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
22051	Running `makemigrations` twice in a row fails	Baptiste Mispelon	Andrew Godwin	"With the following (slightly contrived but still valid) models (taken from #22047):
{{{#!python
from django.contrib.auth.models import User, Group
from django.db import models

class MyGroup(Group):
    users = models.ManyToManyField('bug22047.MyUser', through='Membership')


class MyUser(User):
    pass


class Membership(models.Model):
    user = models.ForeignKey(MyUser)
    group = models.ForeignKey(MyGroup)
}}}

Running `manage.py makemigrations` for the first time works, but running it immediately after raises this error:
{{{
Traceback (most recent call last):
  File ""manage.py"", line 10, in <module>
    execute_from_command_line(sys.argv)
  File ""./django/core/management/__init__.py"", line 427, in execute_from_command_line
    utility.execute()
  File ""./django/core/management/__init__.py"", line 419, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File ""./django/core/management/base.py"", line 287, in run_from_argv
    self.execute(*args, **options.__dict__)
  File ""./django/core/management/base.py"", line 336, in execute
    output = self.handle(*args, **options)
  File ""./django/core/management/commands/makemigrations.py"", line 99, in handle
    changes = autodetector.changes(graph=loader.graph, trim_to_apps=app_labels or None)
  File ""./django/db/migrations/autodetector.py"", line 33, in changes
    changes = self._detect_changes()
  File ""./django/db/migrations/autodetector.py"", line 50, in _detect_changes
    old_apps = self.from_state.render()
  File ""./django/db/migrations/state.py"", line 52, in render
    raise InvalidBasesError(""Cannot resolve bases for %r"" % new_unrendered_models)
django.db.migrations.state.InvalidBasesError: Cannot resolve bases for [<django.db.migrations.state.ModelState object at 0x7f2353215e90>, <django.db.migrations.state.ModelState object at 0x7f23531b7350>]

}}}"	Bug	closed	Migrations	dev	Release blocker	fixed		numerodix@…	Accepted	0	0	0	0	0	0