Fixed test for https://github.com/hmarr/mongoengine/pull/362

gistfile1.py

# -*- coding: utf-8

from unittest import TestCase
import unittest
from mongoengine import connect, Document, StringField, IntField, FloatField, \
     ComplexDateTimeField
import datetime

class Test(TestCase):
    def setUp(self):
        connect('mongenginetest')

    def test_1(self):
        """Ensure that every fields should accept None if required is False.
        """

        class AllFields(Document):
            str_fld = StringField()
            int_fld = IntField()
            flt_fld = FloatField()
            comp_dt_fld = ComplexDateTimeField()

        doc = AllFields()
        doc.str_fld = u'spam ham egg'
        doc.int_fld = 42
        doc.flt_fld = 4.2
        doc.com_dt_fld = datetime.datetime.utcnow()
        doc.save()

        res = AllFields.objects(id=doc.id).update(
            set__str_fld=None,
            set__int_fld=None,
            set__flt_fld=None,
            set__comp_dt_fld=None,
            )
        self.assertEqual(res, 1)

        # Retrive data from db and verify it.
        ret = AllFields.objects.all()[0]

        self.assertEqual(ret.str_fld, None)
        self.assertEqual(ret.int_fld, None)
        self.assertEqual(ret.flt_fld, None)
        # Return current time if retrived value is None.
        self.assert_(isinstance(ret.comp_dt_fld, datetime.datetime))

        AllFields.drop_collection()

        return

if __name__ == '__main__':
    unittest.main()