Merge branch 'develop' of https://github.com/frappe/erpnext into develop
diff --git a/erpnext/accounts/doctype/pricing_rule/pricing_rule.py b/erpnext/accounts/doctype/pricing_rule/pricing_rule.py
index 430dce7..e871d98 100644
--- a/erpnext/accounts/doctype/pricing_rule/pricing_rule.py
+++ b/erpnext/accounts/doctype/pricing_rule/pricing_rule.py
@@ -34,8 +34,7 @@
 
 	def validate_duplicate_apply_on(self):
 		field = apply_on_dict.get(self.apply_on)
-		values = [d.get(frappe.scrub(self.apply_on)) for d in self.get(field)]
-
+		values = [d.get(frappe.scrub(self.apply_on)) for d in self.get(field) if field]
 		if len(values) != len(set(values)):
 			frappe.throw(_("Duplicate {0} found in the table").format(self.apply_on))