[Fix] Don't allow user to change the select fieldtype to data from the customize form

frappe/__init__.py

@@ -943,6 +943,7 @@ def make_property_setter(args, ignore_validate=False, validate_fields_for_doctyp
 		})
 		ps.flags.ignore_validate = ignore_validate
 		ps.flags.validate_fields_for_doctype = validate_fields_for_doctype
+		ps.validate_fieldtype_change()
 		ps.insert()
 
 def import_doc(path, ignore_links=False, ignore_insert=False, insert=False):

frappe/custom/doctype/property_setter/property_setter.py

@@ -3,9 +3,12 @@
 
 from __future__ import unicode_literals
 import frappe
+from frappe import _
 
 from frappe.model.document import Document
 
+not_allowed_fieldtype_change = ['naming_series']
+
 class PropertySetter(Document):
 	def autoname(self):
 		self.name = self.doc_type + "-" \
@@ -13,6 +16,18 @@ class PropertySetter(Document):
 			+ self.property
 
 	def validate(self):
+		self.validate_fieldtype_change()
+		self.delete_property_setter()
+
+		# clear cache
+		frappe.clear_cache(doctype = self.doc_type)
+
+	def validate_fieldtype_change(self):
+		if self.field_name in not_allowed_fieldtype_change and \
+			self.property == 'fieldtype':
+			frappe.throw(_("Field type cannot be changed for {0}").format(self.field_name))
+
+	def delete_property_setter(self):
 		"""delete other property setters on this, if this is new"""
 		if self.get('__islocal'):
 			frappe.db.sql("""delete from `tabProperty Setter` where
@@ -21,9 +36,6 @@ class PropertySetter(Document):
 				and ifnull(field_name,'') = ifnull(%(field_name)s, '')
 				and property = %(property)s""", self.get_valid_dict())
 
-		# clear cache
-		frappe.clear_cache(doctype = self.doc_type)
-
 	def get_property_list(self, dt):
 		return frappe.db.sql("""select fieldname, label, fieldtype
 		from tabDocField