From 192fd21634e4f976612837d52d99cf4255b5a8cf Mon Sep 17 00:00:00 2001
From: Ankush Menat <ankush@frappe.io>
Date: Mon, 15 Dec 2025 12:21:26 +0530
Subject: [PATCH] fix: Remove old option from UI

It will continue to work in DB and logic by setting `format:` prefix.
---
 frappe/core/doctype/doctype/doctype.py   | 1 +
 frappe/public/js/frappe/doctype/index.js | 7 +++++++
 2 files changed, 8 insertions(+)

diff --git a/frappe/core/doctype/doctype/doctype.py b/frappe/core/doctype/doctype/doctype.py
index bad1bf9ae6..9323d7c69f 100644
--- a/frappe/core/doctype/doctype/doctype.py
+++ b/frappe/core/doctype/doctype/doctype.py
@@ -455,6 +455,7 @@ class DocType(Document):
 		# We swapped naming_rule field old/new to discourage use of "format:"
 		if self.autoname and self.autoname.startswith("format:"):
 			self.naming_rule = "Expression (old style)"
+			frappe.toast(_("Warning: Usage of 'format:' is discouraged."), indicator="yellow")
 
 		if self.naming_rule == "Expression (old style)" and not self.autoname.startswith("format:"):
 			self.naming_rule = "Expression"
diff --git a/frappe/public/js/frappe/doctype/index.js b/frappe/public/js/frappe/doctype/index.js
index 2502fadb5b..f06ab54876 100644
--- a/frappe/public/js/frappe/doctype/index.js
+++ b/frappe/public/js/frappe/doctype/index.js
@@ -24,6 +24,7 @@ frappe.model.DocTypeController = class DocTypeController extends frappe.ui.form.
 
 	refresh() {
 		this.show_db_utilization();
+		this.remove_old_style_naming_option();
 	}
 
 	show_db_utilization() {
@@ -45,6 +46,12 @@ frappe.model.DocTypeController = class DocTypeController extends frappe.ui.form.
 			});
 	}
 
+	remove_old_style_naming_option() {
+		let df = this.frm.get_docfield("naming_rule");
+		df.options = df.options.replace("Expression (old style)\n", "");
+		this.frm.refresh_field("naming_rule");
+	}
+
 	max_attachments() {
 		if (!this.frm.doc.max_attachments) {
 			return;