[1.5.x] Fixed #16039 -- Made post_syncdb handlers multi-db aware.

Also reverted 8fb7a90026. Refs #17055.

Backport of a026e48 from master.

tests/regressiontests/multiple_database/tests.py

@@ -16,16 +16,6 @@ from django.utils.six import StringIO
 from .models import Book, Person, Pet, Review, UserProfile
 
 
-def copy_content_types_from_default_to_other():
-    # On post_syncdb, content types are created in the 'default' database.
-    # However, tests of generic foreign keys require them in 'other' too.
-    # The problem is masked on backends that defer constraints checks: at the
-    # end of each test, there's a rollback, and constraints are never checked.
-    # It only appears on MySQL + InnoDB.
-    for ct in ContentType.objects.using('default').all():
-        ct.save(using='other')
-
-
 class QueryTestCase(TestCase):
     multi_db = True
 
@@ -705,8 +695,6 @@ class QueryTestCase(TestCase):
 
     def test_generic_key_separation(self):
         "Generic fields are constrained to a single database"
-        copy_content_types_from_default_to_other()
-
         # Create a book and author on the default database
         pro = Book.objects.create(title="Pro Django",
                                   published=datetime.date(2008, 12, 16))
@@ -734,8 +722,6 @@ class QueryTestCase(TestCase):
 
     def test_generic_key_reverse_operations(self):
         "Generic reverse manipulations are all constrained to a single DB"
-        copy_content_types_from_default_to_other()
-
         dive = Book.objects.using('other').create(title="Dive into Python",
                                                   published=datetime.date(2009, 5, 4))
 
@@ -780,8 +766,6 @@ class QueryTestCase(TestCase):
 
     def test_generic_key_cross_database_protection(self):
         "Operations that involve sharing generic key objects across databases raise an error"
-        copy_content_types_from_default_to_other()
-
         # Create a book and author on the default database
         pro = Book.objects.create(title="Pro Django",
                                   published=datetime.date(2008, 12, 16))
@@ -833,8 +817,6 @@ class QueryTestCase(TestCase):
 
     def test_generic_key_deletion(self):
         "Cascaded deletions of Generic Key relations issue queries on the right database"
-        copy_content_types_from_default_to_other()
-
         dive = Book.objects.using('other').create(title="Dive into Python",
                                                   published=datetime.date(2009, 5, 4))
         review = Review.objects.using('other').create(source="Python Weekly", content_object=dive)
@@ -1402,8 +1384,6 @@ class RouterTestCase(TestCase):
 
     def test_generic_key_cross_database_protection(self):
         "Generic Key operations can span databases if they share a source"
-        copy_content_types_from_default_to_other()
-
         # Create a book and author on the default database
         pro = Book.objects.using('default'
                 ).create(title="Pro Django", published=datetime.date(2008, 12, 16))
@@ -1515,8 +1495,6 @@ class RouterTestCase(TestCase):
 
     def test_generic_key_managers(self):
         "Generic key relations are represented by managers, and can be controlled like managers"
-        copy_content_types_from_default_to_other()
-
         pro = Book.objects.using('other').create(title="Pro Django",
                                                  published=datetime.date(2008, 12, 16))
 
@@ -1922,3 +1900,36 @@ class RouterModelArgumentTestCase(TestCase):
         pet = Pet.objects.create(owner=person, name='Wart')
         # test related FK collection
         person.delete()
+
+
+class SyncOnlyDefaultDatabaseRouter(object):
+    def allow_syncdb(self, db, model):
+        return db == DEFAULT_DB_ALIAS
+
+
+class SyncDBTestCase(TestCase):
+    multi_db = True
+
+    def test_syncdb_to_other_database(self):
+        """Regression test for #16039: syncdb with --database option."""
+        count = ContentType.objects.count()
+        self.assertGreater(count, 0)
+
+        ContentType.objects.using('other').delete()
+        management.call_command('syncdb', verbosity=0, interactive=False,
+            load_initial_data=False, database='other')
+
+        self.assertEqual(ContentType.objects.using("other").count(), count)
+
+    def test_syncdb_to_other_database_with_router(self):
+        """Regression test for #16039: syncdb with --database option."""
+        ContentType.objects.using('other').delete()
+        try:
+            old_routers = router.routers
+            router.routers = [SyncOnlyDefaultDatabaseRouter()]
+            management.call_command('syncdb', verbosity=0, interactive=False,
+                load_initial_data=False, database='other')
+        finally:
+            router.routers = old_routers
+
+        self.assertEqual(ContentType.objects.using("other").count(), 0)