Test another case

core/encoding.go

@@ -17,6 +17,7 @@ import (
 	"github.com/sourcenetwork/immutable"
 
 	"github.com/sourcenetwork/defradb/client"
+	"github.com/sourcenetwork/defradb/client/request"
 	"github.com/sourcenetwork/defradb/encoding"
 )
 
@@ -274,7 +275,9 @@ func normalizeIndexDataStoreKeyValues(key *IndexDataStoreKey, fields []client.Fi
 		var val any
 		if i == len(key.fields)-1 && len(key.fields)-len(fields) == 1 {
 			bytes, ok := key.fields[i].Value.([]byte)
-			ok = ok
+			if !ok {
+				return client.NewErrUnexpectedType[[]byte](request.DocIDArgName, key.fields[i].Value)
+			}
 			val = string(bytes)
 		} else {
 			val, err = NormalizeFieldValue(fields[i], key.fields[i].Value)

core/key_test.go

@@ -393,6 +393,11 @@ func TestDecodeIndexDataStoreKey_InvalidKey(t *testing.T) {
 			val:       encodeKey(colID, indexID, 5, false, 7, false, 9, false),
 			numFields: 2,
 		},
+		{
+			name:      "invalid docID value",
+			val:       encoding.EncodeUvarintAscending(append(encodeKey(colID, indexID, 5, false), '/'), 5),
+			numFields: 1,
+		},
 	}
 	indexDesc := client.IndexDescription{ID: indexID, Fields: []client.IndexedFieldDescription{{}}}
 	for _, c := range cases {