django/tests/db_functions/text/test_reverse.py

63 lines
2.2 KiB
Python

from django.db import connection
from django.db.models import CharField
from django.db.models.functions import Length, Reverse, Trim
from django.test import TestCase
from django.test.utils import register_lookup
from ..models import Author
class ReverseTests(TestCase):
@classmethod
def setUpTestData(cls):
cls.john = Author.objects.create(name="John Smith", alias="smithj")
cls.elena = Author.objects.create(name="Élena Jordan", alias="elena")
cls.python = Author.objects.create(name="パイソン")
def test_null(self):
author = Author.objects.annotate(backward=Reverse("alias")).get(
pk=self.python.pk
)
self.assertEqual(
author.backward,
"" if connection.features.interprets_empty_strings_as_nulls else None,
)
def test_basic(self):
authors = Author.objects.annotate(backward=Reverse("name"))
self.assertQuerysetEqual(
authors,
[
("John Smith", "htimS nhoJ"),
("Élena Jordan", "nadroJ anelÉ"),
("パイソン", "ンソイパ"),
],
lambda a: (a.name, a.backward),
ordered=False,
)
def test_transform(self):
with register_lookup(CharField, Reverse):
authors = Author.objects.all()
self.assertCountEqual(
authors.filter(name__reverse=self.john.name[::-1]), [self.john]
)
self.assertCountEqual(
authors.exclude(name__reverse=self.john.name[::-1]),
[self.elena, self.python],
)
def test_expressions(self):
author = Author.objects.annotate(backward=Reverse(Trim("name"))).get(
pk=self.john.pk
)
self.assertEqual(author.backward, self.john.name[::-1])
with register_lookup(CharField, Reverse), register_lookup(CharField, Length):
authors = Author.objects.all()
self.assertCountEqual(
authors.filter(name__reverse__length__gt=7), [self.john, self.elena]
)
self.assertCountEqual(
authors.exclude(name__reverse__length__gt=7), [self.python]
)