From 90c716bce0de7710f7f63d6ea42ff01df10f4061 Mon Sep 17 00:00:00 2001
From: Gavin D'souza <gavin18d@gmail.com>
Date: Fri, 17 Jun 2022 12:10:43 +0530
Subject: [PATCH] fix(sequence): Setup & use SequenceGeneratorLimitExceeded
 error

---
 frappe/database/mariadb/database.py  |  4 ++++
 frappe/database/postgres/database.py |  3 ++-
 frappe/database/sequence.py          | 17 +++++++++++------
 frappe/tests/test_sequence.py        |  6 +-----
 4 files changed, 18 insertions(+), 12 deletions(-)

diff --git a/frappe/database/mariadb/database.py b/frappe/database/mariadb/database.py
index da33007d5d..327c995d48 100644
--- a/frappe/database/mariadb/database.py
+++ b/frappe/database/mariadb/database.py
@@ -46,6 +46,10 @@ class MariaDBExceptionUtil:
 	SQLError = mariadb.ProgrammingError
 	DataError = mariadb.DataError
 
+	# match ER_SEQUENCE_RUN_OUT - https://mariadb.com/kb/en/mariadb-error-codes/
+	SequenceGeneratorLimitExceeded = mariadb.ProgrammingError
+	SequenceGeneratorLimitExceeded.errno = 4084
+
 	@staticmethod
 	def is_deadlocked(e: mariadb.Error) -> bool:
 		return getattr(e, "errno", None) == ER.LOCK_DEADLOCK
diff --git a/frappe/database/postgres/database.py b/frappe/database/postgres/database.py
index 2444d41279..f5ecabd6c4 100644
--- a/frappe/database/postgres/database.py
+++ b/frappe/database/postgres/database.py
@@ -13,7 +13,7 @@ from psycopg2.errorcodes import (
 	UNDEFINED_TABLE,
 	UNIQUE_VIOLATION,
 )
-from psycopg2.errors import SyntaxError
+from psycopg2.errors import SequenceGeneratorLimitExceeded, SyntaxError
 from psycopg2.extensions import ISOLATION_LEVEL_REPEATABLE_READ
 
 import frappe
@@ -44,6 +44,7 @@ class PostgresExceptionUtil:
 	SQLError = psycopg2.ProgrammingError
 	DataError = psycopg2.DataError
 	InterfaceError = psycopg2.InterfaceError
+	SequenceGeneratorLimitExceeded = SequenceGeneratorLimitExceeded
 
 	@staticmethod
 	def is_deadlocked(e):
diff --git a/frappe/database/sequence.py b/frappe/database/sequence.py
index 6a352d20d1..54362a5895 100644
--- a/frappe/database/sequence.py
+++ b/frappe/database/sequence.py
@@ -57,12 +57,17 @@ def create_sequence(
 
 
 def get_next_val(doctype_name: str, slug: str = "_id_seq") -> int:
-	return db.multisql(
-		{
-			"postgres": f"select nextval('\"{scrub(doctype_name + slug)}\"')",
-			"mariadb": f"select nextval(`{scrub(doctype_name + slug)}`)",
-		}
-	)[0][0]
+	sequence_name = scrub(f"{doctype_name}{slug}")
+
+	if db.db_type == "postgres":
+		sequence_name = f"'\"{sequence_name}\"'"
+	elif db.db_type == "mariadb":
+		sequence_name = f"`{sequence_name}`"
+
+	try:
+		return db.sql(f"SELECT nextval({sequence_name})")[0][0]
+	except IndexError:
+		raise db.SequenceGeneratorLimitExceeded
 
 
 def set_next_val(
diff --git a/frappe/tests/test_sequence.py b/frappe/tests/test_sequence.py
index 82bb8ab257..c6ea0bc8c0 100644
--- a/frappe/tests/test_sequence.py
+++ b/frappe/tests/test_sequence.py
@@ -1,5 +1,3 @@
-import psycopg2
-
 import frappe
 from frappe.tests.utils import FrappeTestCase
 
@@ -34,10 +32,8 @@ class TestSequence(FrappeTestCase):
 
 		try:
 			frappe.db.get_next_sequence_val(seq_name)
-		except psycopg2.errors.SequenceGeneratorLimitExceeded:
+		except frappe.db.SequenceGeneratorLimitExceeded:
 			pass
-		except frappe.db.ProgrammingError as e:
-			self.assertEqual(getattr(e, "errno", None), 4084)
 		else:
 			self.fail("NEXTVAL didn't raise any error upon sequence's end")