fix(stock): recalculate billing status of returned delivery notes (backport #58953) (#58986)

Co-authored-by: Raffael Meyer <14891507+barredterra@users.noreply.github.com>

erpnext/patches.txt

@@ -449,4 +449,5 @@ erpnext.patches.v16_0.backfill_repost_accounting_ledger_status
 erpnext.patches.v16_0.merge_seeded_item_group_root
 erpnext.patches.v16_0.remove_frappe_crm_custom_fields
 erpnext.patches.v16_0.append_fieldname_to_pos_search_fields
-erpnext.patches.v16_0.add_transaction_roles_to_sms_settings
+erpnext.patches.v16_0.add_transaction_roles_to_sms_settings
+erpnext.patches.v16_0.recalculate_returned_delivery_note_billing_status

erpnext/patches/v16_0/recalculate_returned_delivery_note_billing_status.py

@@ -0,0 +1,32 @@
+import frappe
+
+
+def execute():
+	"""Recalculate billing status of Delivery Notes left open by a return.
+
+	Returning the uninvoiced qty of a Delivery Note did not recalculate the original
+	Delivery Note, so it stayed "To Bill" / "Partially Billed" with nothing left to invoice.
+	"""
+	dn = frappe.qb.DocType("Delivery Note")
+	dn_item = frappe.qb.DocType("Delivery Note Item")
+
+	delivery_notes = (
+		frappe.qb.from_(dn)
+		.inner_join(dn_item)
+		.on(dn_item.parent == dn.name)
+		.select(dn.name)
+		.distinct()
+		.where(
+			(dn.docstatus == 1)
+			& (dn.is_return == 0)
+			& dn.status.isin(["To Bill", "Partially Billed"])
+			& (dn_item.returned_qty > 0)
+		)
+		.run(pluck=True)
+	)
+
+	for name in delivery_notes:
+		doc = frappe.get_doc("Delivery Note", name)
+		doc.update_billing_percentage(update_modified=False)
+		doc.load_from_db()
+		doc.set_status(update=True, update_modified=False)

erpnext/stock/doctype/delivery_note/test_delivery_note.py

@@ -1099,6 +1099,67 @@ class TestDeliveryNote(FrappeTestCase):
 		self.assertEqual(dn.per_billed, 50)
 		self.assertEqual(dn.status, "Partially Billed")
 
+	def test_billing_status_repair_patch(self):
+		"""Returns submitted before #58869 left the original Delivery Note's per_billed stale.
+
+		The repair patch recalculates such notes: a directly invoiced one whose remaining
+		qty was returned becomes Completed, an uninvoiced Sales Order linked one goes back
+		to To Bill.
+		"""
+		from erpnext.patches.v16_0 import recalculate_returned_delivery_note_billing_status as patch
+		from erpnext.stock.doctype.delivery_note.delivery_note import make_sales_return
+
+		# Delivery Note invoiced for 2 of 5 qty, the remaining 3 returned -> fully billed
+		make_stock_entry(target="_Test Warehouse - _TC", qty=5, basic_rate=100)
+		dn = create_delivery_note(qty=5)
+
+		si = make_sales_invoice(dn.name)
+		si.items[0].qty = 2
+		si.insert()
+		si.submit()
+
+		dn_return = make_sales_return(dn.name)
+		dn_return.items[0].qty = -3
+		dn_return.insert()
+		# Mimic the submit request, which reconstructs the document from client data.
+		frappe.get_doc(dn_return.as_dict()).submit()
+
+		dn.load_from_db()
+		self.assertEqual(dn.items[0].returned_qty, 3)
+		self.assertEqual(dn.per_billed, 100)
+
+		# Sales Order linked Delivery Note, nothing invoiced, partly returned -> unbilled
+		so = make_sales_order(qty=10)
+		so_dn = create_dn_against_so(so.name, delivered_qty=5)
+
+		so_dn_return = make_sales_return(so_dn.name)
+		so_dn_return.items[0].qty = -2
+		so_dn_return.insert()
+		frappe.get_doc(so_dn_return.as_dict()).submit()
+
+		so_dn.load_from_db()
+		self.assertEqual(so_dn.items[0].returned_qty, 2)
+		self.assertEqual(so_dn.per_billed, 0)
+
+		# Mimic the state left behind by a return submitted before the fix
+		for name, per_billed in ((dn.name, 40), (so_dn.name, 50)):
+			frappe.db.set_value(
+				"Delivery Note",
+				name,
+				{"per_billed": per_billed, "status": "Partially Billed"},
+				update_modified=False,
+			)
+
+		patch.execute()
+
+		dn.load_from_db()
+		self.assertEqual(dn.per_billed, 100)
+		self.assertEqual(dn.status, "Completed")
+
+		so_dn.load_from_db()
+		self.assertEqual(so_dn.per_billed, 0)
+		self.assertEqual(so_dn.status, "To Bill")
+
 	def test_dn_billing_status_case2(self):
 		# SO -> SI and SO -> DN1, DN2
 		from erpnext.selling.doctype.sales_order.sales_order import (