Add diagnostic for ApplicationEngine (#2613)

src/neo/IO/Caching/Tree.cs

@@ -0,0 +1,35 @@
+// Copyright (C) 2015-2021 The Neo Project.
+// 
+// The neo is free software distributed under the MIT software license, 
+// see the accompanying file LICENSE in the main directory of the
+// project or http://www.opensource.org/licenses/mit-license.php 
+// for more details.
+// 
+// Redistribution and use in source and binary forms with or without
+// modifications are permitted.
+
+using System;
+using System.Collections.Generic;
+
+namespace Neo.IO.Caching
+{
+    public class Tree<T>
+    {
+        public TreeNode<T> Root { get; private set; }
+
+        public TreeNode<T> AddRoot(T item)
+        {
+            if (Root is not null)
+                throw new InvalidOperationException();
+            Root = new TreeNode<T>(item, null);
+            return Root;
+        }
+
+        public IEnumerable<T> GetItems()
+        {
+            if (Root is null) yield break;
+            foreach (T item in Root.GetItems())
+                yield return item;
+        }
+    }
+}

src/neo/IO/Caching/TreeNode.cs

@@ -0,0 +1,43 @@
+// Copyright (C) 2015-2021 The Neo Project.
+// 
+// The neo is free software distributed under the MIT software license, 
+// see the accompanying file LICENSE in the main directory of the
+// project or http://www.opensource.org/licenses/mit-license.php 
+// for more details.
+// 
+// Redistribution and use in source and binary forms with or without
+// modifications are permitted.
+
+using System.Collections.Generic;
+
+namespace Neo.IO.Caching
+{
+    public class TreeNode<T>
+    {
+        public T Item { get; }
+        public TreeNode<T> Parent { get; }
+
+        private readonly List<TreeNode<T>> children = new();
+
+        internal TreeNode(T item, TreeNode<T> parent)
+        {
+            Item = item;
+            Parent = parent;
+        }
+
+        public TreeNode<T> AddChild(T item)
+        {
+            TreeNode<T> child = new(item, this);
+            children.Add(child);
+            return child;
+        }
+
+        internal IEnumerable<T> GetItems()
+        {
+            yield return Item;
+            foreach (var child in children)
+                foreach (T item in child.GetItems())
+                    yield return item;
+        }
+    }
+}

src/neo/Plugins/IApplicationEngineProvider.cs

@@ -28,7 +28,8 @@ public interface IApplicationEngineProvider
         /// <param name="persistingBlock">The block being persisted. It should be <see langword="null"/> if the <paramref name="trigger"/> is <see cref="TriggerType.Verification"/>.</param>
         /// <param name="settings">The <see cref="ProtocolSettings"/> used by the engine.</param>
         /// <param name="gas">The maximum gas used in this execution. The execution will fail when the gas is exhausted.</param>
+        /// <param name="diagnostic">The diagnostic to be used by the <see cref="ApplicationEngine"/>.</param>
         /// <returns>The engine instance created.</returns>
-        ApplicationEngine Create(TriggerType trigger, IVerifiable container, DataCache snapshot, Block persistingBlock, ProtocolSettings settings, long gas);
+        ApplicationEngine Create(TriggerType trigger, IVerifiable container, DataCache snapshot, Block persistingBlock, ProtocolSettings settings, long gas, Diagnostic diagnostic);
     }
 }

src/neo/SmartContract/ApplicationEngine.cs

@@ -9,6 +9,7 @@
 // modifications are permitted.
 
 using Neo.IO;
+using Neo.IO.Caching;
 using Neo.IO.Json;
 using Neo.Network.P2P.Payloads;
 using Neo.Persistence;
@@ -50,6 +51,7 @@ public partial class ApplicationEngine : ExecutionEngine
 
         private static IApplicationEngineProvider applicationEngineProvider;
         private static Dictionary<uint, InteropDescriptor> services;
+        private TreeNode<UInt160> currentNodeOfInvocationTree = null;
         private readonly long gas_amount;
         private List<NotifyEventArgs> notifications;
         private List<IDisposable> disposables;
@@ -64,6 +66,11 @@ public partial class ApplicationEngine : ExecutionEngine
         /// </summary>
         public static IReadOnlyDictionary<uint, InteropDescriptor> Services => services;
 
+        /// <summary>
+        /// The diagnostic used by the engine. This property can be <see langword="null"/>.
+        /// </summary>
+        public Diagnostic Diagnostic { get; }
+
         private List<IDisposable> Disposables => disposables ??= new List<IDisposable>();
 
         /// <summary>
@@ -135,14 +142,16 @@ public partial class ApplicationEngine : ExecutionEngine
         /// <param name="persistingBlock">The block being persisted. It should be <see langword="null"/> if the <paramref name="trigger"/> is <see cref="TriggerType.Verification"/>.</param>
         /// <param name="settings">The <see cref="Neo.ProtocolSettings"/> used by the engine.</param>
         /// <param name="gas">The maximum gas used in this execution. The execution will fail when the gas is exhausted.</param>
-        protected unsafe ApplicationEngine(TriggerType trigger, IVerifiable container, DataCache snapshot, Block persistingBlock, ProtocolSettings settings, long gas)
+        /// <param name="diagnostic">The diagnostic to be used by the <see cref="ApplicationEngine"/>.</param>
+        protected unsafe ApplicationEngine(TriggerType trigger, IVerifiable container, DataCache snapshot, Block persistingBlock, ProtocolSettings settings, long gas, Diagnostic diagnostic)
         {
             this.Trigger = trigger;
             this.ScriptContainer = container;
             this.Snapshot = snapshot;
             this.PersistingBlock = persistingBlock;
             this.ProtocolSettings = settings;
             this.gas_amount = gas;
+            this.Diagnostic = diagnostic;
             this.exec_fee_factor = snapshot is null || persistingBlock?.Index == 0 ? PolicyContract.DefaultExecFeeFactor : NativeContract.Policy.GetExecFeeFactor(Snapshot);
             this.StoragePrice = snapshot is null || persistingBlock?.Index == 0 ? PolicyContract.DefaultStoragePrice : NativeContract.Policy.GetStoragePrice(Snapshot);
             this.nonceData = container is Transaction tx ? tx.Hash.ToArray()[..16] : new byte[16];
@@ -250,6 +259,8 @@ internal ContractTask<T> CallFromNativeContract<T>(UInt160 callingScriptHash, UI
         protected override void ContextUnloaded(ExecutionContext context)
         {
             base.ContextUnloaded(context);
+            if (Diagnostic is not null)
+                currentNodeOfInvocationTree = currentNodeOfInvocationTree.Parent;
             if (!contractTasks.Remove(context, out var awaiter)) return;
             if (UncaughtException is not null)
                 throw new VMUnhandledException(UncaughtException);
@@ -265,21 +276,29 @@ protected override void ContextUnloaded(ExecutionContext context)
         /// <param name="persistingBlock">The block being persisted. It should be <see langword="null"/> if the <paramref name="trigger"/> is <see cref="TriggerType.Verification"/>.</param>
         /// <param name="settings">The <see cref="Neo.ProtocolSettings"/> used by the engine.</param>
         /// <param name="gas">The maximum gas used in this execution. The execution will fail when the gas is exhausted.</param>
+        /// <param name="diagnostic">The diagnostic to be used by the <see cref="ApplicationEngine"/>.</param>
         /// <returns>The engine instance created.</returns>
-        public static ApplicationEngine Create(TriggerType trigger, IVerifiable container, DataCache snapshot, Block persistingBlock = null, ProtocolSettings settings = null, long gas = TestModeGas)
+        public static ApplicationEngine Create(TriggerType trigger, IVerifiable container, DataCache snapshot, Block persistingBlock = null, ProtocolSettings settings = null, long gas = TestModeGas, Diagnostic diagnostic = null)
         {
-            return applicationEngineProvider?.Create(trigger, container, snapshot, persistingBlock, settings, gas)
-                  ?? new ApplicationEngine(trigger, container, snapshot, persistingBlock, settings, gas);
+            return applicationEngineProvider?.Create(trigger, container, snapshot, persistingBlock, settings, gas, diagnostic)
+                  ?? new ApplicationEngine(trigger, container, snapshot, persistingBlock, settings, gas, diagnostic);
         }
 
         protected override void LoadContext(ExecutionContext context)
         {
             // Set default execution context state
-
             var state = context.GetState<ExecutionContextState>();
             state.ScriptHash ??= ((byte[])context.Script).ToScriptHash();
             invocationCounter.TryAdd(state.ScriptHash, 1);
 
+            if (Diagnostic is not null)
+            {
+                if (currentNodeOfInvocationTree is null)
+                    currentNodeOfInvocationTree = Diagnostic.InvocationTree.AddRoot(state.ScriptHash);
+                else
+                    currentNodeOfInvocationTree = currentNodeOfInvocationTree.AddChild(state.ScriptHash);
+            }
+
             base.LoadContext(context);
         }
 
@@ -531,11 +550,12 @@ internal static void ResetApplicationEngineProvider()
         /// <param name="settings">The <see cref="Neo.ProtocolSettings"/> used by the engine.</param>
         /// <param name="offset">The initial position of the instruction pointer.</param>
         /// <param name="gas">The maximum gas used in this execution. The execution will fail when the gas is exhausted.</param>
+        /// <param name="diagnostic">The diagnostic to be used by the <see cref="ApplicationEngine"/>.</param>
         /// <returns>The engine instance created.</returns>
-        public static ApplicationEngine Run(byte[] script, DataCache snapshot, IVerifiable container = null, Block persistingBlock = null, ProtocolSettings settings = null, int offset = 0, long gas = TestModeGas)
+        public static ApplicationEngine Run(byte[] script, DataCache snapshot, IVerifiable container = null, Block persistingBlock = null, ProtocolSettings settings = null, int offset = 0, long gas = TestModeGas, Diagnostic diagnostic = null)
         {
             persistingBlock ??= CreateDummyBlock(snapshot, settings ?? ProtocolSettings.Default);
-            ApplicationEngine engine = Create(TriggerType.Application, container, snapshot, persistingBlock, settings, gas);
+            ApplicationEngine engine = Create(TriggerType.Application, container, snapshot, persistingBlock, settings, gas, diagnostic);
             engine.LoadScript(script, initialPosition: offset);
             engine.Execute();
             return engine;

src/neo/SmartContract/Diagnostic.cs

@@ -0,0 +1,19 @@
+// Copyright (C) 2015-2021 The Neo Project.
+// 
+// The neo is free software distributed under the MIT software license, 
+// see the accompanying file LICENSE in the main directory of the
+// project or http://www.opensource.org/licenses/mit-license.php 
+// for more details.
+// 
+// Redistribution and use in source and binary forms with or without
+// modifications are permitted.
+
+using Neo.IO.Caching;
+
+namespace Neo.SmartContract
+{
+    public class Diagnostic
+    {
+        public Tree<UInt160> InvocationTree { get; } = new();
+    }
+}

tests/neo.UnitTests/SmartContract/UT_ApplicationEngine.cs

@@ -50,10 +50,11 @@ public void TestCreateDummyBlock()
         {
             var snapshot = TestBlockchain.GetTestSnapshot();
             byte[] SyscallSystemRuntimeCheckWitnessHash = new byte[] { 0x68, 0xf8, 0x27, 0xec, 0x8c };
-            ApplicationEngine engine = ApplicationEngine.Run(SyscallSystemRuntimeCheckWitnessHash, snapshot);
+            ApplicationEngine engine = ApplicationEngine.Run(SyscallSystemRuntimeCheckWitnessHash, snapshot, diagnostic: new Diagnostic());
             engine.PersistingBlock.Version.Should().Be(0);
             engine.PersistingBlock.PrevHash.Should().Be(TestBlockchain.TheNeoSystem.GenesisBlock.Hash);
             engine.PersistingBlock.MerkleRoot.Should().Be(new UInt256());
+            string.Join(",", engine.Diagnostic.InvocationTree.GetItems()).Should().Be("0x67bd6dffcf36468c9ffbe6cc4cd0cb7108304d24");
         }
     }
 }

tests/neo.UnitTests/SmartContract/UT_ApplicationEngineProvider.cs

@@ -63,16 +63,16 @@ public void TestCanResetAppEngineProviderTwice()
 
         class TestProvider : IApplicationEngineProvider
         {
-            public ApplicationEngine Create(TriggerType trigger, IVerifiable container, DataCache snapshot, Block persistingBlock, ProtocolSettings settings, long gas)
+            public ApplicationEngine Create(TriggerType trigger, IVerifiable container, DataCache snapshot, Block persistingBlock, ProtocolSettings settings, long gas, Diagnostic diagnostic)
             {
-                return new TestEngine(trigger, container, snapshot, persistingBlock, settings, gas);
+                return new TestEngine(trigger, container, snapshot, persistingBlock, settings, gas, diagnostic);
             }
         }
 
         class TestEngine : ApplicationEngine
         {
-            public TestEngine(TriggerType trigger, IVerifiable container, DataCache snapshot, Block persistingBlock, ProtocolSettings settings, long gas)
-                : base(trigger, container, snapshot, persistingBlock, settings, gas)
+            public TestEngine(TriggerType trigger, IVerifiable container, DataCache snapshot, Block persistingBlock, ProtocolSettings settings, long gas, Diagnostic diagnostic)
+                : base(trigger, container, snapshot, persistingBlock, settings, gas, diagnostic)
             {
             }
         }