Merge pull request #2151 from manfre/ticket-21746

from __future__ import unicode_literals

from django.db import connection

from django.test import TestCase

from .models import (Bar, Favorites, HiddenPointer, Place, Restaurant, Target,

            with self.assertRaises(UndergroundBar.DoesNotExist):

                p.undergroundbar

        # Several instances of the origin are only possible if database allows

        # inserting multiple NULL rows for a unique constraint

        if connection.features.ignores_nulls_in_unique_constraints:

            UndergroundBar.objects.create()

            # When there are several instances of the origin