id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
26953	Custom manager inheriting BaseManager.from_queryset() crashes with AssertionError	Mikuláš Poul	nobody	"The unthinkable happened! 
{{{ 
Traceback (most recent call last):
  File ""manage.py"", line 14, in <module>
    execute_from_command_line(sys.argv)
  File ""{...}/local/lib/python2.7/site-packages/django/core/management/__init__.py"", line 350, in execute_from_command_line
    utility.execute()
  File ""{...}/local/lib/python2.7/site-packages/django/core/management/__init__.py"", line 324, in execute
    django.setup()
  File ""{...}/local/lib/python2.7/site-packages/django/__init__.py"", line 18, in setup
    apps.populate(settings.INSTALLED_APPS)
  File ""{...}/local/lib/python2.7/site-packages/django/apps/registry.py"", line 108, in populate
    app_config.import_models(all_models)
  File ""{...}/local/lib/python2.7/site-packages/django/apps/config.py"", line 202, in import_models
    self.models_module = import_module(models_module_name)
  File ""/usr/lib/python2.7/importlib/__init__.py"", line 37, in import_module
    __import__(name)
  File ""{...}/budgetter-app/apps/expense/models.py"", line 29, in <module>
    class Expense(models.Model):
  File ""{...}/local/lib/python2.7/site-packages/django/db/models/base.py"", line 283, in __new__
    new_class._prepare()
  File ""{...}/local/lib/python2.7/site-packages/django/db/models/base.py"", line 332, in _prepare
    ensure_default_manager(cls)
  File ""{...}/local/lib/python2.7/site-packages/django/db/models/manager.py"", line 45, in ensure_default_manager
    ""Should never get here. Please report a bug, including your ""
AssertionError: Should never get here. Please report a bug, including your model and model manager setup.

}}}

My model and manager setup

{{{#!python
from django.db import models
from django.db.models.manager import BaseManager
from django.db.models.query import QuerySet

class ExpenseQuerySet(QuerySet):
   pass

class ExpenseManager(BaseManager.from_queryset(ExpenseQuerySet)):
    pass

class Expense(models.Model):
    objects = ExpenseManager()
}}}"	Bug	closed	Database layer (models, ORM)	1.9	Normal	invalid		Loic Bistuer	Unreviewed	0	0	0	0	0	0