Fixed #29682 -- Fixed admin change form crash if a view-only model's form has an extra field.

tests/admin_utils/tests.py

@@ -286,6 +286,22 @@ class UtilsTests(SimpleTestCase):
             ("not Really the Model", MockModelAdmin.test_from_model)
         )
 
+    def test_label_for_field_form_argument(self):
+        class ArticleForm(forms.ModelForm):
+            extra_form_field = forms.BooleanField()
+
+            class Meta:
+                fields = '__all__'
+                model = Article
+
+        self.assertEqual(
+            label_for_field('extra_form_field', Article, form=ArticleForm()),
+            'Extra form field'
+        )
+        msg = "Unable to lookup 'nonexistent' on Article or ArticleForm"
+        with self.assertRaisesMessage(AttributeError, msg):
+            label_for_field('nonexistent', Article, form=ArticleForm()),
+
     def test_label_for_property(self):
         # NOTE: cannot use @property decorator, because of
         # AttributeError: 'property' object has no attribute 'short_description'

tests/admin_views/admin.py

@@ -91,6 +91,14 @@ class ChapterXtra1Admin(admin.ModelAdmin):
     )
 
 
+class ArticleForm(forms.ModelForm):
+    extra_form_field = forms.BooleanField(required=False)
+
+    class Meta:
+        fields = '__all__'
+        model = Article
+
+
 class ArticleAdmin(admin.ModelAdmin):
     list_display = (
         'content', 'date', callable_year, 'model_year', 'modeladmin_year',
@@ -101,10 +109,11 @@ class ArticleAdmin(admin.ModelAdmin):
     list_filter = ('date', 'section')
     autocomplete_fields = ('section',)
     view_on_site = False
+    form = ArticleForm
     fieldsets = (
         ('Some fields', {
             'classes': ('collapse',),
-            'fields': ('title', 'content')
+            'fields': ('title', 'content', 'extra_form_field'),
         }),
         ('Some other fields', {
             'classes': ('wide',),

tests/admin_views/tests.py

@@ -1768,6 +1768,7 @@ class AdminViewPermissionsTest(TestCase):
         response = self.client.get(article_change_url)
         self.assertEqual(response.status_code, 200)
         self.assertEqual(response.context['title'], 'View article')
+        self.assertContains(response, '<label>Extra form field:</label>')
         self.assertContains(response, '<a href="/test_admin/admin/admin_views/article/" class="closelink">Close</a>')
         post = self.client.post(article_change_url, change_dict)
         self.assertEqual(post.status_code, 302)