error migration (#254)

* migrate errors

* ante handler errors

* return err instead of panic

app/ante/ante.go

@@ -7,7 +7,7 @@ import (
 	sdk "github.com/cosmos/cosmos-sdk/types"
 	sdkerrors "github.com/cosmos/cosmos-sdk/types/errors"
 	"github.com/cosmos/cosmos-sdk/x/auth"
-	"github.com/cosmos/cosmos-sdk/x/auth/ante"
+	authante "github.com/cosmos/cosmos-sdk/x/auth/ante"
 	"github.com/cosmos/cosmos-sdk/x/auth/types"
 
 	"github.com/cosmos/ethermint/crypto"
@@ -38,17 +38,17 @@ func NewAnteHandler(ak auth.AccountKeeper, sk types.SupplyKeeper) sdk.AnteHandle
 		switch castTx := tx.(type) {
 		case auth.StdTx:
 			stdAnte := sdk.ChainAnteDecorators(
-				ante.NewSetUpContextDecorator(), // outermost AnteDecorator. SetUpContext must be called first
-				ante.NewMempoolFeeDecorator(),
-				ante.NewValidateBasicDecorator(),
-				ante.NewValidateMemoDecorator(ak),
-				ante.NewConsumeGasForTxSizeDecorator(ak),
-				ante.NewSetPubKeyDecorator(ak), // SetPubKeyDecorator must be called before all signature verification decorators
-				ante.NewValidateSigCountDecorator(ak),
-				ante.NewDeductFeeDecorator(ak, sk),
-				ante.NewSigGasConsumeDecorator(ak, sigGasConsumer),
-				ante.NewSigVerificationDecorator(ak),
-				ante.NewIncrementSequenceDecorator(ak), // innermost AnteDecorator
+				authante.NewSetUpContextDecorator(), // outermost AnteDecorator. SetUpContext must be called first
+				authante.NewMempoolFeeDecorator(),
+				authante.NewValidateBasicDecorator(),
+				authante.NewValidateMemoDecorator(ak),
+				authante.NewConsumeGasForTxSizeDecorator(ak),
+				authante.NewSetPubKeyDecorator(ak), // SetPubKeyDecorator must be called before all signature verification decorators
+				authante.NewValidateSigCountDecorator(ak),
+				authante.NewDeductFeeDecorator(ak, sk),
+				authante.NewSigGasConsumeDecorator(ak, sigGasConsumer),
+				authante.NewSigVerificationDecorator(ak),
+				authante.NewIncrementSequenceDecorator(ak), // innermost AnteDecorator
 			)
 
 			return stdAnte(ctx, tx, sim)
@@ -57,7 +57,7 @@ func NewAnteHandler(ak auth.AccountKeeper, sk types.SupplyKeeper) sdk.AnteHandle
 			return ethAnteHandler(ctx, ak, sk, &castTx, sim)
 
 		default:
-			return ctx, sdk.ErrInternal(fmt.Sprintf("transaction type invalid: %T", tx))
+			return ctx, sdkerrors.Wrapf(sdkerrors.ErrUnknownRequest, "invalid transaction type: %T", tx)
 		}
 	}
 }
@@ -122,10 +122,11 @@ func ethAnteHandler(
 		if r := recover(); r != nil {
 			switch rType := r.(type) {
 			case sdk.ErrorOutOfGas:
-				log := fmt.Sprintf("out of gas in location: %v; gasUsed: %d",
+				err = sdkerrors.Wrapf(
+					sdkerrors.ErrOutOfGas,
+					"out of gas in location: %v; gasUsed: %d",
 					rType.Descriptor, ctx.GasMeter().GasConsumed(),
 				)
-				err = sdk.ErrOutOfGas(log)
 			default:
 				panic(r)
 			}
@@ -201,13 +202,13 @@ func validateSignature(ctx sdk.Context, ethTxMsg *evmtypes.MsgEthereumTx) (sdk.A
 	// parse the chainID from a string to a base-10 integer
 	chainID, ok := new(big.Int).SetString(ctx.ChainID(), 10)
 	if !ok {
-		return nil, emint.ErrInvalidChainID(fmt.Sprintf("invalid chainID: %s", ctx.ChainID()))
+		return nil, sdkerrors.Wrap(emint.ErrInvalidChainID, ctx.ChainID())
 	}
 
 	// validate sender/signature
 	signer, err := ethTxMsg.VerifySig(chainID)
 	if err != nil {
-		return nil, sdk.ErrUnauthorized(fmt.Sprintf("signature verification failed: %s", err))
+		return nil, sdkerrors.Wrap(err, "signature verification failed")
 	}
 
 	return sdk.AccAddress(signer.Bytes()), nil
@@ -221,12 +222,12 @@ func validateSignature(ctx sdk.Context, ethTxMsg *evmtypes.MsgEthereumTx) (sdk.A
 func validateIntrinsicGas(ethTxMsg *evmtypes.MsgEthereumTx) error {
 	gas, err := ethcore.IntrinsicGas(ethTxMsg.Data.Payload, ethTxMsg.To() == nil, true)
 	if err != nil {
-		return sdk.ErrInternal(fmt.Sprintf("failed to compute intrinsic gas cost: %s", err))
+		return sdkerrors.Wrap(err, "failed to compute intrinsic gas cost")
 	}
 
 	if ethTxMsg.Data.GasLimit < gas {
-		return sdk.ErrInternal(
-			fmt.Sprintf("intrinsic gas too low: %d < %d", ethTxMsg.Data.GasLimit, gas),
+		return fmt.Errorf(
+			"intrinsic gas too low: %d < %d", ethTxMsg.Data.GasLimit, gas,
 		)
 	}
 
@@ -243,10 +244,9 @@ func validateAccount(
 
 	// on InitChain make sure account number == 0
 	if ctx.BlockHeight() == 0 && acc.GetAccountNumber() != 0 {
-		return sdk.ErrInternal(
-			fmt.Sprintf(
-				"invalid account number for height zero (got %d)", acc.GetAccountNumber(),
-			),
+		return sdkerrors.Wrapf(
+			sdkerrors.ErrInvalidSequence,
+			"invalid account number for height zero (got %d)", acc.GetAccountNumber(),
 		)
 	}
 
@@ -258,8 +258,9 @@ func validateAccount(
 	// validate sender has enough funds
 	balance := acc.GetCoins().AmountOf(emint.DenomDefault)
 	if balance.BigInt().Cmp(ethTxMsg.Cost()) < 0 {
-		return sdk.ErrInsufficientFunds(
-			fmt.Sprintf("insufficient funds: %s < %s", balance, ethTxMsg.Cost()),
+		return sdkerrors.Wrapf(
+			sdkerrors.ErrInsufficientFunds,
+			"%s < %s%s", balance.String(), ethTxMsg.Cost().String(), emint.DenomDefault,
 		)
 	}
 
@@ -274,8 +275,9 @@ func checkNonce(
 	// current nonce).
 	seq := acc.GetSequence()
 	if ethTxMsg.Data.AccountNonce != seq {
-		return sdk.ErrInvalidSequence(
-			fmt.Sprintf("invalid nonce; got %d, expected %d", ethTxMsg.Data.AccountNonce, seq),
+		return sdkerrors.Wrapf(
+			sdkerrors.ErrInvalidSequence,
+			"got nonce %d, expected %d", ethTxMsg.Data.AccountNonce, seq,
 		)
 	}
 
@@ -302,10 +304,9 @@ func ensureSufficientMempoolFees(ctx sdk.Context, ethTxMsg *evmtypes.MsgEthereum
 	// it is assumed that the minimum fees will only include the single valid denom
 	if !ctx.MinGasPrices().IsZero() && !allGTE {
 		// reject the transaction that does not meet the minimum fee
-		return sdk.ErrInsufficientFee(
-			fmt.Sprintf(
-				"insufficient fee, got: %q required: %q", fee, ctx.MinGasPrices(),
-			),
+		return sdkerrors.Wrapf(
+			sdkerrors.ErrInsufficientFee,
+			"got: %q required: %q", fee, ctx.MinGasPrices(),
 		)
 	}