Fixed #12546. Objects with a __len__ that returns 0 can now be serialized....

        return first_choice + list(self.flatchoices)

    def _get_val_from_obj(self, obj):

        if obj:

        if obj is not None:

            return getattr(obj, self.attname)

        else:

            return self.get_default()

class ExplicitInheritBaseModel(BaseModel):

    parent = models.OneToOneField(BaseModel)

    child_data = models.IntegerField()

class LengthModel(models.Model):

    data = models.IntegerField()

    def __len__(self):

        return self.data

"""

import unittest, datetime

import datetime

import decimal

import unittest

from cStringIO import StringIO

from django.utils.functional import curry

from django.conf import settings

from models import *

try:

    import decimal

except ImportError:

    from django.utils import _decimal as decimal

# A set of functions that can be used to recreate

# test data objects of various kinds.

    (data_obj, 1001, BigIntegerData, -9223372036854775808),

    (data_obj, 1002, BigIntegerData, 0),

    (data_obj, 1003, BigIntegerData, None),

    (data_obj, 1004, LengthModel, 0),

    (data_obj, 1005, LengthModel, 1),

]

# Because Oracle treats the empty string as NULL, Oracle is expected to fail