Nullable for HashIndexState and TransactionState (#3801)

* Fix interop serialization

* Clean

* Ensure is valid

* Clean

* Fix new class

* Clean HashIndexState

* Update src/Neo/SmartContract/Native/HashIndexState.cs

* TransactionState nullable

* Clean

* fix

* Revert storageItem changes

* optimize

* Revert some changes

---------

Co-authored-by: Vitor Nazário Coelho <vncoelho@gmail.com>
Co-authored-by: Christopher Schuchardt <cschuchardt88@gmail.com>

Author: 3 people

src/Neo.CLI/CLI/MainService.Blockchain.cs

@@ -119,15 +119,15 @@ public void OnShowTransactionCommand(UInt256 hash)
             {
                 var tx = NativeContract.Ledger.GetTransactionState(NeoSystem.StoreView, hash);
 
-                if (tx is null)
+                if (tx?.Transaction is null)
                 {
                     ConsoleHelper.Error($"Transaction {hash} doesn't exist.");
                     return;
                 }
 
                 var block = NativeContract.Ledger.GetHeader(NeoSystem.StoreView, tx.BlockIndex);
 
-                DateTime transactionDatetime = new DateTime(1970, 1, 1, 0, 0, 0, 0, DateTimeKind.Utc);
+                var transactionDatetime = new DateTime(1970, 1, 1, 0, 0, 0, 0, DateTimeKind.Utc);
                 transactionDatetime = transactionDatetime.AddMilliseconds(block.Timestamp).ToLocalTime();
 
                 ConsoleHelper.Info("", "-------------", "Transaction", "-------------");

src/Neo/SmartContract/Native/HashIndexState.cs

@@ -9,6 +9,8 @@
 // Redistribution and use in source and binary forms with or without
 // modifications are permitted.
 
+#nullable enable
+
 using Neo.Extensions;
 using Neo.VM;
 using Neo.VM.Types;
@@ -17,12 +19,12 @@ namespace Neo.SmartContract.Native
 {
     class HashIndexState : IInteroperable
     {
-        public UInt256 Hash;
-        public uint Index;
+        public UInt256 Hash { get; set; } = UInt256.Zero;
+        public uint Index { get; set; }
 
         void IInteroperable.FromStackItem(StackItem stackItem)
         {
-            Struct @struct = (Struct)stackItem;
+            var @struct = (Struct)stackItem;
             Hash = new UInt256(@struct[0].GetSpan());
             Index = (uint)@struct[1].GetInteger();
         }
@@ -33,3 +35,5 @@ StackItem IInteroperable.ToStackItem(IReferenceCounter referenceCounter)
         }
     }
 }
+
+#nullable disable

src/Neo/SmartContract/Native/LedgerContract.cs

@@ -53,16 +53,19 @@ internal override ContractTask OnPersistAsync(ApplicationEngine engine)
             {
                 // It's possible that there are previously saved malicious conflict records for this transaction.
                 // If so, then remove it and store the relevant transaction itself.
-                engine.SnapshotCache.GetAndChange(CreateStorageKey(Prefix_Transaction, tx.Transaction.Hash), () => new StorageItem(new TransactionState())).FromReplica(new StorageItem(tx));
+                engine.SnapshotCache.GetAndChange(CreateStorageKey(Prefix_Transaction, tx.Transaction.Hash), () => new StorageItem(new TransactionState()))
+                    .FromReplica(new StorageItem(tx));
 
                 // Store transaction's conflicits.
                 var conflictingSigners = tx.Transaction.Signers.Select(s => s.Account);
                 foreach (var attr in tx.Transaction.GetAttributes<Conflicts>())
                 {
-                    engine.SnapshotCache.GetAndChange(CreateStorageKey(Prefix_Transaction, attr.Hash), () => new StorageItem(new TransactionState())).FromReplica(new StorageItem(new TransactionState() { BlockIndex = engine.PersistingBlock.Index }));
+                    engine.SnapshotCache.GetAndChange(CreateStorageKey(Prefix_Transaction, attr.Hash), () => new StorageItem(new TransactionState()))
+                        .FromReplica(new StorageItem(new TransactionState() { BlockIndex = engine.PersistingBlock.Index }));
                     foreach (var signer in conflictingSigners)
                     {
-                        engine.SnapshotCache.GetAndChange(CreateStorageKey(Prefix_Transaction, attr.Hash, signer), () => new StorageItem(new TransactionState())).FromReplica(new StorageItem(new TransactionState() { BlockIndex = engine.PersistingBlock.Index }));
+                        engine.SnapshotCache.GetAndChange(CreateStorageKey(Prefix_Transaction, attr.Hash, signer), () => new StorageItem(new TransactionState()))
+                            .FromReplica(new StorageItem(new TransactionState() { BlockIndex = engine.PersistingBlock.Index }));
                     }
                 }
             }
@@ -73,7 +76,9 @@ internal override ContractTask OnPersistAsync(ApplicationEngine engine)
 
         internal override ContractTask PostPersistAsync(ApplicationEngine engine)
         {
-            HashIndexState state = engine.SnapshotCache.GetAndChange(_currentBlock, () => new StorageItem(new HashIndexState())).GetInteroperable<HashIndexState>();
+            var state = engine.SnapshotCache.GetAndChange(_currentBlock, () => new StorageItem(new HashIndexState()))
+                // Don't need to seal because the size is fixed and it can't grow
+                .GetInteroperable<HashIndexState>();
             state.Hash = engine.PersistingBlock.Hash;
             state.Index = engine.PersistingBlock.Index;
             return ContractTask.CompletedTask;

src/Neo/SmartContract/Native/TransactionState.cs

@@ -9,6 +9,8 @@
 // Redistribution and use in source and binary forms with or without
 // modifications are permitted.
 
+#nullable enable
+
 using Neo.Extensions;
 using Neo.Network.P2P.Payloads;
 using Neo.VM;
@@ -25,17 +27,17 @@ public class TransactionState : IInteroperable
         /// <summary>
         /// The block containing this transaction.
         /// </summary>
-        public uint BlockIndex;
+        public uint BlockIndex { get; set; }
 
         /// <summary>
         /// The transaction, if the transaction is trimmed this value will be null
         /// </summary>
-        public Transaction Transaction;
+        public Transaction? Transaction { get; set; }
 
         /// <summary>
         /// The execution state
         /// </summary>
-        public VMState State;
+        public VMState State { get; set; }
 
         private ReadOnlyMemory<byte> _rawTransaction;
 
@@ -52,7 +54,7 @@ IInteroperable IInteroperable.Clone()
 
         void IInteroperable.FromReplica(IInteroperable replica)
         {
-            TransactionState from = (TransactionState)replica;
+            var from = (TransactionState)replica;
             BlockIndex = from.BlockIndex;
             Transaction = from.Transaction;
             State = from.State;
@@ -62,7 +64,7 @@ void IInteroperable.FromReplica(IInteroperable replica)
 
         void IInteroperable.FromStackItem(StackItem stackItem)
         {
-            Struct @struct = (Struct)stackItem;
+            var @struct = (Struct)stackItem;
             BlockIndex = (uint)@struct[0].GetInteger();
 
             // Conflict record.
@@ -84,3 +86,5 @@ StackItem IInteroperable.ToStackItem(IReferenceCounter referenceCounter)
         }
     }
 }
+
+#nullable disable