evm: update empty hash check for storage state (#1016)

x/evm/types/storage.go

@@ -2,11 +2,10 @@ package types
 
 import (
 	"fmt"
+	"strings"
 
 	sdkerrors "github.com/cosmos/cosmos-sdk/types/errors"
 	"github.com/ethereum/go-ethereum/common"
-
-	"github.com/tharsis/ethermint/types"
 )
 
 // Storage represents the account Storage map as a slice of single key value
@@ -49,11 +48,12 @@ func (s Storage) Copy() Storage {
 }
 
 // Validate performs a basic validation of the State fields.
+// NOTE: state value can be empty
 func (s State) Validate() error {
-	if types.IsEmptyHash(s.Key) {
-		return sdkerrors.Wrap(ErrInvalidState, "state key hash cannot be empty")
+	if strings.TrimSpace(s.Key) == "" {
+		return sdkerrors.Wrap(ErrInvalidState, "state key hash cannot be blank")
 	}
-	// NOTE: state value can be empty
+
 	return nil
 }
 

x/evm/types/storage_test.go

@@ -23,7 +23,7 @@ func TestStorageValidate(t *testing.T) {
 		{
 			"empty storage key bytes",
 			Storage{
-				{Key: common.Hash{}.String()},
+				{Key: ""},
 			},
 			false,
 		},