Refactor Simulate in Blockchain Bridge to be generic, enabling suppor…

…t for SimulateBlockTracer, GethLikeBlockMemoryTracer, and ParityLikeBlockTracer while ensuring flexibility in SimulateBlockResult<T> and updating test cases accordingly.

src/Nethermind/Nethermind.Facade/BlockchainBridge.cs

@@ -15,6 +15,8 @@
 using Nethermind.Int256;
 using Nethermind.Evm;
 using Nethermind.Evm.Tracing;
+using Nethermind.Evm.Tracing.GethStyle;
+using Nethermind.Evm.Tracing.ParityStyle;
 using Nethermind.Trie;
 using Nethermind.TxPool;
 using Block = Nethermind.Core.Block;
@@ -29,6 +31,7 @@
 using Nethermind.Facade.Find;
 using Nethermind.Facade.Proxy.Models.Simulate;
 using Nethermind.Facade.Simulate;
+using Nethermind.Facade.Tracing;
 using Transaction = Nethermind.Core.Transaction;
 
 namespace Nethermind.Facade
@@ -165,15 +168,32 @@ public CallOutput Call(BlockHeader header, Transaction tx, Dictionary<Address, A
             };
         }
 
-        public SimulateOutput Simulate(BlockHeader header, SimulatePayload<TransactionWithSourceDetails> payload, CancellationToken cancellationToken)
+        public SimulateOutput<T> Simulate<T>(
+            BlockHeader header,
+            SimulatePayload<TransactionWithSourceDetails> payload,
+            CancellationToken cancellationToken,
+            ITracerFactory<T> tracerFactory)
+            where T : class
         {
-            SimulateBlockTracer simulateOutputTracer = new(payload.TraceTransfers, payload.ReturnFullTransactionObjects, _specProvider);
-            BlockReceiptsTracer tracer = new();
-            tracer.SetOtherTracer(simulateOutputTracer);
-            SimulateOutput result = new();
+            var tracer = tracerFactory.CreateTracer(payload.TraceTransfers, payload.ReturnFullTransactionObjects, _specProvider);
+            BlockReceiptsTracer receiptsTracer = new();
+            receiptsTracer.SetOtherTracer(tracer);
+
+            SimulateOutput<T> result = new();
+
             try
             {
-                if (!_simulateBridgeHelper.TrySimulate(header, payload, simulateOutputTracer, new CancellationBlockTracer(tracer, cancellationToken), out string error))
+                if (tracer is not SimulateBlockTracer validatedTracer)
+                {
+                    throw new InvalidOperationException($"Unsupported tracer type: {typeof(T).Name}");
+                }
+
+                if (!_simulateBridgeHelper.TrySimulate(
+                        header,
+                        payload,
+                        validatedTracer,
+                        new CancellationBlockTracer(receiptsTracer, cancellationToken),
+                        out string error))
                 {
                     result.Error = error;
                 }
@@ -187,10 +207,19 @@ public SimulateOutput Simulate(BlockHeader header, SimulatePayload<TransactionWi
                 result.Error = ex.ToString();
             }
 
-            result.Items = simulateOutputTracer.Results;
+            if (tracer is SimulateBlockTracer simulateTracer)
+            {
+                result.Items = simulateTracer.Results as IReadOnlyList<SimulateBlockResult<T>>;
+            }
+            else
+            {
+                throw new InvalidOperationException($"Tracer type {typeof(T).Name} does not support 'Results'");
+            }
+
             return result;
         }
 
+
         public CallOutput EstimateGas(BlockHeader header, Transaction tx, int errorMargin, Dictionary<Address, AccountOverride>? stateOverride, CancellationToken cancellationToken)
         {
             using IOverridableTxProcessingScope scope = _processingEnv.BuildAndOverride(header, stateOverride);
@@ -432,5 +461,44 @@ public IEnumerable<FilterLog> FindLogs(LogFilter filter, CancellationToken cance
         {
             return _logFinder.FindLogs(filter, cancellationToken);
         }
+
+        public class SimulateBlockTracerFactory : ITracerFactory<SimulateCallResult>
+        {
+            public IBlockTracer<SimulateCallResult> CreateTracer(bool traceTransfers, bool returnFullTransactionObjects, ISpecProvider specProvider)
+            {
+                return (IBlockTracer<SimulateCallResult>)new SimulateBlockTracer(traceTransfers, returnFullTransactionObjects, specProvider);
+            }
+        }
+
+        public class GethLikeBlockMemoryTracerFactory : ITracerFactory<GethLikeTxTrace>
+        {
+            private readonly GethTraceOptions _options;
+
+            public GethLikeBlockMemoryTracerFactory(GethTraceOptions options)
+            {
+                _options = options;
+            }
+
+            public IBlockTracer<GethLikeTxTrace> CreateTracer(bool traceTransfers, bool returnFullTransactionObjects, ISpecProvider specProvider)
+            {
+                return new GethLikeBlockMemoryTracer(_options);
+            }
+        }
+
+        public class ParityLikeBlockTracerFactory : ITracerFactory<ParityLikeTxTrace>
+        {
+            private readonly ParityTraceTypes _types;
+
+            public ParityLikeBlockTracerFactory(ParityTraceTypes types)
+            {
+                _types = types;
+            }
+
+            public IBlockTracer<ParityLikeTxTrace> CreateTracer(bool traceTransfers, bool returnFullTransactionObjects, ISpecProvider specProvider)
+            {
+                return new ParityLikeBlockTracer(_types);
+            }
+        }
+
     }
 }

src/Nethermind/Nethermind.Facade/IBlockchainBridge.cs

@@ -8,6 +8,8 @@
 using Nethermind.Core;
 using Nethermind.Core.Crypto;
 using Nethermind.Evm;
+using Nethermind.Facade;
+using Nethermind.Facade.Tracing;
 using Nethermind.Facade.Filters;
 using Nethermind.Facade.Find;
 using Nethermind.Facade.Simulate;
@@ -28,7 +30,7 @@ public interface IBlockchainBridge : ILogFinder
         (TxReceipt? Receipt, TxGasInfo? GasInfo, int LogIndexStart) GetReceiptAndGasInfo(Hash256 txHash);
         (TxReceipt? Receipt, Transaction? Transaction, UInt256? baseFee) GetTransaction(Hash256 txHash, bool checkTxnPool = true);
         CallOutput Call(BlockHeader header, Transaction tx, Dictionary<Address, AccountOverride>? stateOverride = null, CancellationToken cancellationToken = default);
-        SimulateOutput Simulate(BlockHeader header, SimulatePayload<TransactionWithSourceDetails> payload, CancellationToken cancellationToken);
+        SimulateOutput<T> Simulate<T>(BlockHeader header, SimulatePayload<TransactionWithSourceDetails> payload, CancellationToken cancellationToken, ITracerFactory<T> tracerFactory) where T : class;
         CallOutput EstimateGas(BlockHeader header, Transaction tx, int errorMarginBasisPoints, Dictionary<Address, AccountOverride>? stateOverride = null, CancellationToken cancellationToken = default);
 
         CallOutput CreateAccessList(BlockHeader header, Transaction tx, CancellationToken cancellationToken, bool optimize);

src/Nethermind/Nethermind.Facade/Proxy/Models/Simulate/SimulateBlockResult.cs

@@ -8,8 +8,8 @@
 
 namespace Nethermind.Facade.Proxy.Models.Simulate;
 
-public class SimulateBlockResult(Block source, bool includeFullTransactionData, ISpecProvider specProvider)
+public class SimulateBlockResult<T>(Block source, bool includeFullTransactionData, ISpecProvider specProvider)
     : BlockForRpc(source, includeFullTransactionData, specProvider)
 {
-    public List<SimulateCallResult> Calls { get; set; } = new();
+    public List<T> Calls { get; set; } = new();
 }

src/Nethermind/Nethermind.Facade/Simulate/SimulateBlockTracer.cs

@@ -15,7 +15,7 @@ public class SimulateBlockTracer(bool isTracingLogs, bool includeFullTxData, ISp
     private readonly List<SimulateTxMutatorTracer> _txTracers = new();
 
     private Block _currentBlock = null!;
-    public List<SimulateBlockResult> Results { get; } = new();
+    public List<SimulateBlockResult<SimulateCallResult>> Results { get; } = new();
 
     public override void StartNewBlockTrace(Block block)
     {
@@ -40,7 +40,7 @@ public override ITxTracer StartNewTxTrace(Transaction? tx)
 
     public override void EndBlockTrace()
     {
-        SimulateBlockResult? result = new(_currentBlock, includeFullTxData, spec)
+        SimulateBlockResult<SimulateCallResult>? result = new(_currentBlock, includeFullTxData, spec)
         {
             Calls = _txTracers.Select(t => t.TraceResult).ToList(),
         };

src/Nethermind/Nethermind.Facade/Simulate/SimulateBridgeHelper.cs

@@ -121,7 +121,7 @@ private bool TrySimulate(
 
     private static void CheckMisssingAndSetTracedDefaults(SimulateBlockTracer simulateOutputTracer, Block processedBlock)
     {
-        SimulateBlockResult current = simulateOutputTracer.Results.Last();
+        SimulateBlockResult<SimulateCallResult> current = simulateOutputTracer.Results.Last();
         current.StateRoot = processedBlock.StateRoot ?? Hash256.Zero;
         current.ParentBeaconBlockRoot = processedBlock.ParentBeaconBlockRoot ?? Hash256.Zero;
         current.TransactionsRoot = processedBlock.Header.TxRoot;

src/Nethermind/Nethermind.Facade/Simulate/SimulateOutput.cs

@@ -6,10 +6,10 @@
 
 namespace Nethermind.Facade.Simulate;
 
-public class SimulateOutput
+public class SimulateOutput<T>
 {
     public string? Error { get; set; }
     public int? ErrorCode { get; set; }
 
-    public IReadOnlyList<SimulateBlockResult> Items { get; set; }
+    public IReadOnlyList<SimulateBlockResult<T>> Items { get; set; }
 }

src/Nethermind/Nethermind.Facade/Tracing/ITracerFactory.cs

@@ -0,0 +1,10 @@
+using Nethermind.Core.Specs;
+using Nethermind.Evm.Tracing;
+
+namespace Nethermind.Facade.Tracing
+{
+    public interface ITracerFactory<T>
+    {
+        IBlockTracer<T> CreateTracer(bool traceTransfers, bool returnFullTransactionObjects, ISpecProvider specProvider);
+    }
+}

src/Nethermind/Nethermind.JsonRpc.Test/JsonRpcServiceTests.cs

@@ -99,9 +99,9 @@ public void CanRunEthSimulateV1Empty()
         string serializedCall = new EthereumJsonSerializer().Serialize(payload);
         IEthRpcModule ethRpcModule = Substitute.For<IEthRpcModule>();
         ethRpcModule.eth_simulateV1(payload).ReturnsForAnyArgs(static _ =>
-            ResultWrapper<IReadOnlyList<SimulateBlockResult>>.Success(Array.Empty<SimulateBlockResult>()));
+            ResultWrapper<IReadOnlyList<SimulateBlockResult<SimulateCallResult>>>.Success(Array.Empty<SimulateBlockResult<SimulateCallResult>>()));
         JsonRpcSuccessResponse? response = TestRequest(ethRpcModule, "eth_simulateV1", serializedCall) as JsonRpcSuccessResponse;
-        Assert.That(response?.Result, Is.EqualTo(Array.Empty<SimulateBlockResult>()));
+        Assert.That(response?.Result, Is.EqualTo(Array.Empty<SimulateBlockResult<SimulateCallResult>>()));
     }
 
 

src/Nethermind/Nethermind.JsonRpc.Test/Modules/Eth/EthSimulateTestsPrecompilesWithRedirection.cs

@@ -63,7 +63,7 @@ public async Task Test_eth_simulate_create()
         //will mock our GetCachedCodeInfo function - it shall be called 3 times if redirect is working, 2 times if not
         SimulateTxExecutor executor = new(chain.Bridge, chain.BlockFinder, new JsonRpcConfig(), new BlocksConfig().SecondsPerSlot);
 
-        ResultWrapper<IReadOnlyList<SimulateBlockResult>> result = executor.Execute(payload, BlockParameter.Latest);
+        ResultWrapper<IReadOnlyList<SimulateBlockResult<SimulateCallResult>>> result = executor.Execute(payload, BlockParameter.Latest);
 
         //Check results
         byte[]? returnData = result.Data[0].Calls.First().ReturnData;
@@ -181,7 +181,7 @@ function ecrecover(bytes32 hash, uint8 v, bytes32 r, bytes32 s) public  returns(
         Debug.Assert(contractAddress is not null, nameof(contractAddress) + " is not null");
         Assert.That(chain.State.AccountExists(contractAddress), Is.True);
 
-        ResultWrapper<IReadOnlyList<SimulateBlockResult>> result = executor.Execute(payload, BlockParameter.Latest);
+        ResultWrapper<IReadOnlyList<SimulateBlockResult<SimulateCallResult>>> result = executor.Execute(payload, BlockParameter.Latest);
 
         //Check results
         byte[] addressBytes = result.Data[0].Calls[0].ReturnData!.SliceWithZeroPaddingEmptyOnError(12, 20);

src/Nethermind/Nethermind.JsonRpc.Test/Modules/Eth/Simulate/EthSimulateTestsBlocksAndTransactions.cs

@@ -76,11 +76,11 @@ public async Task Test_eth_simulate_serialisation()
 
         //will mock our GetCachedCodeInfo function - it shall be called 3 times if redirect is working, 2 times if not
         SimulateTxExecutor executor = new(chain.Bridge, chain.BlockFinder, new JsonRpcConfig(), new BlocksConfig().SecondsPerSlot);
-        ResultWrapper<IReadOnlyList<SimulateBlockResult>> result = executor.Execute(payload, BlockParameter.Latest);
-        IReadOnlyList<SimulateBlockResult> data = result.Data;
+        ResultWrapper<IReadOnlyList<SimulateBlockResult<SimulateCallResult>>> result = executor.Execute(payload, BlockParameter.Latest);
+        IReadOnlyList<SimulateBlockResult<SimulateCallResult>> data = result.Data;
         Assert.That(data.Count, Is.EqualTo(7));
 
-        SimulateBlockResult blockResult = data.Last();
+        SimulateBlockResult<SimulateCallResult> blockResult = data.Last();
         blockResult.Calls.Select(static c => c.Status).Should().BeEquivalentTo(new[] { (ulong)ResultType.Success, (ulong)ResultType.Success });
 
     }
@@ -150,13 +150,13 @@ public async Task Test_eth_simulate_eth_moved()
 
         //will mock our GetCachedCodeInfo function - it shall be called 3 times if redirect is working, 2 times if not
         SimulateTxExecutor executor = new(chain.Bridge, chain.BlockFinder, new JsonRpcConfig(), new BlocksConfig().SecondsPerSlot);
-        ResultWrapper<IReadOnlyList<SimulateBlockResult>> result =
+        ResultWrapper<IReadOnlyList<SimulateBlockResult<SimulateCallResult>>> result =
             executor.Execute(payload, BlockParameter.Latest);
-        IReadOnlyList<SimulateBlockResult> data = result.Data;
+        IReadOnlyList<SimulateBlockResult<SimulateCallResult>> data = result.Data;
 
         Assert.That(data.Count, Is.EqualTo(9));
 
-        SimulateBlockResult blockResult = data[0];
+        SimulateBlockResult<SimulateCallResult> blockResult = data[0];
         Assert.That(blockResult.Calls.Count, Is.EqualTo(2));
         blockResult = data.Last();
         Assert.That(blockResult.Calls.Count, Is.EqualTo(2));
@@ -235,7 +235,7 @@ public async Task Test_eth_simulate_transactions_forced_fail()
         //will mock our GetCachedCodeInfo function - it shall be called 3 times if redirect is working, 2 times if not
         SimulateTxExecutor executor = new(chain.Bridge, chain.BlockFinder, new JsonRpcConfig(), new BlocksConfig().SecondsPerSlot);
 
-        ResultWrapper<IReadOnlyList<SimulateBlockResult>> result =
+        ResultWrapper<IReadOnlyList<SimulateBlockResult<SimulateCallResult>>> result =
             executor.Execute(payload, BlockParameter.Latest);
         Assert.That(result.Result!.Error!.Contains("higher than sender balance"), Is.True);
     }

src/Nethermind/Nethermind.JsonRpc.Test/Modules/Eth/Simulate/EthSimulateTestsHiveBase.cs

@@ -72,7 +72,7 @@ public async Task TestsimulateHive(string name, string data)
         SimulatePayload<TransactionForRpc>? payload = serializer.Deserialize<SimulatePayload<TransactionForRpc>>(data);
         TestRpcBlockchain chain = await EthRpcSimulateTestsBase.CreateChain();
         Console.WriteLine($"current test: {name}");
-        ResultWrapper<IReadOnlyList<SimulateBlockResult>> result =
+        ResultWrapper<IReadOnlyList<SimulateBlockResult<SimulateCallResult>>> result =
             chain.EthRpcModule.eth_simulateV1(payload!, BlockParameter.Latest);
 
         Console.WriteLine();

src/Nethermind/Nethermind.JsonRpc.Test/Modules/Eth/Simulate/EthSimulateTestsSimplePrecompiles.cs

@@ -94,7 +94,12 @@ public async Task Test_eth_simulate_erc()
             TraceTransfers = true
         };
 
-        SimulateOutput result = chain.Bridge.Simulate(chain.BlockFinder.Head?.Header!, payload, CancellationToken.None);
+        SimulateOutput<SimulateCallResult> result = chain.Bridge.Simulate(
+            chain.BlockFinder.Head?.Header!,
+            payload,
+            CancellationToken.None,
+            new BlockchainBridge.SimulateBlockTracerFactory()
+        );
 
         byte[] addressBytes = result.Items[0].Calls[0].ReturnData!.SliceWithZeroPaddingEmptyOnError(12, 20);
         Address resultingAddress = new(addressBytes);

src/Nethermind/Nethermind.JsonRpc/Modules/Eth/EthRpcModule.cs

@@ -342,9 +342,13 @@ public ResultWrapper<string> eth_call(TransactionForRpc transactionCall, BlockPa
         new CallTxExecutor(_blockchainBridge, _blockFinder, _rpcConfig)
             .ExecuteTx(transactionCall, blockParameter, stateOverride);
 
-    public ResultWrapper<IReadOnlyList<SimulateBlockResult>> eth_simulateV1(SimulatePayload<TransactionForRpc> payload, BlockParameter? blockParameter = null) =>
-        new SimulateTxExecutor(_blockchainBridge, _blockFinder, _rpcConfig, _secondsPerSlot)
+    public ResultWrapper<IReadOnlyList<SimulateBlockResult<SimulateCallResult>>> eth_simulateV1(
+        SimulatePayload<TransactionForRpc> payload, BlockParameter? blockParameter = null)
+    {
+        return new SimulateTxExecutor(_blockchainBridge, _blockFinder, _rpcConfig, _secondsPerSlot)
             .Execute(payload, blockParameter);
+    }
+
 
     public ResultWrapper<UInt256?> eth_estimateGas(TransactionForRpc transactionCall, BlockParameter? blockParameter, Dictionary<Address, AccountOverride>? stateOverride = null) =>
         new EstimateGasTxExecutor(_blockchainBridge, _blockFinder, _rpcConfig)