Unexpected fake_initial keyword thrown on migration

[Yuval Adam]

We've recently migrated a Django 1.7 project to 1.8.7. When running migrations we get the following error:

Running migrations:
Traceback (most recent call last):
  File "manage.py", line 11, in <module>
    execute_from_command_line(sys.argv)
  File "/opt/python/run/venv/local/lib/python2.7/site-packages/django/core/management/__init__.py", line 354, in execute_from_command_line
    utility.execute()
  File "/opt/python/run/venv/local/lib/python2.7/site-packages/django/core/management/__init__.py", line 346, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "/opt/python/run/venv/local/lib/python2.7/site-packages/django/core/management/base.py", line 394, in run_from_argv
    self.execute(*args, **cmd_options)
  File "/opt/python/run/venv/local/lib/python2.7/site-packages/django/core/management/base.py", line 445, in execute
    output = self.handle(*args, **options)
  File "/opt/python/run/venv/local/lib/python2.7/site-packages/django/core/management/commands/migrate.py", line 222, in handle
    executor.migrate(targets, plan, fake=fake, fake_initial=fake_initial)
TypeError: migrate() got an unexpected keyword argument 'fake_initial'

This happens even on a clean DB. We tried disabling all third party apps, as well as all our internal apps, and no dice. The weird thing is this happens only with DEBUG=False, while running migrate with DEBUG=True succeeds.

There doesn't seem to be any mention of this traceback up until now anywhere not in the tickets and not even when googling this error. How can we further debug this problem?

[Tim Graham]

You can provide a sample project to reproduce the error and/or see TicketClosingReasons/UseSupportChannels. Thanks!

[Yuval Adam]

It'll be very hard to provide a repro sample since this is a very large project with many different migrations.

Even if this isn't a Django bug, the traceback in this case should be more descriptive. As of now I have no idea how to further debug other than temporarily running with DEBUG=True on production as a workaround.

[Yuval Adam]

We got a hint from a fellow Django core dev (thanks Shai!) that this might be related to stale *.pyc files hanging around. Initial test show that this indeed might be the problem.