django/tests/apps/tests.py

from __future__ import absolute_import, unicode_literals

from contextlib import contextmanager
import os
import sys
from unittest import skipUnless

from django.apps import apps
from django.apps.registry import Apps
from django.core.exceptions import ImproperlyConfigured
from django.db import models
from django.test import TestCase, override_settings
from django.utils._os import upath
from django.utils import six

from .default_config_app.apps import CustomConfig
from .models import TotallyNormal, SoAlternative, new_apps


# Small list with a variety of cases for tests that iterate on installed apps.
# Intentionally not in alphabetical order to check if the order is preserved.

SOME_INSTALLED_APPS = [
    'apps.apps.MyAdmin',
    'apps.apps.MyAuth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
]

SOME_INSTALLED_APPS_NAMES = [
    'django.contrib.admin',
    'django.contrib.auth',
] + SOME_INSTALLED_APPS[2:]

HERE = os.path.dirname(__file__)


class AppsTests(TestCase):

    def test_singleton_master(self):
        """
        Ensures that only one master registry can exist.
        """
        with self.assertRaises(RuntimeError):
            Apps(installed_apps=None)

    def test_ready(self):
        """
        Tests the ready property of the master registry.
        """
        # The master app registry is always ready when the tests run.
        self.assertTrue(apps.ready)
        # Non-master app registries are populated in __init__.
        self.assertTrue(Apps().ready)

    def test_bad_app_config(self):
        """
        Tests when INSTALLED_APPS contains an incorrect app config.
        """
        with self.assertRaises(ImproperlyConfigured):
            with self.settings(INSTALLED_APPS=['apps.apps.BadConfig']):
                pass

    def test_not_an_app_config(self):
        """
        Tests when INSTALLED_APPS contains a class that isn't an app config.
        """
        with self.assertRaises(ImproperlyConfigured):
            with self.settings(INSTALLED_APPS=['apps.apps.NotAConfig']):
                pass

    def test_no_such_app(self):
        """
        Tests when INSTALLED_APPS contains an app that doesn't exist, either
        directly or via an app config.
        """
        with self.assertRaises(ImportError):
            with self.settings(INSTALLED_APPS=['there is no such app']):
                pass
        with self.assertRaises(ImportError):
            with self.settings(INSTALLED_APPS=['apps.apps.NoSuchApp']):
                pass

    def test_no_such_app_config(self):
        """
        Tests when INSTALLED_APPS contains an entry that doesn't exist.
        """
        with self.assertRaises(ImportError):
            with self.settings(INSTALLED_APPS=['apps.apps.NoSuchConfig']):
                pass

    def test_default_app_config(self):
        with self.settings(INSTALLED_APPS=['apps.default_config_app']):
            config = apps.get_app_config('default_config_app')
        self.assertIsInstance(config, CustomConfig)

    @override_settings(INSTALLED_APPS=SOME_INSTALLED_APPS)
    def test_get_app_configs(self):
        """
        Tests get_app_configs().
        """
        app_configs = apps.get_app_configs()
        self.assertListEqual(
            [app_config.name for app_config in app_configs],
            SOME_INSTALLED_APPS_NAMES)

    @override_settings(INSTALLED_APPS=SOME_INSTALLED_APPS)
    def test_get_app_config(self):
        """
        Tests get_app_config().
        """
        app_config = apps.get_app_config('admin')
        self.assertEqual(app_config.name, 'django.contrib.admin')

        app_config = apps.get_app_config('staticfiles')
        self.assertEqual(app_config.name, 'django.contrib.staticfiles')

        with self.assertRaises(LookupError):
            apps.get_app_config('webdesign')

    @override_settings(INSTALLED_APPS=SOME_INSTALLED_APPS)
    def test_is_installed(self):
        self.assertTrue(apps.is_installed('django.contrib.admin'))
        self.assertTrue(apps.is_installed('django.contrib.auth'))
        self.assertTrue(apps.is_installed('django.contrib.staticfiles'))
        self.assertFalse(apps.is_installed('django.contrib.webdesign'))

    @override_settings(INSTALLED_APPS=['apps.apps.RelabeledAppsConfig'])
    def test_relabeling(self):
        self.assertEqual(apps.get_app_config('relabeled').name, 'apps')

    def test_duplicate_labels(self):
        with six.assertRaisesRegex(self, ImproperlyConfigured, "Application labels aren't unique"):
            with self.settings(INSTALLED_APPS=['apps.apps.PlainAppsConfig', 'apps']):
                pass

    def test_duplicate_names(self):
        with six.assertRaisesRegex(self, ImproperlyConfigured, "Application names aren't unique"):
            with self.settings(INSTALLED_APPS=['apps.apps.RelabeledAppsConfig', 'apps']):
                pass

    def test_models_py(self):
        """
        Tests that the models in the models.py file were loaded correctly.
        """
        self.assertEqual(apps.get_model("apps", "TotallyNormal"), TotallyNormal)
        with self.assertRaises(LookupError):
            apps.get_model("apps", "SoAlternative")

        with self.assertRaises(LookupError):
            new_apps.get_model("apps", "TotallyNormal")
        self.assertEqual(new_apps.get_model("apps", "SoAlternative"), SoAlternative)

    def test_dynamic_load(self):
        """
        Makes a new model at runtime and ensures it goes into the right place.
        """
        old_models = list(apps.get_app_config("apps").get_models())
        # Construct a new model in a new app registry
        body = {}
        new_apps = Apps(["apps"])
        meta_contents = {
            'app_label': "apps",
            'apps': new_apps,
        }
        meta = type(str("Meta"), tuple(), meta_contents)
        body['Meta'] = meta
        body['__module__'] = TotallyNormal.__module__
        temp_model = type(str("SouthPonies"), (models.Model,), body)
        # Make sure it appeared in the right place!
        self.assertListEqual(list(apps.get_app_config("apps").get_models()), old_models)
        with self.assertRaises(LookupError):
            apps.get_model("apps", "SouthPonies")
        self.assertEqual(new_apps.get_model("apps", "SouthPonies"), temp_model)



@skipUnless(
    sys.version_info > (3, 3, 0),
    "Namespace packages sans __init__.py were added in Python 3.3")
class NamespacePackageAppTests(TestCase):
    # We need nsapp to be top-level so our multiple-paths tests can add another
    # location for it (if its inside a normal package with an __init__.py that
    # isn't possible). In order to avoid cluttering the already-full tests/ dir
    # (which is on sys.path), we add these new entries to sys.path temporarily.
    base_location = os.path.join(HERE, 'namespace_package_base')
    other_location = os.path.join(HERE, 'namespace_package_other_base')
    app_path = os.path.join(base_location, 'nsapp')

    @contextmanager
    def add_to_path(self, *paths):
        """Context manager to temporarily add paths to sys.path."""
        _orig_sys_path = sys.path[:]
        sys.path.extend(paths)
        try:
            yield
        finally:
            sys.path = _orig_sys_path

    def test_single_path(self):
        """
        A Py3.3+ namespace package can be an app if it has only one path.
        """
        with self.add_to_path(self.base_location):
            with self.settings(INSTALLED_APPS=['nsapp']):
                app_config = apps.get_app_config('nsapp')
                self.assertEqual(app_config.path, upath(self.app_path))

    def test_multiple_paths(self):
        """
        A Py3.3+ namespace package with multiple locations cannot be an app.

        (Because then we wouldn't know where to load its templates, static
        assets, etc from.)

        """
        # Temporarily add two directories to sys.path that both contain
        # components of the "nsapp" package.
        with self.add_to_path(self.base_location, self.other_location):
            with self.assertRaises(ImproperlyConfigured):
                with self.settings(INSTALLED_APPS=['nsapp']):
                    pass

    def test_multiple_paths_explicit_path(self):
        """
        Multiple locations are ok only if app-config has explicit path.
        """
        # Temporarily add two directories to sys.path that both contain
        # components of the "nsapp" package.
        with self.add_to_path(self.base_location, self.other_location):
            with self.settings(INSTALLED_APPS=['nsapp.apps.NSAppConfig']):
                app_config = apps.get_app_config('nsapp')
                self.assertEqual(app_config.path, upath(self.app_path))