error migration (#254)

* migrate errors

* ante handler errors

* return err instead of panic

types/errors.go

@@ -1,60 +1,21 @@
 package types
 
 import (
-	sdk "github.com/cosmos/cosmos-sdk/types"
+	sdkerrors "github.com/cosmos/cosmos-sdk/types/errors"
 )
 
-// Ethermint error codes
 const (
-	// DefaultCodespace reserves a Codespace for Ethermint.
-	DefaultCodespace sdk.CodespaceType = "ethermint"
-
-	CodeInvalidValue   sdk.CodeType = 1
-	CodeInvalidChainID sdk.CodeType = 2
-	CodeInvalidSender  sdk.CodeType = 3
-	CodeVMExecution    sdk.CodeType = 4
-	CodeInvalidNonce   sdk.CodeType = 5
+	// RootCodespace is the codespace for all errors defined in this package
+	RootCodespace = "ethermint"
 )
 
-// CodeToDefaultMsg takes the CodeType variable and returns the error string
-func CodeToDefaultMsg(code sdk.CodeType) string {
-	switch code {
-	case CodeInvalidValue:
-		return "invalid value"
-	case CodeInvalidChainID:
-		return "invalid chain ID"
-	case CodeInvalidSender:
-		return "could not derive sender from transaction"
-	case CodeVMExecution:
-		return "error while executing evm transaction"
-	case CodeInvalidNonce:
-		return "invalid nonce"
-	default:
-		return sdk.CodeToDefaultMsg(code)
-	}
-}
+var (
+	// ErrInvalidValue returns an error resulting from an invalid value.
+	ErrInvalidValue = sdkerrors.Register(RootCodespace, 1, "invalid value")
 
-// ErrInvalidValue returns a standardized SDK error resulting from an invalid value.
-func ErrInvalidValue(msg string) sdk.Error {
-	return sdk.NewError(DefaultCodespace, CodeInvalidValue, msg)
-}
+	// ErrInvalidChainID returns an error resulting from an invalid chain ID.
+	ErrInvalidChainID = sdkerrors.Register(RootCodespace, 2, "invalid chain ID")
 
-// ErrInvalidChainID returns a standardized SDK error resulting from an invalid chain ID.
-func ErrInvalidChainID(msg string) sdk.Error {
-	return sdk.NewError(DefaultCodespace, CodeInvalidChainID, msg)
-}
-
-// ErrInvalidSender returns a standardized SDK error resulting from an invalid transaction sender.
-func ErrInvalidSender(msg string) sdk.Error {
-	return sdk.NewError(DefaultCodespace, CodeInvalidSender, msg)
-}
-
-// ErrVMExecution returns a standardized SDK error resulting from an error in EVM execution.
-func ErrVMExecution(msg string) sdk.Error {
-	return sdk.NewError(DefaultCodespace, CodeVMExecution, msg)
-}
-
-// ErrVMExecution returns a standardized SDK error resulting from an error in EVM execution.
-func ErrInvalidNonce(msg string) sdk.Error {
-	return sdk.NewError(DefaultCodespace, CodeInvalidNonce, msg)
-}
+	// ErrVMExecution returns an error resulting from an error in EVM execution.
+	ErrVMExecution = sdkerrors.Register(RootCodespace, 3, "error while executing evm transaction")
+)