[fix] Invoice/Delivery note customer po_no overwritten by Sales order null po_no (#15785)
diff --git a/erpnext/controllers/selling_controller.py b/erpnext/controllers/selling_controller.py
index 57c6556..719f4c7 100644
--- a/erpnext/controllers/selling_controller.py
+++ b/erpnext/controllers/selling_controller.py
@@ -345,7 +345,8 @@
sales_orders = list(set([d.get(ref_fieldname) for d in self.items if d.get(ref_fieldname)]))
if sales_orders:
po_nos = frappe.get_all('Sales Order', 'po_no', filters = {'name': ('in', sales_orders)})
- self.po_no = ', '.join(list(set([d.po_no for d in po_nos if d.po_no])))
+ if po_nos and po_nos[0].get('po_no'):
+ self.po_no = ', '.join(list(set([d.po_no for d in po_nos if d.po_no])))
def validate_items(self):
# validate items to see if they have is_sales_item enabled