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# coding: utf-8
"""
Tests for some corner cases with deleting.
"""
from django.db import models
class DefaultRepr(object):
def __repr__(self):
return u"<%s: %s>" % (self.__class__.__name__, self.__dict__)
class A(DefaultRepr, models.Model):
pass
class B(DefaultRepr, models.Model):
a = models.ForeignKey(A)
class C(DefaultRepr, models.Model):
b = models.ForeignKey(B)
class D(DefaultRepr, models.Model):
c = models.ForeignKey(C)
a = models.ForeignKey(A)
# Simplified, we have:
# A
# B -> A
# C -> B
# D -> C
# D -> A
# So, we must delete Ds first of all, then Cs then Bs then As.
# However, if we start at As, we might find Bs first (in which
# case things will be nice), or find Ds first.
# Some mutually dependent models, but nullable
class E(DefaultRepr, models.Model):
f = models.ForeignKey('F', null=True, related_name='e_rel')
class F(DefaultRepr, models.Model):
e = models.ForeignKey(E, related_name='f_rel')
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