From f1bfdff6907e093ea6ce12e775f93add349adde7 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?=C3=96mer=20Faruk=20Abac=C4=B1?= Date: Wed, 8 Dec 2021 10:11:12 +0100 Subject: [PATCH] Refs #33319 -- Added comment about keys/values assertion in Query.change_aliases(). --- django/db/models/sql/query.py | 3 +++ 1 file changed, 3 insertions(+) diff --git a/django/db/models/sql/query.py b/django/db/models/sql/query.py index aaf35ee37c..fe8ac873b1 100644 --- a/django/db/models/sql/query.py +++ b/django/db/models/sql/query.py @@ -846,6 +846,9 @@ class Query(BaseExpression): relabelling any references to them in select columns and the where clause. """ + # If keys and values of change_map were to intersect, an alias might be + # updated twice (e.g. T4 -> T5, T5 -> T6, so also T4 -> T6) depending + # on their order in change_map. assert set(change_map).isdisjoint(change_map.values()) # 1. Update references in "select" (normal columns plus aliases),