[pull] main from django:main

django/contrib/admin/templatetags/admin_list.py

@@ -228,7 +228,7 @@ def link_in_col(is_first, field_name, cl):
             empty_value_display = getattr(
                 attr, "empty_value_display", empty_value_display
             )
-            # Find boolean fields on relations.
+            # Find a terminal field from a chain of relations.
             if f is None and isinstance(field_name, str) and LOOKUP_SEP in field_name:
                 try:
                     f = get_fields_from_path(cl.model, field_name)[-1]
@@ -246,11 +246,10 @@ def link_in_col(is_first, field_name, cl):
                     row_classes.append("nowrap")
             else:
                 if isinstance(f.remote_field, models.ManyToOneRel):
-                    field_val = getattr(result, f.name)
-                    if field_val is None:
+                    if value is None:
                         result_repr = empty_value_display
                     else:
-                        result_repr = field_val
+                        result_repr = value
                 else:
                     result_repr = display_for_field(
                         value,

docs/releases/6.1.1.txt

@@ -12,3 +12,7 @@ Bugfixes
 * Fixed a regression in Django 6.1 where the deprecation of double-dot variable
   lookups incorrectly applied to string and translated template literals
   containing two consecutive dots, such as ``{{ "a..b" }}`` (:ticket:`37257`).
+
+* Fixed a regression in Django 6.1 where :attr:`.ModelAdmin.list_display`
+  entries that traverse multiple relations using ``__`` could crash or display
+  incorrect values (:ticket:`37270`).

tests/admin_changelist/models.py

@@ -23,6 +23,7 @@ class Child(models.Model):
 class GrandChild(models.Model):
     parent = models.ForeignKey(Child, models.SET_NULL, editable=False, null=True)
     name = models.CharField(max_length=30, blank=True)
+    sibling = models.ForeignKey("self", models.SET_NULL, editable=False, null=True)
 
     def __str__(self):
         return self.name
@@ -46,6 +47,7 @@ class Band(models.Model):
 class Musician(models.Model):
     name = models.CharField(max_length=30)
     age = models.IntegerField(null=True, blank=True)
+    genre = models.ForeignKey(Genre, null=True, on_delete=models.SET_NULL)
 
     def __str__(self):
         return self.name

tests/admin_changelist/tests.py

@@ -1793,6 +1793,53 @@ class ChildAdmin(admin.ModelAdmin):
         cl = m.get_changelist_instance(request)
         self.assertEqual(cl.get_ordering_field_columns(), {2: "asc"})
 
+    def test_list_display_first_degree_relation(self):
+        parent = Parent.objects.create(name="I am your parent")
+        child = Child.objects.create(name="I am your child", parent=parent)
+        grand = GrandChild.objects.create(name="I am your grandchild", parent=child)
+        GrandChild.objects.create(name="has sibling", parent=child, sibling=grand)
+
+        class GrandChildAdmin(admin.ModelAdmin):
+            list_display = ["name", "sibling"]
+
+        m = GrandChildAdmin(GrandChild, custom_site)
+        request = self._mocked_authenticated_request("/grandchild/", self.superuser)
+        response = m.changelist_view(request)
+        self.assertContains(response, '<h2 class="main">I am your grandchild')
+
+    def test_list_display_second_degree_relation(self):
+        parent = Parent.objects.create(name="I am your parent")
+        child = Child.objects.create(name="I am your child", parent=parent)
+        GrandChild.objects.create(name="I am your grandchild", parent=child)
+
+        class GrandChildAdmin(admin.ModelAdmin):
+            list_display = ["name", "parent__parent"]
+
+        m = GrandChildAdmin(GrandChild, custom_site)
+        request = self._mocked_authenticated_request("/grandchild/", self.superuser)
+        response = m.changelist_view(request)
+        self.assertNotContains(response, "Child object")
+        self.assertContains(response, "Parent object")
+
+    def test_list_display_related_field_uses_display_for_field(self):
+        # Related fields must be rendered with display_for_field(), not
+        # display_for_value(), so field-specific formatting, such as FileField
+        # links, is preserved.
+        genre = Genre.objects.create(name="Rock", file="documents/test.txt")
+        Musician.objects.create(name="John", genre=genre)
+
+        class MusicianAdmin(admin.ModelAdmin):
+            list_display = ["name", "genre__file"]
+
+        m = MusicianAdmin(Musician, custom_site)
+        request = self._mocked_authenticated_request("/musician/", self.superuser)
+        response = m.changelist_view(request)
+        self.assertContains(
+            response,
+            '<a href="/documents/test.txt">documents/test.txt</a>',
+            html=True,
+        )
+
     def test_list_display_related_field_boolean_display(self):
         """
         Related boolean fields (parent__is_active) display boolean icons.