[1.5.x] Fixed #19806 -- Ensure that content types and permissions aren't created for swapped models.

Thanks to rizumu for the report.

Backport of c8985a8a73.

tests/regressiontests/swappable_models/tests.py

@@ -0,0 +1,46 @@
+from __future__ import absolute_import, unicode_literals
+
+from django.utils.six import StringIO
+
+from django.contrib.auth.models import Permission
+from django.contrib.contenttypes.models import ContentType
+from django.core import management
+from django.db.models.loading import cache
+from django.test import TestCase
+from django.test.utils import override_settings
+
+
+class SwappableModelTests(TestCase):
+    def setUp(self):
+        # This test modifies the installed apps, so we need to make sure
+        # we're not dealing with a cached app list.
+        cache._get_models_cache.clear()
+
+    def tearDown(self):
+        # By fiddling with swappable models, we alter the installed models
+        # cache, so flush it to make sure there are no side effects.
+        cache._get_models_cache.clear()
+
+    @override_settings(TEST_ARTICLE_MODEL='swappable_models.AlternateArticle')
+    def test_generated_data(self):
+        "Permissions and content types are not created for a swapped model"
+
+        # Delete all permissions and content_types
+        Permission.objects.all().delete()
+        ContentType.objects.all().delete()
+
+        # Re-run syncdb. This will re-build the permissions and content types.
+        new_io = StringIO()
+        management.call_command('syncdb', load_initial_data=False, interactive=False, stdout=new_io)
+
+        # Check that content types and permissions exist for the swapped model,
+        # but not for the swappable model.
+        apps_models = [(p.content_type.app_label, p.content_type.model)
+                       for p in Permission.objects.all()]
+        self.assertIn(('swappable_models', 'alternatearticle'), apps_models)
+        self.assertNotIn(('swappable_models', 'article'), apps_models)
+
+        apps_models = [(ct.app_label, ct.model)
+                       for ct in ContentType.objects.all()]
+        self.assertIn(('swappable_models', 'alternatearticle'), apps_models)
+        self.assertNotIn(('swappable_models', 'article'), apps_models)