Ticket #16433: django-16433-with-test.patch

django/contrib/admin/util.py

@@ -304 +304 @@
 def help_text_for_field(name, model):
     try:
         help_text = model._meta.get_field_by_name(name)[0].help_text
-    except models.FieldDoesNotExist:
+    except (models.FieldDoesNotExist, AttributeError):
         help_text = ""
     return smart_unicode(help_text)
 

tests/regressiontests/admin_views/admin.py

@@ -411 +411 @@
     def get_changelist(self, request, **kwargs):
         return CustomChangeList
 
+class ToppingAdmin(admin.ModelAdmin):
+    readonly_fields = ('pizzas',)
 
 class PizzaAdmin(admin.ModelAdmin):
     readonly_fields = ('toppings',)
@@ -630 +632 @@
 site.register(Promo)
 site.register(ChapterXtra1, ChapterXtra1Admin)
 site.register(Pizza, PizzaAdmin)
-site.register(Topping)
+site.register(Topping, ToppingAdmin)
 site.register(Album, AlbumAdmin)
 site.register(Question)
 site.register(Answer)

tests/regressiontests/admin_views/tests.py

@@ -42 +42 @@
     FoodDelivery, RowLevelChangePermissionModel, Paper, CoverLetter, Story,
     OtherStory, ComplexSortedPerson, Parent, Child, AdminOrderedField,
     AdminOrderedModelMethod, AdminOrderedAdminMethod, AdminOrderedCallable,
-    Report, MainPrepopulated, RelatedPrepopulated, UnorderedObject)
+    Report, MainPrepopulated, RelatedPrepopulated, UnorderedObject, Pizza, Topping)
 
 
 ERROR_MESSAGE = "Please enter the correct username and password \
@@ -3104 +3104 @@
         response = self.client.get('/test_admin/admin2/auth/user/%s/password/' % su.pk)
         self.assertEquals(response.status_code, 404)
 
+    def test_readonly_backwards_ref(self):
+        """Regression test for #16433 - backwards references for related objects
+        break if the related field is read-only - due to the .help_text attribute
+        """
+        topping = Topping.objects.create(name='Salami')
+        pizza = Pizza.objects.create(name='Americano')
+        pizza.toppings.add(topping)
+        response = self.client.get('/test_admin/admin/admin_views/topping/add/')
+        self.assertEqual(response.status_code, 200)
 
+
 class RawIdFieldsTest(TestCase):
     urls = "regressiontests.admin_views.urls"
     fixtures = ['admin-views-users.xml']

tests/regressiontests/admin_views/models.py

@@ -455 +455 @@
 class Topping(models.Model):
     name = models.CharField(max_length=20)
 
-
 class Pizza(models.Model):
     name = models.CharField(max_length=20)
-    toppings = models.ManyToManyField('Topping')
+    toppings = models.ManyToManyField('Topping', related_name='pizzas')
 
 
 class Album(models.Model):