fix: use snapshot to support revert (#90)

* use snapshot to support revert

* add test for call revert

x/evm/contracts/counter/Counter.sol

@@ -37,6 +37,17 @@ contract Counter is IIBCAsyncCallback {
         return COSMOS_CONTRACT.query_cosmos(path, req);
     }
 
+    function execute_cosmos(
+        string memory exec_msg,
+        bool call_revert
+    ) external {
+        COSMOS_CONTRACT.execute_cosmos(exec_msg);
+
+        if (call_revert) {
+            revert("revert");
+        }
+    }
+
     function get_blockhash(uint64 n) external view returns (bytes32) {
         return blockhash(n);
     }

x/evm/keeper/context.go

@@ -161,6 +161,12 @@ func (k Keeper) CreateEVM(ctx context.Context, caller common.Address, tracer *tr
 		return ctx, nil, err
 	}
 
+	// prepare SDK context for EVM execution
+	ctx, err = prepareSDKContext(sdk.UnwrapSDKContext(ctx))
+	if err != nil {
+		return ctx, nil, err
+	}
+
 	evm := &vm.EVM{}
 	blockContext, err := k.buildBlockContext(ctx, evm, fee)
 	if err != nil {
@@ -181,19 +187,13 @@ func (k Keeper) CreateEVM(ctx context.Context, caller common.Address, tracer *tr
 		NumRetainBlockHashes: &params.NumRetainBlockHashes,
 	}
 
-	// prepare SDK context for EVM execution
-	ctx, err = prepareSDKContext(sdk.UnwrapSDKContext(ctx))
-	if err != nil {
-		return ctx, nil, err
-	}
-
 	*evm = *vm.NewEVMWithPrecompiles(
 		blockContext,
 		txContext,
 		stateDB,
 		types.DefaultChainConfig(ctx),
 		vmConfig,
-		k.precompiles.toMap(ctx),
+		k.precompiles.toMap(stateDB),
 	)
 
 	if tracer != nil {

x/evm/keeper/context_test.go

@@ -1,6 +1,7 @@
 package keeper_test
 
 import (
+	"fmt"
 	"strings"
 	"testing"
 
@@ -237,3 +238,63 @@ func Test_RecursiveDepth(t *testing.T) {
 	_, _, err = input.EVMKeeper.EVMCall(ctx, caller, contractAddr, inputBz, nil, nil)
 	require.ErrorContains(t, err, types.ErrExceedMaxRecursiveDepth.Error())
 }
+
+func Test_RevertAfterExecuteCosmos(t *testing.T) {
+	ctx, input := createDefaultTestInput(t)
+	_, _, addr := keyPubAddr()
+
+	counterBz, err := hexutil.Decode(counter.CounterBin)
+	require.NoError(t, err)
+
+	// deploy counter contract
+	caller := common.BytesToAddress(addr.Bytes())
+	retBz, contractAddr, _, err := input.EVMKeeper.EVMCreate(ctx, caller, counterBz, nil, nil)
+	require.NoError(t, err)
+	require.NotEmpty(t, retBz)
+	require.Len(t, contractAddr, 20)
+
+	// call execute cosmos function
+	parsed, err := counter.CounterMetaData.GetAbi()
+	require.NoError(t, err)
+
+	denom := sdk.DefaultBondDenom
+	amount := math.NewInt(1000000000)
+	input.Faucet.Mint(ctx, contractAddr.Bytes(), sdk.NewCoin(denom, amount))
+
+	// call execute_cosmos with revert
+	inputBz, err := parsed.Pack("execute_cosmos",
+		fmt.Sprintf(`{"@type":"/cosmos.bank.v1beta1.MsgSend","from_address":"%s","to_address":"%s","amount":[{"denom":"%s","amount":"%s"}]}`,
+			sdk.AccAddress(contractAddr.Bytes()).String(),
+			addr.String(), // caller
+			denom,
+			amount,
+		),
+		true,
+	)
+	require.NoError(t, err)
+
+	_, _, err = input.EVMKeeper.EVMCall(ctx, caller, contractAddr, inputBz, nil, nil)
+	require.ErrorContains(t, err, types.ErrReverted.Error())
+
+	// check balance
+	require.Equal(t, amount, input.BankKeeper.GetBalance(ctx, sdk.AccAddress(contractAddr.Bytes()), denom).Amount)
+	require.Equal(t, math.ZeroInt(), input.BankKeeper.GetBalance(ctx, addr, denom).Amount)
+
+	// call execute_cosmos without revert
+	inputBz, err = parsed.Pack("execute_cosmos",
+		fmt.Sprintf(`{"@type":"/cosmos.bank.v1beta1.MsgSend","from_address":"%s","to_address":"%s","amount":[{"denom":"%s","amount":"%s"}]}`,
+			sdk.AccAddress(contractAddr.Bytes()).String(),
+			addr.String(), // caller
+			denom,
+			amount,
+		),
+		false,
+	)
+	require.NoError(t, err)
+
+	_, _, err = input.EVMKeeper.EVMCall(ctx, caller, contractAddr, inputBz, nil, nil)
+	require.NoError(t, err, types.ErrReverted.Error())
+
+	require.Equal(t, math.ZeroInt(), input.BankKeeper.GetBalance(ctx, sdk.AccAddress(contractAddr.Bytes()), denom).Amount)
+	require.Equal(t, amount, input.BankKeeper.GetBalance(ctx, addr, denom).Amount)
+}

x/evm/keeper/precompiles.go

@@ -1,8 +1,6 @@
 package keeper
 
 import (
-	"context"
-
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core/vm"
 
@@ -55,10 +53,10 @@ func (k *Keeper) loadPrecompiles() error {
 type precompiles []precompile
 
 // toMap converts the precompiles to a map.
-func (ps precompiles) toMap(ctx context.Context) map[common.Address]vm.PrecompiledContract {
+func (ps precompiles) toMap(stateDB types.StateDB) map[common.Address]vm.PrecompiledContract {
 	m := make(map[common.Address]vm.PrecompiledContract)
 	for _, p := range ps {
-		m[p.addr] = p.contract.(types.WithContext).WithContext(ctx)
+		m[p.addr] = p.contract.(types.WithStateDB).WithStateDB(stateDB)
 	}
 
 	return m