Error when creating max-migration file

[mrswats]

Hello again!

The update worked pretty well, now I ran into another problem.

I tried to create said file for all my django apps with the following result:

$ poetry run ./manage.py create-max-migration-files
Created max_migration.txt for tracker
Traceback (most recent call last):
  File "./manage.py", line 39, in <module>
    manage()
  File "./manage.py", line 35, in manage
    execute_from_command_line(sys.argv)
  File "/home/fjm/.cache/pypoetry/virtualenvs/price-tracker-XfPLBuU3-py3.8/lib/python3.8/site-packages/django/core/management/__init__.py", line 381, in execute_from_command_line
    utility.execute()
  File "/home/fjm/.cache/pypoetry/virtualenvs/price-tracker-XfPLBuU3-py3.8/lib/python3.8/site-packages/django/core/management/__init__.py", line 375, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "/home/fjm/.cache/pypoetry/virtualenvs/price-tracker-XfPLBuU3-py3.8/lib/python3.8/site-packages/django/core/management/base.py", line 323, in run_from_argv
    self.execute(*args, **cmd_options)
  File "/home/fjm/.cache/pypoetry/virtualenvs/price-tracker-XfPLBuU3-py3.8/lib/python3.8/site-packages/django/core/management/base.py", line 364, in execute
    output = self.handle(*args, **options)
  File "/home/fjm/.cache/pypoetry/virtualenvs/price-tracker-XfPLBuU3-py3.8/lib/python3.8/site-packages/django_linear_migrations/management/commands/create-max-migration-files.py", line 46, in handle
    max_migration_txt = migration_details.dir / "max_migration.txt"
  File "/home/fjm/.cache/pypoetry/virtualenvs/price-tracker-XfPLBuU3-py3.8/lib/python3.8/site-packages/django/utils/functional.py", line 80, in __get__
    res = instance.__dict__[self.name] = self.func(instance)
  File "/home/fjm/.cache/pypoetry/virtualenvs/price-tracker-XfPLBuU3-py3.8/lib/python3.8/site-packages/django_linear_migrations/apps.py", line 62, in dir
    return Path(self.migrations_module.__file__).parent
AttributeError: 'NoneType' object has no attribute '__file__'

However, it looks like I can do it for individual apps appending the app name at the end without problem.

This time around it has a workaround so it's not so pressing but something to consider.

Thank you!

[adamchainz]

Fixed in #14, released in 1.0.2. Thanks again.