Add tests for foreign key reverse relations, and fix some issues. Still incomplete. ref deschler/django-modeltranslation#161

modeltranslation/fields.py

@@ -114,7 +114,11 @@ class TranslationField(object):
             import copy
             current = self.related.get_accessor_name()
             self.rel = copy.copy(self.rel)  # Since fields cannot share the same rel object.
+            self.related = copy.copy(self.related)
+            self.related.field = self  # We need self.related.field to point to this instance
             self.rel.related_name = build_localized_fieldname(current, self.language)
+            if hasattr(self.rel.to._meta, '_related_objects_cache'):
+                del self.rel.to._meta._related_objects_cache
 
     # Django 1.5 changed definition of __hash__ for fields to be fine with hash requirements.
     # It spoiled our machinery, since TranslationField has the same creation_counter as its

modeltranslation/tests/__init__.py

@@ -680,6 +680,76 @@ class ForeignKeyFieldsTest(ModeltranslationTestBase):
         self.failUnlessEqual(inst.optional_en_id, test_inst2.pk)
         self.failUnlessEqual(inst.optional_en.title, 'title2_en')
 
+    def test_reverse_relations(self):
+        test_inst = models.TestModel(title_en='title_en', title_de='title_de')
+        test_inst.save()
+
+        # Instantiate many 'ForeignKeyModel' instances:
+        fk_inst_both = models.ForeignKeyModel(test_de=test_inst, test_en=test_inst)
+        fk_inst_both.save()
+        fk_inst_de = models.ForeignKeyModel(test_de_id=test_inst.pk)
+        fk_inst_de.save()
+        fk_inst_en = models.ForeignKeyModel(test_en=test_inst)
+        fk_inst_en.save()
+
+        # Check that the reverse accessors are created on the model:
+        testmodel_fields = models.TestModel._meta.get_all_field_names()
+        self.assertIn('test_fks', testmodel_fields)
+        self.assertIn('test_fks_de', testmodel_fields)
+        self.assertIn('test_fks_en', testmodel_fields)
+        self.assertIn('foreignkeymodel_set', testmodel_fields)  # FIXME
+        self.assertIn('foreignkeymodel_set_de', testmodel_fields)
+        self.assertIn('foreignkeymodel_set_en', testmodel_fields)
+
+        # Check the german reverse accessor:
+        self.assertIn(fk_inst_both, test_inst.test_fks_de.all())
+        self.assertIn(fk_inst_de, test_inst.test_fks_de.all())
+        self.assertNotIn(fk_inst_en, test_inst.test_fks_de.all())
+
+        # Check the English reverse accessor:
+        self.assertIn(fk_inst_both, test_inst.test_fks_en.all())
+        self.assertIn(fk_inst_en, test_inst.test_fks_en.all())
+        self.assertNotIn(fk_inst_de, test_inst.test_fks_en.all())
+
+        # Check the default reverse accessor:
+        trans_real.activate("de")
+        self.assertIn(fk_inst_de,    test_inst.test_fks.all())
+        self.assertNotIn(fk_inst_en, test_inst.test_fks.all())
+        trans_real.activate("en")
+        self.assertIn(fk_inst_en,    test_inst.test_fks.all())
+        self.assertNotIn(fk_inst_de, test_inst.test_fks.all())
+
+        # Check filtering:
+        self.failUnlessEqual(models.TestModel.objects.filter(test_fks=fk_inst_de).count(), 1)
+        self.failUnlessEqual(models.TestModel.objects.filter(test_fks__id=fk_inst_de.pk).count(), 1)
+        self.failUnlessEqual(models.TestModel.objects.filter(test_fks=fk_inst_en).count(), 0)
+        self.failUnlessEqual(models.TestModel.objects.filter(test_fks_en=fk_inst_en).count(), 1)
+        trans_real.activate("en")
+        self.failUnlessEqual(models.TestModel.objects.filter(test_fks=fk_inst_en).count(), 1)  # FIXME
+        self.failUnlessEqual(models.TestModel.objects.filter(test_fks__id=fk_inst_en.pk).count(), 1)  # FIXME
+        self.failUnlessEqual(models.TestModel.objects.filter(test_fks=fk_inst_de).count(), 0)  # FIXME
+        # TODO: test filter() on a relation to a non-translated model  - FIXME
+
+        # Check assignment
+        trans_real.activate("de")
+        test_inst2 = models.TestModel(title_en='title_en', title_de='title_de')
+        test_inst2.save()
+        test_inst2.test_fks = [fk_inst_de, fk_inst_both]
+        test_inst2.test_fks_en = (fk_inst_en, fk_inst_both)
+
+        self.assertEqual(fk_inst_both.test.pk, test_inst2.pk)
+        self.assertEqual(fk_inst_both.test_id, test_inst2.pk)
+        self.assertEqual(fk_inst_both.test_de, test_inst2)
+        self.assertIn(fk_inst_both, test_inst2.test_fks_de.all())
+        self.assertIn(fk_inst_de, test_inst2.test_fks_de.all())
+        self.assertIn(fk_inst_de, test_inst2.test_fks.all())
+        self.assertNotIn(fk_inst_en, test_inst2.test_fks_de.all())
+        trans_real.activate("en")
+        self.assertIn(fk_inst_both, test_inst2.test_fks.all())
+        self.assertIn(fk_inst_en, test_inst2.test_fks.all())
+        self.assertNotIn(fk_inst_de, test_inst2.test_fks.all())
+        self.assertNotIn(fk_inst_de, test_inst2.test_fks_en.all())
+
 
 class OtherFieldsTest(ModeltranslationTestBase):
     def test_translated_models(self):

modeltranslation/tests/models.py

@@ -38,7 +38,7 @@ class FileFieldsModel(models.Model):
 ########## Foreign Key fields testing
 
 class ForeignKeyModel(models.Model):
-    test = models.ForeignKey(TestModel, null=True, related_name="test_fk")
+    test = models.ForeignKey(TestModel, null=True, related_name="test_fks")
     optional = models.ForeignKey(TestModel, blank=True, null=True)