Make utils.local_import check INSTALLED_APPS for compound paths

 - Checks all possible iterations of app name against `INSTALLED_APPS`, so `app.sub_app.module.Class` checks `INSTALLED_APPS` for `app.sub_app.module`, then `app.sub_app`, then `app`, instead of just checking for `app`. - Adds test to characterize new import behavior. - Fixes issue #13

Author: voxy-pairstation

rest_framework_serializer_extensions/utils.py

@@ -15,9 +15,14 @@ def import_local(path_to_object):
  """
  path, name = path_to_object.rsplit('.', 1)
 
- app = path.split('.')[0]
-
- if app not in settings.INSTALLED_APPS:
+ path_pieces = path.split('.')
+ while path_pieces:
+ if '.'.join(path_pieces) not in settings.INSTALLED_APPS:
+ path_pieces.pop()
+ else:
+ break
+
+ if not path_pieces:
  raise AssertionError(
  "Cannot import from outside installed apps"
  )

test_package/__init__.py

@@ -0,0 +1,2 @@
+class TestSerializer(object):
+ pass

test_package/test_module/__init__.py

@@ -34,6 +34,7 @@ def pytest_configure():
  'rest_framework.authtoken',
  'rest_framework_serializer_extensions',
  'tests',
+ 'test_package.test_module',
  ),
  PASSWORD_HASHERS=(
  'django.contrib.auth.hashers.SHA1PasswordHasher',

test_package/test_module/serializers.py

@@ -4,6 +4,7 @@
 from django.test import override_settings, TestCase
 
 from rest_framework_serializer_extensions import fields, utils
+from test_package.test_module.serializers import TestSerializer
 from tests import models
 from tests.base import TEST_HASH_IDS
 
@@ -30,6 +31,12 @@ def test_import_within_installed_apps(self):
  )
  self.assertIs(imported, fields.HashIdField)
 
+ def test_import_complex_path_within_installed_apps(self):
+ imported = utils.import_local(
+ 'test_package.test_module.serializers.TestSerializer'
+ )
+ self.assertIs(imported, TestSerializer)
+
 
 class GetSettingTests(TestCase):
  """