test(evm): split evmante handlers 1 handler 1 file

app/evmante_can_transfer.go

@@ -0,0 +1,94 @@
+// Copyright (c) 2023-2024 Nibi, Inc.
+package app
+
+import (
+	"math/big"
+
+	"cosmossdk.io/errors"
+	sdk "github.com/cosmos/cosmos-sdk/types"
+	errortypes "github.com/cosmos/cosmos-sdk/types/errors"
+
+	"github.com/NibiruChain/nibiru/x/evm"
+	"github.com/NibiruChain/nibiru/x/evm/statedb"
+
+	gethcommon "github.com/ethereum/go-ethereum/common"
+	gethcore "github.com/ethereum/go-ethereum/core/types"
+)
+
+// CanTransferDecorator checks if the sender is allowed to transfer funds according to the EVM block
+// context rules.
+type CanTransferDecorator struct {
+	AppKeepers
+}
+
+// NewCanTransferDecorator creates a new CanTransferDecorator instance.
+func NewCanTransferDecorator(k AppKeepers) CanTransferDecorator {
+	return CanTransferDecorator{
+		AppKeepers: k,
+	}
+}
+
+// AnteHandle creates an EVM from the message and calls the BlockContext CanTransfer function to
+// see if the address can execute the transaction.
+func (ctd CanTransferDecorator) AnteHandle(
+	ctx sdk.Context, tx sdk.Tx, simulate bool, next sdk.AnteHandler,
+) (sdk.Context, error) {
+	params := ctd.EvmKeeper.GetParams(ctx)
+	ethCfg := evm.EthereumConfig(ctd.EvmKeeper.EthChainID(ctx))
+	signer := gethcore.MakeSigner(ethCfg, big.NewInt(ctx.BlockHeight()))
+
+	for _, msg := range tx.GetMsgs() {
+		msgEthTx, ok := msg.(*evm.MsgEthereumTx)
+		if !ok {
+			return ctx, errors.Wrapf(errortypes.ErrUnknownRequest, "invalid message type %T, expected %T", msg, (*evm.MsgEthereumTx)(nil))
+		}
+
+		baseFee := ctd.EvmKeeper.GetBaseFee(ctx)
+
+		coreMsg, err := msgEthTx.AsMessage(signer, baseFee)
+		if err != nil {
+			return ctx, errors.Wrapf(
+				err,
+				"failed to create an ethereum core.Message from signer %T", signer,
+			)
+		}
+
+		if baseFee == nil {
+			return ctx, errors.Wrap(
+				evm.ErrInvalidBaseFee,
+				"base fee is supported but evm block context value is nil",
+			)
+		}
+		if coreMsg.GasFeeCap().Cmp(baseFee) < 0 {
+			return ctx, errors.Wrapf(
+				errortypes.ErrInsufficientFee,
+				"max fee per gas less than block base fee (%s < %s)",
+				coreMsg.GasFeeCap(), baseFee,
+			)
+		}
+
+		// NOTE: pass in an empty coinbase address and nil tracer as we don't need them for the check below
+		cfg := &statedb.EVMConfig{
+			ChainConfig: ethCfg,
+			Params:      params,
+			CoinBase:    gethcommon.Address{},
+			BaseFee:     baseFee,
+		}
+
+		stateDB := statedb.New(ctx, &ctd.EvmKeeper, statedb.NewEmptyTxConfig(gethcommon.BytesToHash(ctx.HeaderHash().Bytes())))
+		evm := ctd.EvmKeeper.NewEVM(ctx, coreMsg, cfg, evm.NewNoOpTracer(), stateDB)
+
+		// check that caller has enough balance to cover asset transfer for **topmost** call
+		// NOTE: here the gas consumed is from the context with the infinite gas meter
+		if coreMsg.Value().Sign() > 0 && !evm.Context.CanTransfer(stateDB, coreMsg.From(), coreMsg.Value()) {
+			return ctx, errors.Wrapf(
+				errortypes.ErrInsufficientFunds,
+				"failed to transfer %s from address %s using the EVM block context transfer function",
+				coreMsg.Value(),
+				coreMsg.From(),
+			)
+		}
+	}
+
+	return next(ctx, tx, simulate)
+}