[IMP] Apply suggested changes from FrankC013 to put price_extra to 0.0

product_variant_sale_price/models/product_product.py

@@ -27,10 +27,39 @@ def write(self, vals):
             template._update_fix_price(vals)
         return res
 
+    def _get_combination_info(
+        self,
+        combination=False,
+        product_id=False,
+        add_qty=1,
+        pricelist=False,
+        parent_combination=False,
+        only_template=False,
+    ):
+        res = super()._get_combination_info(
+            combination,
+            product_id,
+            add_qty,
+            pricelist,
+            parent_combination,
+            only_template,
+        )
+        res["price_extra"] = 0.0
+        return res
+
 
 class ProductProduct(models.Model):
     _inherit = "product.product"
 
+    lst_price = fields.Float(
+        compute="_compute_lst_price",
+        inverse="_inverse_product_lst_price",
+    )
+    list_price = fields.Float(
+        compute="_compute_list_price",
+    )
+    fix_price = fields.Float()
+
     @api.depends("fix_price")
     def _compute_lst_price(self):
         uom_model = self.env["uom.uom"]
@@ -71,11 +100,9 @@ def _inverse_product_lst_price(self):
                 ).list_price = min(fix_prices)
             product.write(vals)
 
-    lst_price = fields.Float(
-        compute="_compute_lst_price",
-        inverse="_inverse_product_lst_price",
-    )
-    list_price = fields.Float(
-        compute="_compute_list_price",
-    )
-    fix_price = fields.Float()
+    def _compute_product_price_extra(self):
+        """the sale.order.line module calculates the price_unit by adding
+        the value of price_extra and this can generate inconsistencies
+        if the field has old data stored."""
+        for product in self:
+            product.price_extra = 0.0