CircularDependencyError in migrations

[Gabe Jackson]

django.db.migrations.graph.CircularDependencyError

Test Project is located here: ​https://github.com/gabejackson/django-migration-test/tree/circ_dep_1

Steps to reproduce:
Install stable/1.7.x branch in venv
./manage.py makemigrations
... [OK]
./manage.py migrate

Traceback (most recent call last):
  File "./manage.py", line 10, in <module>
    execute_from_command_line(sys.argv)
  File "/Users/gabejackson/venv/django-1.7/src/django/django/core/management/__init__.py", line 385, in execute_from_command_line
    utility.execute()
  File "/Users/gabejackson/venv/django-1.7/src/django/django/core/management/__init__.py", line 377, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "/Users/gabejackson/venv/django-1.7/src/django/django/core/management/base.py", line 288, in run_from_argv
    self.execute(*args, **options.__dict__)
  File "/Users/gabejackson/venv/django-1.7/src/django/django/core/management/base.py", line 338, in execute
    output = self.handle(*args, **options)
  File "/Users/gabejackson/venv/django-1.7/src/django/django/core/management/commands/migrate.py", line 106, in handle
    plan = executor.migration_plan(targets)
  File "/Users/gabejackson/venv/django-1.7/src/django/django/db/migrations/executor.py", line 49, in migration_plan
    for migration in self.loader.graph.forwards_plan(target):
  File "/Users/gabejackson/venv/django-1.7/src/django/django/db/migrations/graph.py", line 55, in forwards_plan
    return self.dfs(node, lambda x: self.dependencies.get(x, set()))
  File "/Users/gabejackson/venv/django-1.7/src/django/django/db/migrations/graph.py", line 121, in dfs
    return _dfs(start, get_children, [])
  File "/Users/gabejackson/venv/django-1.7/src/django/django/db/migrations/graph.py", line 113, in _dfs
    results = _dfs(n, get_children, path) + results
  File "/Users/gabejackson/venv/django-1.7/src/django/django/db/migrations/graph.py", line 113, in _dfs
    results = _dfs(n, get_children, path) + results
  File "/Users/gabejackson/venv/django-1.7/src/django/django/db/migrations/graph.py", line 113, in _dfs
    results = _dfs(n, get_children, path) + results
  File "/Users/gabejackson/venv/django-1.7/src/django/django/db/migrations/graph.py", line 113, in _dfs
    results = _dfs(n, get_children, path) + results
  File "/Users/gabejackson/venv/django-1.7/src/django/django/db/migrations/graph.py", line 105, in _dfs
    raise CircularDependencyError(path[path.index(start):] + [start])
django.db.migrations.graph.CircularDependencyError: [(u'a', u'0001_initial'), ('c', u'0001_initial'), (u'b', u'0001_initial'), (u'a', u'0001_initial')]

[Gabe Jackson]

Added a Graph of the Models if that helps anybody: ​https://github.com/gabejackson/django-migration-test/blob/circ_dep_1/models.pdf

[Markus Holtermann]

I can confirm the bug. I'm working on a fix.

[Baptiste Mispelon]

Accepting per previous comment.

[Markus Holtermann]

Here's the pull request. Needs some tests though: ​https://github.com/django/django/pull/3093

[Andrew Godwin]

Without a small test case writing a test is going to be very hard. I can have a go if you're willing to assign the ticket to me.

[Markus Holtermann]

Tests are there.

[Tim Graham <timograham@…>]

In 144cff3f516f7c718cbe4bd3165e18781c09042a:

Fixed #23322 -- Use resolved swappable model for dependency resolution during makemigrations

[Tim Graham <timograham@…>]

In 2da20379c0dd0171eb11c188909096f708dd6095:

[1.7.x] Fixed #23322 -- Use resolved swappable model for dependency resolution during makemigrations

Backport of 144cff3f51 from master

[Tim Graham <timograham@…>]

In f1855fd8:

Refs #23322 -- Removed unnecessary "and" clause in the autodetector.

If the depedency was swappable then it'll be resolved at this point.