add evm min fee e2e tests (#1521)

* parse min gas price from app.toml

* test eth_gasPrice returns min fee

* use naming best practices for custom errors

* add test that evm respects min gas price

* update kvtool

* increase ibc test wait time & update kvtool

tests/e2e/e2e_min_fees_test.go

@@ -0,0 +1,73 @@
+package e2e_test
+
+import (
+	"context"
+	"math/big"
+	"os"
+	"path/filepath"
+	"strings"
+
+	"github.com/pelletier/go-toml/v2"
+
+	sdk "github.com/cosmos/cosmos-sdk/types"
+	ethtypes "github.com/ethereum/go-ethereum/core/types"
+
+	"github.com/kava-labs/kava/app"
+	"github.com/kava-labs/kava/tests/util"
+)
+
+func (suite *IntegrationTestSuite) TestEthGasPriceReturnsMinFee() {
+	// read expected min fee from app.toml
+	minGasPrices, err := getMinFeeFromAppToml(suite.KavaHomePath())
+	suite.NoError(err)
+
+	// evm uses akava, get akava min fee
+	evmMinGas := minGasPrices.AmountOf("akava").TruncateInt().BigInt()
+
+	// returns eth_gasPrice, units in kava
+	gasPrice, err := suite.Kava.EvmClient.SuggestGasPrice(context.Background())
+	suite.NoError(err)
+
+	suite.Equal(evmMinGas, gasPrice)
+}
+
+func (suite *IntegrationTestSuite) TestEvmRespectsMinFee() {
+	// setup sender & receiver
+	sender := suite.Kava.NewFundedAccount("evm-min-fee-test-sender", sdk.NewCoins(ukava(2e6)))
+	randoReceiver := util.SdkToEvmAddress(app.RandomAddress())
+
+	// get min gas price for evm (from app.toml)
+	minFees, err := getMinFeeFromAppToml(suite.KavaHomePath())
+	suite.NoError(err)
+	minGasPrice := minFees.AmountOf("akava").TruncateInt()
+
+	// attempt tx with less than min gas price (min fee - 1)
+	tooLowGasPrice := minGasPrice.Sub(sdk.OneInt()).BigInt()
+	req := util.EvmTxRequest{
+		Tx:   ethtypes.NewTransaction(0, randoReceiver, big.NewInt(1e6), 1e5, tooLowGasPrice, nil),
+		Data: "this tx should fail because it's gas price is too low",
+	}
+	res := sender.SignAndBroadcastEvmTx(req)
+
+	// expect the tx to fail!
+	suite.ErrorAs(res.Err, &util.ErrEvmFailedToBroadcast{})
+	suite.ErrorContains(res.Err, "insufficient fees")
+}
+
+func getMinFeeFromAppToml(kavaHome string) (sdk.DecCoins, error) {
+	// read the expected min gas price from app.toml
+	parsed := struct {
+		MinGasPrices string `toml:"minimum-gas-prices"`
+	}{}
+	appToml, err := os.ReadFile(filepath.Join(kavaHome, "config", "app.toml"))
+	if err != nil {
+		return nil, err
+	}
+	err = toml.Unmarshal(appToml, &parsed)
+	if err != nil {
+		return nil, err
+	}
+
+	// convert to dec coins
+	return sdk.ParseDecCoins(strings.ReplaceAll(parsed.MinGasPrices, ";", ","))
+}

tests/e2e/e2e_test.go

@@ -170,5 +170,5 @@ func (suite *IntegrationTestSuite) TestIbcTransfer() {
 			}
 		}
 		return found
-	}, 10*time.Second, 1*time.Second)
+	}, 15*time.Second, 1*time.Second)
 }

tests/e2e/kvtool

@@ -1 +1 @@
-Subproject commit 8adc0437e849f86bdcb2df3833abbfbd0980775e
+Subproject commit 8153036b95a930c7830c6969d1653165afa65f2c

tests/e2e/testutil/suite.go

@@ -2,6 +2,7 @@ package testutil
 
 import (
 	"fmt"
+	"path/filepath"
 
 	"github.com/stretchr/testify/suite"
 
@@ -96,3 +97,9 @@ func (suite *E2eTestSuite) SkipIfUpgradeDisabled() {
 		suite.T().SkipNow()
 	}
 }
+
+// KavaHomePath returns the OS-specific filepath for the kava home directory
+// Assumes network is running with kvtool installed from the sub-repository in tests/e2e/kvtool
+func (suite *E2eTestSuite) KavaHomePath() string {
+	return filepath.Join("kvtool", "full_configs", "generated", "kava", "initstate", ".kava")
+}

tests/util/evmsigner.go

@@ -23,15 +23,15 @@ type EvmTxResponse struct {
 	Err     error
 }
 
-type EvmFailedToSignError struct{ Err error }
+type ErrEvmFailedToSign struct{ Err error }
 
-func (e EvmFailedToSignError) Error() string {
+func (e ErrEvmFailedToSign) Error() string {
 	return fmt.Sprintf("failed to sign tx: %s", e.Err)
 }
 
-type EvmFailedToBroadcastError struct{ Err error }
+type ErrEvmFailedToBroadcast struct{ Err error }
 
-func (e EvmFailedToBroadcastError) Error() string {
+func (e ErrEvmFailedToBroadcast) Error() string {
 	return fmt.Sprintf("failed to broadcast tx: %s", e.Err)
 }
 
@@ -79,11 +79,11 @@ func (s *EvmSigner) Run(requests <-chan EvmTxRequest) <-chan EvmTxResponse {
 
 			signedTx, err := s.auth.Signer(s.signerAddress, req.Tx)
 			if err != nil {
-				err = EvmFailedToSignError{Err: err}
+				err = ErrEvmFailedToSign{Err: err}
 			} else {
 				err = s.EvmClient.SendTransaction(context.Background(), signedTx)
 				if err != nil {
-					err = EvmFailedToBroadcastError{Err: err}
+					err = ErrEvmFailedToBroadcast{Err: err}
 				}
 			}