fix: budget naming series (backport #48075) (#48080)

* fix: budget naming series (#48075)

(cherry picked from commit c4bdf2a721)

# Conflicts:
#	erpnext/accounts/doctype/budget/budget.json

* chore: resolve conflict

---------

Co-authored-by: Diptanil Saha <diptanil@frappe.io>

erpnext/accounts/doctype/budget/budget.json

@@ -7,10 +7,10 @@
  "editable_grid": 1,
  "engine": "InnoDB",
  "field_order": [
+  "naming_series",
   "budget_against",
   "company",
   "cost_center",
-  "naming_series",
   "project",
   "fiscal_year",
   "column_break_3",
@@ -195,19 +195,19 @@
   },
   {
    "fieldname": "naming_series",
-   "fieldtype": "Data",
-   "hidden": 1,
+   "fieldtype": "Select",
    "label": "Series",
    "no_copy": 1,
+   "options": "BUDGET-.YYYY.-",
    "print_hide": 1,
-   "read_only": 1,
+   "reqd": 1,
    "set_only_once": 1
   }
  ],
  "index_web_pages_for_search": 1,
  "is_submittable": 1,
  "links": [],
- "modified": "2022-10-10 22:14:36.361509",
+ "modified": "2025-06-16 15:57:13.114981",
  "modified_by": "Administrator",
  "module": "Accounts",
  "name": "Budget",
@@ -235,4 +235,4 @@
  "sort_order": "DESC",
  "states": [],
  "track_changes": 1
-}
+}

erpnext/accounts/doctype/budget/budget.py

@@ -48,7 +48,7 @@ class Budget(Document):
 		cost_center: DF.Link | None
 		fiscal_year: DF.Link
 		monthly_distribution: DF.Link | None
-		naming_series: DF.Data | None
+		naming_series: DF.Literal["BUDGET-.YYYY.-"]
 		project: DF.Link | None
 	# end: auto-generated types
 
@@ -136,9 +136,6 @@ class Budget(Document):
 		):
 			self.applicable_on_booking_actual_expenses = 1
 
-	def before_naming(self):
-		self.naming_series = f"{{{frappe.scrub(self.budget_against)}}}./.{self.fiscal_year}/.###"
-
 
 def validate_expense_against_budget(args, expense_amount=0):
 	args = frappe._dict(args)