From 7da60cd2518c929713d274c3a3148ce487b608c0 Mon Sep 17 00:00:00 2001
From: HuangYi <huang@crypto.com>
Date: Mon, 11 Jul 2022 17:03:23 +0800
Subject: [PATCH] NewAnteHandler returns error if input not valid

make NewAnteHandler safer too use, and closer to cosmos-sdk api.
extracted from https://github.com/evmos/ethermint/pull/1168
---
 app/ante/ante.go            |  7 +++++--
 app/ante/handler_options.go |  2 +-
 app/ante/utils_test.go      |  9 ++++-----
 app/app.go                  | 10 ++++------
 4 files changed, 14 insertions(+), 14 deletions(-)

diff --git a/app/ante/ante.go b/app/ante/ante.go
index 94cc70289c..50fabbffdc 100644
--- a/app/ante/ante.go
+++ b/app/ante/ante.go
@@ -23,7 +23,10 @@ const (
 // Ethereum or SDK transaction to an internal ante handler for performing
 // transaction-level processing (e.g. fee payment, signature verification) before
 // being passed onto it's respective handler.
-func NewAnteHandler(options HandlerOptions) sdk.AnteHandler {
+func NewAnteHandler(options HandlerOptions) (sdk.AnteHandler, error) {
+	if err := options.validate(); err != nil {
+		return nil, err
+	}
 	return func(
 		ctx sdk.Context, tx sdk.Tx, sim bool,
 	) (newCtx sdk.Context, err error) {
@@ -62,7 +65,7 @@ func NewAnteHandler(options HandlerOptions) sdk.AnteHandler {
 		}
 
 		return anteHandler(ctx, tx, sim)
-	}
+	}, nil
 }
 
 func Recover(logger tmlog.Logger, err *error) {
diff --git a/app/ante/handler_options.go b/app/ante/handler_options.go
index 79271e3ddd..ec0e34ed47 100644
--- a/app/ante/handler_options.go
+++ b/app/ante/handler_options.go
@@ -28,7 +28,7 @@ type HandlerOptions struct {
 	MaxTxGasWanted  uint64
 }
 
-func (options HandlerOptions) Validate() error {
+func (options HandlerOptions) validate() error {
 	if options.AccountKeeper == nil {
 		return sdkerrors.Wrap(sdkerrors.ErrLogic, "account keeper is required for AnteHandler")
 	}
diff --git a/app/ante/utils_test.go b/app/ante/utils_test.go
index 5c030eb82d..b789f12882 100644
--- a/app/ante/utils_test.go
+++ b/app/ante/utils_test.go
@@ -105,7 +105,7 @@ func (suite *AnteTestSuite) SetupTest() {
 
 	suite.clientCtx = client.Context{}.WithTxConfig(encodingConfig.TxConfig)
 
-	options := ante.HandlerOptions{
+	anteHandler, err := ante.NewAnteHandler(ante.HandlerOptions{
 		AccountKeeper:   suite.app.AccountKeeper,
 		BankKeeper:      suite.app.BankKeeper,
 		EvmKeeper:       suite.app.EvmKeeper,
@@ -114,11 +114,10 @@ func (suite *AnteTestSuite) SetupTest() {
 		FeeMarketKeeper: suite.app.FeeMarketKeeper,
 		SignModeHandler: encodingConfig.TxConfig.SignModeHandler(),
 		SigGasConsumer:  ante.DefaultSigVerificationGasConsumer,
-	}
-
-	suite.Require().NoError(options.Validate())
+	})
+	suite.Require().NoError(err)
 
-	suite.anteHandler = ante.NewAnteHandler(options)
+	suite.anteHandler = anteHandler
 	suite.ethSigner = ethtypes.LatestSignerForChainID(suite.app.EvmKeeper.ChainID())
 }
 
diff --git a/app/app.go b/app/app.go
index c0acf7d426..b0a6f5455a 100644
--- a/app/app.go
+++ b/app/app.go
@@ -570,7 +570,7 @@ func NewEthermintApp(
 	// use Ethermint's custom AnteHandler
 
 	maxGasWanted := cast.ToUint64(appOpts.Get(srvflags.EVMMaxTxGasWanted))
-	options := ante.HandlerOptions{
+	anteHandler, err := ante.NewAnteHandler(ante.HandlerOptions{
 		AccountKeeper:   app.AccountKeeper,
 		BankKeeper:      app.BankKeeper,
 		EvmKeeper:       app.EvmKeeper,
@@ -580,13 +580,11 @@ func NewEthermintApp(
 		SignModeHandler: encodingConfig.TxConfig.SignModeHandler(),
 		SigGasConsumer:  ante.DefaultSigVerificationGasConsumer,
 		MaxTxGasWanted:  maxGasWanted,
-	}
-
-	if err := options.Validate(); err != nil {
+	})
+	if err != nil {
 		panic(err)
 	}
-
-	app.SetAnteHandler(ante.NewAnteHandler(options))
+	app.SetAnteHandler(anteHandler)
 	app.SetEndBlocker(app.EndBlocker)
 
 	if loadLatest {