fix(evm): The estimated gas and the gas used for executing the message are not consistent

CHANGELOG.md

@@ -62,6 +62,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 ### Bug Fixes
 
 - (evm) [#1801](https://github.com/evmos/evmos/pull/1801) Fixed the problem gas_used is 0 when using evm type tx to transfer token to module account.
+- (evm) [#1943](https://github.com/evmos/evmos/pull/1943) Fix gas estimation (`eth_estimateGas`) to be consistent with gas used in EVM extensions transactions
 
 ## [v15.0.0] - 2023-10-31
 

tests/nix_tests/test_osmosis_outpost.py

@@ -56,7 +56,7 @@ def test_ibc_transfer(ibc):
 
     assert receipt.status == 1
     # check gas used
-    assert receipt.gasUsed == 133680
+    assert receipt.gasUsed == 74092
 
     fee = receipt.gasUsed * evmos_gas_price
 

tests/nix_tests/test_precompiles.py

@@ -53,7 +53,7 @@ def test_ibc_transfer(ibc):
 
     assert receipt.status == 1
     # check gas used
-    assert receipt.gasUsed == 133680
+    assert receipt.gasUsed == 74092
 
     fee = receipt.gasUsed * evmos_gas_price
 

x/erc20/keeper/evm.go

@@ -186,10 +186,10 @@ func (k Keeper) CallEVMWithData(
 			return nil, errorsmod.Wrapf(errortypes.ErrJSONMarshal, "failed to marshal tx args: %s", err.Error())
 		}
 
-		gasRes, err := k.evmKeeper.EstimateGas(sdk.WrapSDKContext(ctx), &evmtypes.EthCallRequest{
+		gasRes, err := k.evmKeeper.EstimateGasInternal(sdk.WrapSDKContext(ctx), &evmtypes.EthCallRequest{
 			Args:   args,
 			GasCap: config.DefaultGasCap,
-		})
+		}, evmtypes.Internal)
 		if err != nil {
 			return nil, err
 		}

x/erc20/keeper/evm_test.go

@@ -251,15 +251,15 @@ func (suite *KeeperTestSuite) TestForceFail() {
 		{
 			"Force estimate gas error",
 			func() {
-				mockEVMKeeper.On("EstimateGas", mock.Anything, mock.Anything).Return(nil, fmt.Errorf("forced EstimateGas error"))
+				mockEVMKeeper.On("EstimateGasInternal", mock.Anything, mock.Anything, mock.Anything).Return(nil, fmt.Errorf("forced EstimateGas error"))
 			},
 			true,
 			false,
 		},
 		{
 			"Force ApplyMessage error",
 			func() {
-				mockEVMKeeper.On("EstimateGas", mock.Anything, mock.Anything).Return(&evmtypes.EstimateGasResponse{Gas: uint64(200)}, nil)
+				mockEVMKeeper.On("EstimateGasInternal", mock.Anything, mock.Anything, mock.Anything).Return(&evmtypes.EstimateGasResponse{Gas: uint64(200)}, nil)
 				mockEVMKeeper.On("ApplyMessage", mock.Anything, mock.Anything, mock.Anything, mock.Anything).Return(nil, fmt.Errorf("forced ApplyMessage error"))
 			},
 			true,
@@ -268,7 +268,7 @@ func (suite *KeeperTestSuite) TestForceFail() {
 		{
 			"Force ApplyMessage failed",
 			func() {
-				mockEVMKeeper.On("EstimateGas", mock.Anything, mock.Anything).Return(&evmtypes.EstimateGasResponse{Gas: uint64(200)}, nil)
+				mockEVMKeeper.On("EstimateGasInternal", mock.Anything, mock.Anything, mock.Anything).Return(&evmtypes.EstimateGasResponse{Gas: uint64(200)}, nil)
 				mockEVMKeeper.On("ApplyMessage", mock.Anything, mock.Anything, mock.Anything, mock.Anything).Return(&evmtypes.MsgEthereumTxResponse{VmError: "SomeError"}, nil)
 			},
 			true,

x/erc20/keeper/mock_test.go

@@ -33,8 +33,8 @@ func (m *MockEVMKeeper) GetAccountWithoutBalance(_ sdk.Context, _ common.Address
 	return args.Get(0).(*statedb.Account)
 }
 
-func (m *MockEVMKeeper) EstimateGas(_ context.Context, _ *evm.EthCallRequest) (*evm.EstimateGasResponse, error) {
-	args := m.Called(mock.Anything, mock.Anything)
+func (m *MockEVMKeeper) EstimateGasInternal(_ context.Context, _ *evm.EthCallRequest, _ evm.CallType) (*evm.EstimateGasResponse, error) {
+	args := m.Called(mock.Anything, mock.Anything, mock.Anything)
 	if args.Get(0) == nil {
 		return nil, args.Error(1)
 	}

x/erc20/keeper/proposals_test.go

@@ -208,7 +208,7 @@ func (suite KeeperTestSuite) TestRegisterCoin() { //nolint:govet // we can copy
 					authtypes.NewModuleAddress(govtypes.ModuleName), suite.app.AccountKeeper,
 					suite.app.BankKeeper, mockEVMKeeper, suite.app.StakingKeeper, suite.app.ClaimsKeeper)
 
-				mockEVMKeeper.On("EstimateGas", mock.Anything, mock.Anything).Return(&evmtypes.EstimateGasResponse{Gas: uint64(200)}, nil)
+				mockEVMKeeper.On("EstimateGasInternal", mock.Anything, mock.Anything, mock.Anything).Return(&evmtypes.EstimateGasResponse{Gas: uint64(200)}, nil)
 				mockEVMKeeper.On("ApplyMessage", mock.Anything, mock.Anything, mock.Anything, mock.Anything).Return(nil, fmt.Errorf("forced ApplyMessage error"))
 			},
 			false,
@@ -298,7 +298,7 @@ func (suite KeeperTestSuite) TestRegisterERC20() { //nolint:govet // we can copy
 					authtypes.NewModuleAddress(govtypes.ModuleName), suite.app.AccountKeeper,
 					suite.app.BankKeeper, mockEVMKeeper, suite.app.StakingKeeper, suite.app.ClaimsKeeper)
 
-				mockEVMKeeper.On("EstimateGas", mock.Anything, mock.Anything).Return(&evmtypes.EstimateGasResponse{Gas: uint64(200)}, nil)
+				mockEVMKeeper.On("EstimateGasInternal", mock.Anything, mock.Anything, mock.Anything).Return(&evmtypes.EstimateGasResponse{Gas: uint64(200)}, nil)
 				mockEVMKeeper.On("ApplyMessage", mock.Anything, mock.Anything, mock.Anything, mock.Anything).Return(nil, fmt.Errorf("forced ApplyMessage error"))
 			},
 			false,

x/erc20/types/interfaces.go

@@ -51,7 +51,7 @@ type StakingKeeper interface {
 type EVMKeeper interface {
 	GetParams(ctx sdk.Context) evmtypes.Params
 	GetAccountWithoutBalance(ctx sdk.Context, addr common.Address) *statedb.Account
-	EstimateGas(c context.Context, req *evmtypes.EthCallRequest) (*evmtypes.EstimateGasResponse, error)
+	EstimateGasInternal(c context.Context, req *evmtypes.EthCallRequest, fromType evmtypes.CallType) (*evmtypes.EstimateGasResponse, error)
 	ApplyMessage(ctx sdk.Context, msg core.Message, tracer vm.EVMLogger, commit bool) (*evmtypes.MsgEthereumTxResponse, error)
 }
 

x/evm/keeper/grpc_query.go

@@ -10,6 +10,8 @@
 	"math/big"
 	"time"
 
+	storetypes "github.com/cosmos/cosmos-sdk/store/types"
+
 	"github.com/ethereum/go-ethereum/eth/tracers"
 	"github.com/ethereum/go-ethereum/eth/tracers/logger"
 
@@ -256,6 +258,16 @@
 
 // EstimateGas implements eth_estimateGas rpc api.
 func (k Keeper) EstimateGas(c context.Context, req *types.EthCallRequest) (*types.EstimateGasResponse, error) {
+	return k.EstimateGasInternal(c, req, types.RPC)
+}
+
+// EstimateGasInternal returns the gas estimation for the corresponding request.
+// This function is called from the RPC client (eth_estimateGas) and internally
+// by the CallEVMWithData function in the x/erc20 module keeper.
+// When called from the RPC client, we need to reset the gas meter before
+// simulating the transaction to have
+// an accurate gas estimation for EVM extensions transactions
+func (k Keeper) EstimateGasInternal(c context.Context, req *types.EthCallRequest, fromType types.CallType) (*types.EstimateGasResponse, error) {
 	if req == nil {
 		return nil, status.Error(codes.InvalidArgument, "empty request")
 	}
@@ -267,7 +279,7 @@
 	}
 
 	if req.GasCap < ethparams.TxGas {
-		return nil, status.Error(codes.InvalidArgument, "gas cap cannot be lower than 21,000")
+		return nil, status.Errorf(codes.InvalidArgument, "gas cap cannot be lower than %d", ethparams.TxGas)
 	}
 
 	var args types.TransactionArgs
@@ -341,8 +353,30 @@
 			msg.IsFake(),
 		)
 
+		tmpCtx := ctx
+		if fromType == types.RPC {
+			tmpCtx, _ = ctx.CacheContext()
+
+			acct := k.GetAccount(tmpCtx, msg.From())
+
+			from := msg.From()
+			if acct == nil {
+				acc := k.accountKeeper.NewAccountWithAddress(tmpCtx, from[:])
+				k.accountKeeper.SetAccount(tmpCtx, acc)
+				acct = statedb.NewEmptyAccount()
+			}
+			// When submitting a transaction, the `EthIncrementSenderSequence` ante handler increases the account nonce
+			acct.Nonce = nonce + 1
+			err = k.SetAccount(tmpCtx, from, *acct)
+			if err != nil {
+				return true, nil, err
+			}
+			// resetting the gasMeter after increasing the sequence to have an accurate gas estimation on EVM extensions transactions
+			tmpCtx = tmpCtx.WithGasMeter(evmostypes.NewInfiniteGasMeterWithLimit(msg.Gas())).WithKVGasConfig(storetypes.GasConfig{}).
+				WithTransientKVGasConfig(storetypes.GasConfig{})
+		}
 		// pass false to not commit StateDB
-		rsp, err = k.ApplyMessageWithConfig(ctx, msg, nil, false, cfg, txConfig)
+		rsp, err = k.ApplyMessageWithConfig(tmpCtx, msg, nil, false, cfg, txConfig)
 		if err != nil {
 			if errors.Is(err, core.ErrIntrinsicGas) {
 				return true, nil, nil // Special case, raise gas limit

x/evm/types/call.go

@@ -0,0 +1,12 @@
+// Copyright Tharsis Labs Ltd.(Evmos)
+// SPDX-License-Identifier:ENCL-1.0(https://github.com/evmos/evmos/blob/main/LICENSE)
+package types
+
+type CallType int
+
+const (
+	// RPC call type is used on requests to eth_estimateGas rpc API endpoint
+	RPC CallType = iota + 1
+	// Internal call type is used in case of smart contract methods calls
+	Internal
+)