Invalid app-name in INSTALLED_APPS leads to AppRegistryNotReady when testing

[HM]

When testing a standalone app, with a runtests.py like so:

import sys
import os

os.environ['DJANGO_SETTINGS_MODULE'] = 'app.tests.settings'

from django.conf import settings
from django.test.utils import get_runner

if __name__ == '__main__':
    from django import setup
    setup()

    TestRunner = get_runner(settings)

    test_runner = TestRunner()
    failures = test_runner.run_tests(settings.INSTALLED_APPS)

    if failures:
        sys.exit(bool(failures))

... and there is a typo in INSTALLED_APPS, instead of an ImportError pointing towards the wrong app-name there's an AppRegistryNotReady.

This holds for both 1.8.7 and 1.9.

[Tim Graham]

I can't reproduce this given the details you provided. Could you provide a sample project to reproduce it and reopen the ticket? Here's the traceback I see:

Traceback (most recent call last):
  File "runtests.py", line 11, in <module>
    setup()
  File "/home/tim/code/django/django/__init__.py", line 18, in setup
    apps.populate(settings.INSTALLED_APPS)
  File "/home/tim/code/django/django/apps/registry.py", line 85, in populate
    app_config = AppConfig.create(entry)
  File "/home/tim/code/django/django/apps/config.py", line 86, in create
    module = import_module(entry)
  File "/home/tim/.virtualenvs/django351/lib/python3.5/importlib/__init__.py", line 126, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 986, in _gcd_import
  File "<frozen importlib._bootstrap>", line 969, in _find_and_load
  File "<frozen importlib._bootstrap>", line 956, in _find_and_load_unlocked
ImportError: No module named 'xxx'