Fix eth_gasPrice RPC method

jsonrpc/eth_blockchain_test.go

@@ -6,6 +6,7 @@ import (
 	"testing"
 
 	"github.com/0xPolygon/polygon-edge/blockchain"
+	"github.com/0xPolygon/polygon-edge/chain"
 	"github.com/0xPolygon/polygon-edge/helper/hex"
 	"github.com/0xPolygon/polygon-edge/helper/progress"
 	"github.com/0xPolygon/polygon-edge/state/runtime"
@@ -280,6 +281,11 @@ func TestEth_Syncing(t *testing.T) {
 func TestEth_GetPrice_PriceLimitSet(t *testing.T) {
 	priceLimit := uint64(100333)
 	store := newMockBlockStore()
+	store.blocks = []*types.Block{
+		{
+			Header: &types.Header{Number: uint64(1)},
+		},
+	}
 	// not using newTestEthEndpoint as we need to set priceLimit
 	eth := newTestEthEndpointWithPriceLimit(store, priceLimit)
 
@@ -306,6 +312,11 @@ func TestEth_GasPrice(t *testing.T) {
 	store := newMockBlockStore()
 	store.averageGasPrice = 9999
 	eth := newTestEthEndpoint(store)
+	store.blocks = []*types.Block{
+		{
+			Header: &types.Header{Number: uint64(1)},
+		},
+	}
 
 	res, err := eth.GasPrice()
 	assert.NoError(t, err)
@@ -598,6 +609,14 @@ func (m *mockBlockStore) GetAccount(root types.Hash, addr types.Address) (*Accou
 	return &Account{Nonce: 0}, nil
 }
 
+func (m *mockBlockStore) GetBaseFee() uint64 {
+	return 0
+}
+
+func (m *mockBlockStore) GetForksInTime(block uint64) chain.ForksInTime {
+	return chain.ForksInTime{London: false}
+}
+
 func newTestBlock(number uint64, hash types.Hash) *types.Block {
 	return &types.Block{
 		Header: &types.Header{

jsonrpc/eth_endpoint.go

@@ -26,6 +26,9 @@ type ethTxPoolStore interface {
 
 	// GetNonce returns the next nonce for this address
 	GetNonce(addr types.Address) uint64
+
+	// returns the current base fee of TxPool
+	GetBaseFee() uint64
 }
 
 type Account struct {
@@ -393,10 +396,19 @@ func (e *Eth) GetStorageAt(
 // GasPrice returns the average gas price based on the last x blocks
 // taking into consideration operator defined price limit
 func (e *Eth) GasPrice() (interface{}, error) {
+	// Return --price-limit flag defined value if it is greater than avgGasPrice/baseFee+priorityFee
+	if e.store.GetForksInTime(e.store.Header().Number).London {
+		priorityFee, err := e.store.MaxPriorityFeePerGas()
+		if err != nil {
+			return nil, err
+		}
+
+		return argUint64(common.Max(e.priceLimit, priorityFee.Uint64()+e.store.GetBaseFee())), nil
+	}
+
 	// Fetch average gas price in uint64
 	avgGasPrice := e.store.GetAvgGasPrice().Uint64()
 
-	// Return --price-limit flag defined value if it is greater than avgGasPrice
 	return argUint64(common.Max(e.priceLimit, avgGasPrice)), nil
 }