add block limit error

Author: rjnrohit

src/Nethermind/Nethermind.JsonRpc/ErrorCodes.cs

@@ -111,5 +111,10 @@ public static class ErrorCodes
         /// Invalid RPC simulate call transaction
         /// </summary>
         public const int InvalidTransaction = -38014;
+
+        /// <summary>
+        /// Too many blocks for simulation
+        /// </summary>
+        public const int ClientLimitExceededError = -38026;
     }
 }

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

@@ -143,6 +143,11 @@ public override ResultWrapper<IReadOnlyList<SimulateBlockResult>> Execute(
                     return ResultWrapper<IReadOnlyList<SimulateBlockResult>>.Fail(
                         $"Block number out of order {givenNumber} is < than given base number of {header.Number}!", ErrorCodes.InvalidInputBlocksOutOfOrder);
 
+                // if the no. of filler blocks are greater than maximum simulate blocks cap
+                if (givenNumber - (ulong)lastBlockNumber > (ulong)_blocksLimit)
+                    return ResultWrapper<IReadOnlyList<SimulateBlockResult>>.Fail(
+                        $"too many blocks",
+                        ErrorCodes.ClientLimitExceededError);
 
                 for (ulong fillBlockNumber = (ulong)lastBlockNumber + 1; fillBlockNumber < givenNumber; fillBlockNumber++)
                 {