[FIX] tg_website_event_sale: не очищать корзину при выборе другого би…

…лета, если в корзине позиция с отрицательой ценой

Такое воспроизводится при выборе Upgrade / Change ticket в модуле portal_event_tickets

tg_website_event_sale/README.rst

@@ -2,7 +2,8 @@
  Online Event Ticketing customizations for Tribal Gathering
 ============================================================
 
-* Resets cart, when user registers in event in frontend
+* Resets cart, when user registers in event in frontend.
+  Does not reset cart, if there are lines with negative price units (like refund line from portal_event_ticket)
 
 * Makes event pages urls compatible for ``website_sale_affiliate`` features
 

tg_website_event_sale/controllers/main.py

@@ -10,8 +10,20 @@ class WebsiteEventSaleExtendController(WebsiteEventSaleController):
     @route()
     def registration_confirm(self, *args, **post):
         order = request.website.sale_get_order(force_create=False)
-        if order and order.state in ("draft", "cancel"):
-            order.sudo().unlink()
+        if order:
+            if order.state == "draft":
+                SaleOrderLine = request.env["sale.order.line"].sudo()
+                discount_lines = SaleOrderLine.search(
+                    [
+                        ("order_id", "=", order.id),
+                        ("price_unit", "<", 0),
+                        ("display_type", "=", False),
+                    ]
+                )
+                if not discount_lines:
+                    order.sudo().unlink()
+            elif order.state == "cancel":
+                order.sudo().unlink()
         return super().registration_confirm(*args, **post)
 
     @route()