Fixed #35716 -- Fixed VariableDoesNotExist when rendering admin fieldsets.

Regression in 01ed59f.

Thank you to Fábio Domingues and Marijke Luttekes for the report,
and thank you to Natalia Bidart for the review.

Author: sarahboyce

django/contrib/admin/templates/admin/change_form.html

@@ -47,7 +47,7 @@
 
 {% block field_sets %}
 {% for fieldset in adminform %}
-  {% include "admin/includes/fieldset.html" with heading_level=2 id_suffix=forloop.counter0 %}
+  {% include "admin/includes/fieldset.html" with heading_level=2 prefix="fieldset" id_prefix=0 id_suffix=forloop.counter0 %}
 {% endfor %}
 {% endblock %}
 

django/contrib/admin/templates/admin/edit_inline/stacked.html

@@ -26,7 +26,7 @@ <h3><b>{{ inline_admin_formset.opts.verbose_name|capfirst }}:</b> <span class="i
 
   {% with parent_counter=forloop.counter0 %}
     {% for fieldset in inline_admin_form %}
-      {% include "admin/includes/fieldset.html" with heading_level=4 id_prefix=parent_counter id_suffix=forloop.counter0 %}
+      {% include "admin/includes/fieldset.html" with heading_level=4 prefix=fieldset.formset.prefix id_prefix=parent_counter id_suffix=forloop.counter0 %}
     {% endfor %}
   {% endwith %}
 

django/contrib/admin/templates/admin/includes/fieldset.html

@@ -1,4 +1,4 @@
-{% with prefix=fieldset.formset.prefix|default:"fieldset" id_prefix=id_prefix|default:"0" id_suffix=id_suffix|default:"0" name=fieldset.name|default:""|slugify %}
+{% with name=fieldset.name|default:""|slugify %}
 <fieldset class="module aligned {{ fieldset.classes }}"{% if name %} aria-labelledby="{{ prefix }}-{{ id_prefix}}-{{ name }}-{{ id_suffix }}-heading"{% endif %}>
     {% if name %}
         {% if fieldset.is_collapsible %}<details><summary>{% endif %}

docs/releases/5.1.1.txt

@@ -35,3 +35,6 @@ Bugfixes
 * Restored, following a regression in Django 5.1, the ability to override the
   timezone and role setting behavior used within the ``init_connection_state``
   method of the PostgreSQL backend (:ticket:`35688`).
+
+* Fixed a bug in Django 5.1 where variable lookup errors were logged when
+  rendering admin fieldsets (:ticket:`35716`).

tests/admin_inlines/tests.py

@@ -1768,6 +1768,13 @@ class TestInlineWithFieldsets(TestDataMixin, TestCase):
     def setUp(self):
         self.client.force_login(self.superuser)
 
+    @override_settings(DEBUG=True)
+    def test_fieldset_context_fully_set(self):
+        url = reverse("admin:admin_inlines_photographer_add")
+        with self.assertRaisesMessage(AssertionError, "no logs"):
+            with self.assertLogs("django.template", "DEBUG"):
+                self.client.get(url)
+
     def test_inline_headings(self):
         response = self.client.get(reverse("admin:admin_inlines_photographer_add"))
         # Page main title.