update cart

pkg/promotions/types.go

@@ -400,6 +400,14 @@ func (sf *StateFile) GetPromotion(id string) (*PromotionRule, bool) {
 func LoadStateFile(fileName string) (*StateFile, error) {
 	f, err := os.Open(fileName)
 	if err != nil {
+		if os.IsNotExist(err) {
+			return &StateFile{
+				State: PromotionState{
+					Promotions: []PromotionRule{},
+				},
+				Version: 1,
+			}, nil
+		}
 		return nil, err
 	}
 	defer f.Close()