Merge pull request #57647 from aerele/fix/sales-zero-qty-return-validation

fix(sales): reject sales returns where every item has zero quantity

erpnext/controllers/sales_and_purchase_return.py

@@ -160,7 +160,14 @@ def validate_returned_items(doc):
 				):
 					frappe.throw(_("Warehouse is mandatory"))
 
-			if doc.doctype in ("Purchase Invoice", "Purchase Receipt", "Subcontracting Receipt"):
+			if doc.doctype in (
+				"Purchase Invoice",
+				"Purchase Receipt",
+				"Subcontracting Receipt",
+				"Sales Invoice",
+				"Delivery Note",
+				"POS Invoice",
+			):
 				if flt(d.qty) < 0 or flt(d.get("received_qty")) < 0:
 					items_returned = True
 			else:

erpnext/controllers/tests/test_sales_and_purchase_return.py

@@ -78,3 +78,35 @@ class TestSalesAndPurchaseReturn(ERPNextTestSuite):
 		return_pi.items[0].item_code = ""
 
 		self.assertRaises(frappe.ValidationError, return_pi.save)
+
+	def test_delivery_note_zero_qty_return_is_rejected(self):
+		# A return with every item at qty 0 moves no stock and no value, so it must be
+		# rejected the same way a return with no items at all would be.
+		from erpnext.stock.doctype.delivery_note.mapper import make_sales_return
+		from erpnext.stock.doctype.delivery_note.test_delivery_note import create_delivery_note
+		from erpnext.stock.doctype.stock_entry.stock_entry_utils import make_stock_entry
+
+		se = make_stock_entry(item_code="_Test Item", target="_Test Warehouse - _TC", qty=20, basic_rate=100)
+		self.addCleanup(self._cancel_and_delete, "Stock Entry", se.name)
+
+		dn = create_delivery_note(qty=5)
+		self.addCleanup(self._cancel_and_delete, "Delivery Note", dn.name)
+
+		return_dn = make_sales_return(dn.name)
+		return_dn.items[0].qty = 0
+
+		self.assertRaises(frappe.ValidationError, return_dn.insert)
+
+	def test_sales_invoice_zero_qty_return_is_rejected(self):
+		# Same rule for a standalone (non stock-affecting) Sales Invoice return: qty 0 on
+		# every row must be rejected, not silently accepted as a no-op credit note.
+		from erpnext.accounts.doctype.sales_invoice.test_sales_invoice import create_sales_invoice
+		from erpnext.controllers.sales_and_purchase_return import make_return_doc
+
+		si = create_sales_invoice(qty=10)
+		self.addCleanup(self._cancel_and_delete, "Sales Invoice", si.name)
+
+		return_si = make_return_doc(si.doctype, si.name)
+		return_si.items[0].qty = 0
+
+		self.assertRaises(frappe.ValidationError, return_si.save)