Incorrect Gas Estimation

src/Nethermind/Nethermind.Blockchain.Test/TransactionProcessorTests.cs

@@ -331,7 +331,16 @@ public long Should_not_estimate_tx_with_high_value(UInt256 txValue)
         GasEstimator estimator = new(_transactionProcessor, _stateProvider, _specProvider, blocksConfig);
 
         long estimate = estimator.Estimate(tx, block.Header, tracer, out string? err, 0);
-        Assert.That(err, Is.Null);
+
+        if (txValue > AccountBalance)
+        {
+            Assert.That(err, Is.Not.Null); // Should have error
+            Assert.That(err, Is.EqualTo("Transaction execution fails"));
+        }
+        else
+        {
+            Assert.That(err, Is.Null); // Should succeed
+        }
 
         return estimate;
     }

src/Nethermind/Nethermind.Blockchain/Tracing/EstimateGasTracer.cs

@@ -38,6 +38,8 @@ public EstimateGasTracer()
 
     public byte StatusCode { get; set; }
 
+    public bool OutOfGas { get; private set; }
+
     public override void MarkAsSuccess(Address recipient, GasConsumed gasSpent, byte[] output, LogEntry[] logs,
         Hash256? stateRoot = null)
     {
@@ -105,6 +107,7 @@ public override void ReportAction(long gas, UInt256 value, Address from, Address
     {
         if (_currentNestingLevel == -1)
         {
+            OutOfGas = false;
             IntrinsicGasAt = gas;
         }
 
@@ -131,14 +134,21 @@ public override void ReportActionEnd(long gas, Address deploymentAddress, ReadOn
 
     public override void ReportActionError(EvmExceptionType exceptionType)
     {
+        ReportOperationError(exceptionType);
         UpdateAdditionalGas();
     }
 
     public void ReportActionError(EvmExceptionType exceptionType, long gasLeft)
     {
+        ReportOperationError(exceptionType);
         UpdateAdditionalGas(gasLeft);
     }
 
+    public override void ReportOperationError(EvmExceptionType error)
+    {
+        OutOfGas |= error == EvmExceptionType.OutOfGas || error == EvmExceptionType.Revert;
+    }
+
     private void UpdateAdditionalGas(long? gasLeft = null)
     {
         if (_isInPrecompile)

src/Nethermind/Nethermind.Blockchain/Tracing/GasEstimator.cs

@@ -4,7 +4,6 @@
 using System.Threading;
 using Nethermind.Config;
 using Nethermind.Core;
-using Nethermind.Core.Crypto;
 using Nethermind.Core.Specs;
 using Nethermind.Evm;
 using Nethermind.Evm.TransactionProcessing;
@@ -62,7 +61,24 @@ public long Estimate(Transaction tx, BlockHeader header, EstimateGasTracer gasTr
         UInt256 senderBalance = _stateProvider.GetBalance(tx.SenderAddress);
         if (tx.ValueRef != UInt256.Zero && tx.ValueRef > senderBalance && !tx.IsSystem())
         {
-            return gasTracer.CalculateAdditionalGasRequired(tx, releaseSpec);
+            long additionalGas = gasTracer.CalculateAdditionalGasRequired(tx, releaseSpec);
+            if (additionalGas == 0)
+            {
+                // If no additional gas can help, it's an insufficient balance error
+                if (gasTracer.OutOfGas)
+                {
+                    err = "Gas estimation failed due to out of gas";
+                }
+                else if (gasTracer.StatusCode == StatusCode.Failure)
+                {
+                    err = gasTracer.Error ?? "Transaction execution fails";
+                }
+                else
+                {
+                    err = "insufficient balance";
+                }
+            }
+            return additionalGas;
         }
 
         var lowerBound = IntrinsicGasCalculator.Calculate(tx, releaseSpec).MinimalGas;
@@ -82,19 +98,21 @@ public long Estimate(Transaction tx, BlockHeader header, EstimateGasTracer gasTr
         }
 
         // Execute binary search to find the optimal gas estimation.
-        return BinarySearchEstimate(leftBound, rightBound, tx, header, gasTracer, errorMargin, token);
+        return BinarySearchEstimate(leftBound, rightBound, tx, header, gasTracer, errorMargin, token, out err);
     }
 
     private long BinarySearchEstimate(long leftBound, long rightBound, Transaction tx, BlockHeader header,
-        EstimateGasTracer gasTracer, int errorMargin, CancellationToken token)
+        EstimateGasTracer gasTracer, int errorMargin, CancellationToken token, out string? err)
     {
+        err = null;
         double marginWithDecimals = errorMargin == 0 ? 1 : errorMargin / 10000d + 1;
+
         //This approach is similar to Geth, by starting from an optimistic guess the number of iterations is greatly reduced in most cases
         long optimisticGasEstimate =
             (long)((gasTracer.GasSpent + gasTracer.TotalRefund + GasCostOf.CallStipend) * marginWithDecimals);
         if (optimisticGasEstimate > leftBound && optimisticGasEstimate < rightBound)
         {
-            if (TryExecutableTransaction(tx, header, optimisticGasEstimate, token))
+            if (TryExecutableTransaction(tx, header, optimisticGasEstimate, token, gasTracer))
                 rightBound = optimisticGasEstimate;
             else
                 leftBound = optimisticGasEstimate;
@@ -106,7 +124,7 @@ private long BinarySearchEstimate(long leftBound, long rightBound, Transaction t
                && leftBound + 1 < rightBound)
         {
             long mid = (leftBound + rightBound) / 2;
-            if (!TryExecutableTransaction(tx, header, mid, token))
+            if (!TryExecutableTransaction(tx, header, mid, token, gasTracer))
             {
                 leftBound = mid;
             }
@@ -116,59 +134,37 @@ private long BinarySearchEstimate(long leftBound, long rightBound, Transaction t
             }
         }
 
-        if (rightBound == cap && !TryExecutableTransaction(tx, header, rightBound, token))
+        if (rightBound == cap && !TryExecutableTransaction(tx, header, rightBound, token, gasTracer))
         {
+            // Set error based on failure reason
+            if (gasTracer.OutOfGas)
+            {
+                err = "Gas estimation failed due to out of gas";
+            }
+            else if (gasTracer.StatusCode == StatusCode.Failure)
+            {
+                err = gasTracer.Error ?? "Transaction execution fails";
+            }
+            else
+            {
+                err = "Transaction execution fails";
+            }
             return 0;
         }
 
         return rightBound;
     }
 
     private bool TryExecutableTransaction(Transaction transaction, BlockHeader block, long gasLimit,
-        CancellationToken token)
+        CancellationToken token, EstimateGasTracer gasTracer)
     {
-        OutOfGasTracer tracer = new();
-
         Transaction txClone = new Transaction();
         transaction.CopyTo(txClone);
         txClone.GasLimit = gasLimit;
 
         _transactionProcessor.SetBlockExecutionContext(new(block, _specProvider.GetSpec(block)));
-        _transactionProcessor.CallAndRestore(txClone, tracer.WithCancellation(token));
-
-        return !tracer.OutOfGas;
-    }
-
-    private class OutOfGasTracer : TxTracer
-    {
-        public OutOfGasTracer()
-        {
-            OutOfGas = false;
-        }
-
-        public override bool IsTracingReceipt => true;
-        public override bool IsTracingInstructions => true;
-        public override bool IsTracingActions => true;
-        public bool OutOfGas { get; private set; }
+        TransactionResult result = _transactionProcessor.CallAndRestore(txClone, gasTracer.WithCancellation(token));
 
-        public override void MarkAsSuccess(Address recipient, GasConsumed gasSpent, byte[] output, LogEntry[] logs,
-            Hash256? stateRoot = null)
-        {
-        }
-
-        public override void MarkAsFailed(Address recipient, GasConsumed gasSpent, byte[] output, string? error,
-            Hash256? stateRoot = null)
-        {
-        }
-
-        public override void ReportActionError(EvmExceptionType error)
-        {
-            OutOfGas |= error == EvmExceptionType.OutOfGas;
-        }
-
-        public override void ReportOperationError(EvmExceptionType error)
-        {
-            OutOfGas |= error == EvmExceptionType.OutOfGas;
-        }
+        return result.TransactionExecuted && gasTracer.StatusCode == StatusCode.Success && !gasTracer.OutOfGas;
     }
 }