fix(selling): reset ordered_qty when a cancelled Sales Order is unlinked from its Purchase Orders (backport #59120)

Unlinking a cancelled Sales Order from its Purchase Orders resets ordered_qty.

(cherry picked from commit ded6df3614)

erpnext/controllers/accounts_controller.py

@@ -2168,32 +2168,44 @@ class AccountsController(TransactionBase):
 				self.unlink_ref_doc_from_po()
 
 	def unlink_ref_doc_from_po(self):
-		so_items = []
-		for item in self.items:
-			so_items.append(item.name)
+		so_items = [item.name for item in self.items]
+		filters = {
+			"sales_order": self.name,
+			"sales_order_item": ["in", so_items],
+			"docstatus": ["<", 2],
+		}
 
-		linked_po = list(
-			set(
-				frappe.get_all(
-					"Purchase Order Item",
-					filters={
-						"sales_order": self.name,
-						"sales_order_item": ["in", so_items],
-						"docstatus": ["<", 2],
-					},
-					pluck="parent",
-				)
+		linked_po_items = frappe.get_all(
+			"Purchase Order Item", filters=filters, fields=["parent", "sales_order_item"]
+		)
+		if not linked_po_items:
+			return
+
+		frappe.db.set_value("Purchase Order Item", filters, {"sales_order": None, "sales_order_item": None})
+		self.update_ordered_qty_in_items({item.sales_order_item for item in linked_po_items})
+
+		linked_po = sorted({item.parent for item in linked_po_items})
+		frappe.msgprint(_("Purchase Orders {0} are un-linked").format("\n".join(linked_po)))
+
+	def update_ordered_qty_in_items(self, so_items: set[str]):
+		purchase_order_item = frappe.qb.DocType("Purchase Order Item")
+		ordered_qty = dict(
+			frappe.qb.from_(purchase_order_item)
+			.select(purchase_order_item.sales_order_item, Sum(purchase_order_item.stock_qty))
+			.where(
+				purchase_order_item.sales_order_item.isin(list(so_items))
+				& (purchase_order_item.docstatus == 1)
 			)
+			.groupby(purchase_order_item.sales_order_item)
+			.run()
 		)
 
-		if linked_po:
-			frappe.db.set_value(
-				"Purchase Order Item",
-				{"sales_order": self.name, "sales_order_item": ["in", so_items], "docstatus": ["<", 2]},
-				{"sales_order": None, "sales_order_item": None},
-			)
+		items_by_ordered_qty = defaultdict(list)
+		for so_item in so_items:
+			items_by_ordered_qty[flt(ordered_qty.get(so_item))].append(so_item)
 
-			frappe.msgprint(_("Purchase Orders {0} are un-linked").format("\n".join(linked_po)))
+		for qty, items in items_by_ordered_qty.items():
+			frappe.db.set_value("Sales Order Item", {"name": ["in", items]}, "ordered_qty", qty)
 
 	def get_tax_map(self):
 		tax_map = {}

erpnext/selling/doctype/sales_order/test_sales_order.py

@@ -1832,6 +1832,34 @@ class TestSalesOrder(AccountsTestMixin, FrappeTestCase):
 		self.assertEqual(so.packed_items[0].ordered_qty, 2)
 		self.assertEqual(so.packed_items[1].ordered_qty, 2)
 
+	def test_ordered_qty_is_reset_when_cancelled_sales_order_is_unlinked(self):
+		"""Cancelling a Sales Order unlinks its Purchase Orders, so `ordered_qty` must be recomputed."""
+		selected_items = [{"item_code": "_Test Item", "supplier": "_Test Supplier"}]
+		so = make_sales_order(item_code="_Test Item", qty=10)
+
+		purchase_order = make_purchase_order(so.name, selected_items=selected_items)
+		purchase_order.supplier = "_Test Supplier"
+		purchase_order.schedule_date = add_days(nowdate(), 1)
+		purchase_order.submit()
+
+		so.reload()
+		self.assertEqual(so.items[0].ordered_qty, 10)
+
+		so.cancel()
+		so.reload()
+		self.assertEqual(so.items[0].ordered_qty, 0)
+
+		amended_so = frappe.copy_doc(so)
+		amended_so.amended_from = so.name
+		amended_so.docstatus = 0
+		amended_so.insert()
+		amended_so.submit()
+
+		self.assertEqual(amended_so.items[0].ordered_qty, 0)
+
+		new_purchase_order = make_purchase_order(amended_so.name, selected_items=selected_items)
+		self.assertEqual(new_purchase_order.items[0].qty, 10)
+
 	def test_reserved_qty_for_closing_so(self):
 		bin = frappe.get_all(
 			"Bin",