structItem[3].TryInteger()
+	if err != nil {
+		return fmt.Errorf("invalid last vote reward per neo stackitem: %w", err)
 	}
+	s.LastGasPerVote = *lastGasPerVote
 	return nil
 }

pkg/rpcclient/neo/neo_test.go

@@ -105,6 +105,7 @@ func TestGetAccountState(t *testing.T) {
 				stackitem.Make(100500),
 				stackitem.Make(42),
 				stackitem.Null{},
+				stackitem.Make(0),
 			}),
 		},
 	}