Fix django#19524 -- Incorrect caching of parents of unsaved model instances.

Thanks qcwxezdas for the report. Refs django#13839.

Author: aaugustin

django/db/models/base.py

@@ -583,6 +583,15 @@ def save_base(self, raw=False, cls=None, origin=None, force_insert=False,
 
  if field:
  setattr(self, field.attname, self._get_pk_val(parent._meta))
+ # Since we didn't have an instance of the parent handy, we
+ # set attname directly, bypassing the descriptor.
+ # Invalidate the related object cache, in case it's been
+ # accidentally populated. A fresh instance will be
+ # re-built from the database if necessary.
+ cache_name = field.get_cache_name()
+ if hasattr(self, cache_name):
+ delattr(self, cache_name)
+
  if meta.proxy:
  return
 

django/forms/models.py

@@ -692,7 +692,10 @@ def __init__(self, data=None, files=None, instance=None,
  self.rel_name = RelatedObject(self.fk.rel.to, self.model, self.fk).get_accessor_name()
  if queryset is None:
  queryset = self.model._default_manager
- qs = queryset.filter(**{self.fk.name: self.instance})
+ if self.instance.pk:
+ qs = queryset.filter(**{self.fk.name: self.instance})
+ else:
+ qs = queryset.none()
  super(BaseInlineFormSet, self).__init__(data, files, prefix=prefix,
  queryset=qs, **kwargs)
 

tests/regressiontests/admin_inlines/admin.py

@@ -124,6 +124,9 @@ class ChildModel1Inline(admin.TabularInline):
 class ChildModel2Inline(admin.StackedInline):
  model = ChildModel2
 
+# admin for #19524
+class SightingInline(admin.TabularInline):
+ model = Sighting
 
 site.register(TitleCollection, inlines=[TitleInline])
 # Test bug #12561 and #12778
@@ -141,4 +144,5 @@ class ChildModel2Inline(admin.StackedInline):
 site.register(Author, AuthorAdmin)
 site.register(CapoFamiglia, inlines=[ConsigliereInline, SottoCapoInline])
 site.register(ProfileCollection, inlines=[ProfileInline])
-site.register(ParentModelWithCustomPk, inlines=[ChildModel1Inline, ChildModel2Inline])
+site.register(ParentModelWithCustomPk, inlines=[ChildModel1Inline, ChildModel2Inline])
+site.register(ExtraTerrestrial, inlines=[SightingInline])

tests/regressiontests/admin_inlines/models.py

@@ -90,7 +90,6 @@ class Inner4Tabular(models.Model):
  dummy = models.IntegerField(help_text="Awesome tabular help text is awesome.")
  holder = models.ForeignKey(Holder4)
 
-
 # Models for #12749
 
 class Person(models.Model):
@@ -133,6 +132,7 @@ class Chapter(models.Model):
 
 
 # Models for #16838
+
 class CapoFamiglia(models.Model):
  name = models.CharField(max_length=100)
 
@@ -170,6 +170,17 @@ class ChildModel2(models.Model):
  def get_absolute_url(self):
  return '/child_model2/'
 
+# Models for #19524
+
+class LifeForm(models.Model):
+ pass
+
+class ExtraTerrestrial(LifeForm):
+ name = models.CharField(max_length=100)
+
+class Sighting(models.Model):
+ et = models.ForeignKey(ExtraTerrestrial)
+ place = models.CharField(max_length=100)
 
 # Other models
 

tests/regressiontests/admin_inlines/tests.py

@@ -12,7 +12,7 @@
 from .models import (Holder, Inner, Holder2, Inner2, Holder3, Inner3, Person,
  OutfitItem, Fashionista, Teacher, Parent, Child, Author, Book, Profile,
  ProfileCollection, ParentModelWithCustomPk, ChildModel1, ChildModel2,
- Title)
+ Sighting, Title)
 
 
 @override_settings(PASSWORD_HASHERS=('django.contrib.auth.hashers.SHA1PasswordHasher',))
@@ -172,6 +172,23 @@ def test_custom_pk_shortcut(self):
  self.assertContains(response, child1_shortcut)
  self.assertContains(response, child2_shortcut)
 
+ def test_create_inlines_on_inherited_model(self):
+ """
+ Ensure that an object can be created with inlines when it inherits
+ another class. Bug #19524.
+ """
+ data = {
+ 'name': 'Martian',
+ 'sighting_set-TOTAL_FORMS': 1,
+ 'sighting_set-INITIAL_FORMS': 0,
+ 'sighting_set-MAX_NUM_FORMS': 0,
+ 'sighting_set-0-place': 'Zone 51',
+ '_save': 'Save',
+ }
+ response = self.client.post('/admin/admin_inlines/extraterrestrial/add/', data)
+ self.assertEqual(response.status_code, 302)
+ self.assertEqual(Sighting.objects.filter(et__name='Martian').count(), 1)
+
 
 @override_settings(PASSWORD_HASHERS=('django.contrib.auth.hashers.SHA1PasswordHasher',))
 class TestInlineMedia(TestCase):