flashbots: Add baseFee to callBundle

Author: jparyani

internal/ethapi/api.go

@@ -2151,6 +2151,7 @@ type CallBundleArgs struct {
 	Timeout                *int64                `json:"timeout"`
 	GasLimit               *uint64               `json:"gasLimit"`
 	Difficulty             *big.Int              `json:"difficulty"`
+	BaseFee                *big.Int              `json:"baseFee"`
 }
 
 // CallBundle will simulate a bundle of transactions at the top of a given block
@@ -2205,13 +2206,20 @@ func (s *BundleAPI) CallBundle(ctx context.Context, args CallBundleArgs) (map[st
 	if args.GasLimit != nil {
 		gasLimit = *args.GasLimit
 	}
+	var baseFee *big.Int
+	if args.BaseFee != nil {
+		baseFee = args.BaseFee
+	} else if s.b.ChainConfig().IsLondon(big.NewInt(args.BlockNumber.Int64())) {
+		baseFee = misc.CalcBaseFee(s.b.ChainConfig(), parent)
+	}
 	header := &types.Header{
 		ParentHash: parent.Hash(),
 		Number:     blockNumber,
 		GasLimit:   gasLimit,
 		Time:       timestamp,
 		Difficulty: difficulty,
 		Coinbase:   coinbase,
+		BaseFee:    baseFee,
 	}
 
 	// Setup context so it may be cancelled the call has completed
@@ -2264,7 +2272,11 @@ func (s *BundleAPI) CallBundle(ctx context.Context, args CallBundleArgs) (map[st
 			"toAddress":   to,
 		}
 		totalGasUsed += receipt.GasUsed
-		gasFeesTx := new(big.Int).Mul(big.NewInt(int64(receipt.GasUsed)), tx.GasPrice())
+		gasPrice, err := tx.EffectiveGasTip(header.BaseFee)
+		if err != nil {
+			return nil, fmt.Errorf("err: %w; txhash %s", err, tx.Hash())
+		}
+		gasFeesTx := new(big.Int).Mul(big.NewInt(int64(receipt.GasUsed)), gasPrice)
 		gasFees.Add(gasFees, gasFeesTx)
 		bundleHash.Write(tx.Hash().Bytes())
 		if result.Err != nil {