fix: incorrect process loss validation for multiple finished items (b…

…ackport #37576) (#37656)

fix: incorrect process loss validation for multiple finished items (#37576)

(cherry picked from commit 92cbe58)

Co-authored-by: rohitwaghchaure <rohitw1991@gmail.com>

erpnext/stock/doctype/stock_entry/stock_entry.py

@@ -451,31 +451,37 @@ def validate_qty(self):
 								item_code.append(item.item_code)
 
 	def validate_fg_completed_qty(self):
-		item_wise_qty = {}
-		if self.purpose == "Manufacture" and self.work_order:
-			for d in self.items:
-				if d.is_finished_item:
-					if self.process_loss_qty:
-						d.qty = self.fg_completed_qty - self.process_loss_qty
+		if self.purpose != "Manufacture":
+			return
 
-					item_wise_qty.setdefault(d.item_code, []).append(d.qty)
+		fg_qty = defaultdict(float)
+		for d in self.items:
+			if d.is_finished_item:
+				fg_qty[d.item_code] += flt(d.qty)
+
+		if not fg_qty:
+			return
 
 		precision = frappe.get_precision("Stock Entry Detail", "qty")
-		for item_code, qty_list in item_wise_qty.items():
-			total = flt(sum(qty_list), precision)
+		fg_item = list(fg_qty.keys())[0]
+		fg_item_qty = flt(fg_qty[fg_item], precision)
+		fg_completed_qty = flt(self.fg_completed_qty, precision)
 
-			if (self.fg_completed_qty - total) > 0 and not self.process_loss_qty:
-				self.process_loss_qty = flt(self.fg_completed_qty - total, precision)
-				self.process_loss_percentage = flt(self.process_loss_qty * 100 / self.fg_completed_qty)
+		for d in self.items:
+			if not fg_qty.get(d.item_code):
+				continue
+
+			if (fg_completed_qty - fg_item_qty) > 0:
+				self.process_loss_qty = fg_completed_qty - fg_item_qty
 
-			if self.process_loss_qty:
-				total += flt(self.process_loss_qty, precision)
+			if not self.process_loss_qty:
+				continue
 
-			if self.fg_completed_qty != total:
+			if fg_completed_qty != (flt(fg_item_qty) + flt(self.process_loss_qty, precision)):
 				frappe.throw(
-					_("The finished product {0} quantity {1} and For Quantity {2} cannot be different").format(
-						frappe.bold(item_code), frappe.bold(total), frappe.bold(self.fg_completed_qty)
-					)
+					_(
+						"Since there is a process loss of {0} units for the finished good {1}, you should reduce the quantity by {0} units for the finished good {1} in the Items Table."
+					).format(frappe.bold(self.process_loss_qty), frappe.bold(d.item_code))
 				)
 
 	def validate_difference_account(self):