fix: block disabled/frozen suppliers on Request for Quotation

Request for Quotation overrides validate() entirely and never calls
super().validate(), so it never goes through AccountsController's
party validation. Suppliers also sit in a child table, so the shared
PartyValidator wouldn't have caught it anyway (it only checks a single
top-level party field). A disabled or frozen Supplier could be added
to an RFQ and the RFQ submitted without any warning.

Also filters the suppliers grid's supplier Link field to disabled=0,
matching the same client-side fix applied to Opportunity's party_name.

erpnext/buying/doctype/request_for_quotation/request_for_quotation.js

@@ -22,6 +22,10 @@ frappe.ui.form.on("Request for Quotation", {
 			};
 		};
 
+		frm.set_query("supplier", "suppliers", function () {
+			return { filters: { disabled: 0 } };
+		});
+
 		frm.set_query("warehouse", "items", () => ({
 			filters: {
 				company: frm.doc.company,

erpnext/buying/doctype/request_for_quotation/request_for_quotation.py

@@ -13,6 +13,7 @@ from frappe.utils import get_url
 from frappe.utils.print_format import download_pdf
 from frappe.utils.user import get_user_fullname
 
+from erpnext.accounts.party import validate_party_frozen_disabled
 from erpnext.buying.utils import validate_for_items
 from erpnext.controllers.buying_controller import BuyingController
 
@@ -122,6 +123,8 @@ class RequestforQuotation(BuyingController):
 
 	def validate_supplier_list(self):
 		for d in self.suppliers:
+			validate_party_frozen_disabled(self.company, "Supplier", d.supplier)
+
 			prevent_rfqs = frappe.db.get_value("Supplier", d.supplier, "prevent_rfqs")
 			if prevent_rfqs:
 				standing = frappe.db.get_value("Supplier Scorecard", d.supplier, "status")

erpnext/buying/doctype/request_for_quotation/test_request_for_quotation.py

@@ -18,6 +18,7 @@ from erpnext.buying.doctype.request_for_quotation.request_for_quotation import (
 from erpnext.controllers.accounts_controller import InvalidQtyError
 from erpnext.crm.doctype.opportunity.mapper import make_request_for_quotation as make_rfq
 from erpnext.crm.doctype.opportunity.test_opportunity import make_opportunity
+from erpnext.exceptions import PartyDisabled
 from erpnext.stock.doctype.item.test_item import make_item
 from erpnext.stock.doctype.material_request.test_material_request import make_material_request
 from erpnext.templates.pages.rfq import check_supplier_has_docname_access
@@ -89,6 +90,17 @@ class TestRequestforQuotation(ERPNextTestSuite):
 		)
 		self.assertRaises(frappe.ValidationError, rfq.save)
 
+	def test_rfq_blocked_for_disabled_supplier(self):
+		frappe.db.set_value("Supplier", "_Test Supplier", "disabled", 1)
+		rfq = make_request_for_quotation(
+			supplier_data=[{"supplier": "_Test Supplier", "supplier_name": "_Test Supplier"}],
+			do_not_save=True,
+		)
+		self.assertRaises(PartyDisabled, rfq.save)
+
+		frappe.db.set_value("Supplier", "_Test Supplier", "disabled", 0)
+		rfq.save()
+
 	def test_rfq_status_lifecycle(self):
 		rfq = make_request_for_quotation()
 		self.assertEqual(rfq.status, "Submitted")