fix(rpc): add revert reason for eth_estimateGas

CHANGELOG.md

@@ -38,6 +38,11 @@ Ref: https://keepachangelog.com/en/1.0.0/
 
 ## Unreleased
 
+### Bug Fixes
+
+* (rpc) [#1722](https://github.com/evmos/ethermint/pull/1722) Align revert response for `eth_estimateGas` and `eth_call` as Ethereum.
+
+
 ### State Machine Breaking
 
 * (deps) [#1168](https://github.com/evmos/ethermint/pull/1168) Upgrade Cosmos SDK to [`v0.46.6`]

proto/ethermint/evm/v1/query.proto

@@ -231,6 +231,11 @@ message EthCallRequest {
 message EstimateGasResponse {
   // gas returns the estimated gas
   uint64 gas = 1;
+  // ret is the returned data from evm function (result or data supplied with revert
+  // opcode)
+  bytes ret = 2;
+  // vm_error is the error returned by vm execution
+  string vm_error = 3;
 }
 
 // QueryTraceTxRequest defines TraceTx request

rpc/backend/call_tx.go

@@ -304,6 +304,20 @@ func (b *Backend) SetTxDefaults(args evmtypes.TransactionArgs) (evmtypes.Transac
 	return args, nil
 }
 
+// handleRevertError returns revert related error.
+func (b *Backend) handleRevertError(vmError string, ret []byte) error {
+	if len(vmError) > 0 {
+		if vmError != vm.ErrExecutionReverted.Error() {
+			return status.Error(codes.Internal, vmError)
+		}
+		if len(ret) == 0 {
+			return errors.New(vmError)
+		}
+		return evmtypes.NewExecErrorWithReason(ret)
+	}
+	return nil
+}
+
 // EstimateGas returns an estimate of gas usage for the given smart contract call.
 func (b *Backend) EstimateGas(args evmtypes.TransactionArgs, blockNrOptional *rpctypes.BlockNumber) (hexutil.Uint64, error) {
 	blockNr := rpctypes.EthPendingBlockNumber
@@ -336,6 +350,9 @@ func (b *Backend) EstimateGas(args evmtypes.TransactionArgs, blockNrOptional *rp
 	if err != nil {
 		return 0, err
 	}
+	if err = b.handleRevertError(res.VmError, res.Ret); err != nil {
+		return 0, err
+	}
 	return hexutil.Uint64(res.Gas), nil
 }
 
@@ -385,13 +402,9 @@ func (b *Backend) DoCall(
 		return nil, err
 	}
 
-	if res.Failed() {
-		if res.VmError != vm.ErrExecutionReverted.Error() {
-			return nil, status.Error(codes.Internal, res.VmError)
-		}
-		return nil, evmtypes.NewExecErrorWithReason(res.Ret)
+	if err = b.handleRevertError(res.VmError, res.Ret); err != nil {
+		return nil, err
 	}
-
 	return res, nil
 }
 

tests/integration_tests/hardhat/contracts/TestRevert.sol

@@ -0,0 +1,14 @@
+// SPDX-License-Identifier: MIT
+pragma solidity 0.8.10;
+
+contract TestRevert {
+    // 0x9ffb86a5
+    function revertWithMsg() public pure {
+        revert("Function has been reverted");
+    }
+
+    // 0x3246485d
+    function revertWithoutMsg() public pure {
+        revert();
+    }
+}

tests/integration_tests/test_estimate_gas.py

@@ -0,0 +1,50 @@
+import pytest
+
+from .network import setup_ethermint
+from .utils import ADDRS, CONTRACTS, deploy_contract
+
+
+@pytest.fixture(scope="module")
+def custom_ethermint(tmp_path_factory):
+    path = tmp_path_factory.mktemp("estimate-gas")
+    yield from setup_ethermint(path, 27010, long_timeout_commit=True)
+
+
+@pytest.fixture(scope="module", params=["ethermint", "geth"])
+def cluster(request, custom_ethermint, geth):
+    """
+    run on both ethermint and geth
+    """
+    provider = request.param
+    if provider == "ethermint":
+        yield custom_ethermint
+    elif provider == "geth":
+        yield geth
+    else:
+        raise NotImplementedError
+
+
+def test_revert(cluster):
+    w3 = cluster.w3
+    call = w3.provider.make_request
+    validator = ADDRS["validator"]
+    erc20, _ = deploy_contract(
+        w3,
+        CONTRACTS["TestRevert"],
+    )
+    method = "eth_estimateGas"
+
+    def do_call(data):
+        params = {"from": validator, "to": erc20.address, "data": data}
+        return call(method, [params])["error"]
+
+    # revertWithMsg
+    error = do_call("0x9ffb86a5")
+    assert error["code"] == 3
+    assert error["message"] == "execution reverted: Function has been reverted"
+    assert (error["data"] == "0x08c379a00000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000001a46756e6374696f6e20686173206265656e207265766572746564000000000000")  # noqa: E501
+
+    # revertWithoutMsg
+    error = do_call("0x3246485d")
+    assert error["code"] == -32000
+    assert error["message"] == "execution reverted"

tests/integration_tests/utils.py

@@ -32,6 +32,7 @@
     "TestChainID": "ChainID.sol",
     "Mars": "Mars.sol",
     "StateContract": "StateContract.sol",
+    "TestRevert": "TestRevert.sol",
 }
 
 

x/evm/keeper/grpc_query.go

@@ -379,7 +379,10 @@ func (k Keeper) EstimateGas(c context.Context, req *types.EthCallRequest) (*type
 		if failed {
 			if result != nil && result.VmError != vm.ErrOutOfGas.Error() {
 				if result.VmError == vm.ErrExecutionReverted.Error() {
-					return nil, types.NewExecErrorWithReason(result.Ret)
+					return &types.EstimateGasResponse{
+						Ret:     result.Ret,
+						VmError: result.VmError,
+					}, nil
 				}
 				return nil, errors.New(result.VmError)
 			}