1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
|
from django.db import connection
from django.db.models import Value
from django.db.models.functions import Length, LPad, RPad
from django.test import TestCase
from ..models import Author
class PadTests(TestCase):
def test_pad(self):
Author.objects.create(name='John', alias='j')
none_value = '' if connection.features.interprets_empty_strings_as_nulls else None
tests = (
(LPad('name', 7, Value('xy')), 'xyxJohn'),
(RPad('name', 7, Value('xy')), 'Johnxyx'),
(LPad('name', 6, Value('x')), 'xxJohn'),
(RPad('name', 6, Value('x')), 'Johnxx'),
# The default pad string is a space.
(LPad('name', 6), ' John'),
(RPad('name', 6), 'John '),
# If string is longer than length it is truncated.
(LPad('name', 2), 'Jo'),
(RPad('name', 2), 'Jo'),
(LPad('name', 0), ''),
(RPad('name', 0), ''),
(LPad('name', None), none_value),
(RPad('name', None), none_value),
(LPad('goes_by', 1), none_value),
(RPad('goes_by', 1), none_value),
)
for function, padded_name in tests:
with self.subTest(function=function):
authors = Author.objects.annotate(padded_name=function)
self.assertQuerysetEqual(authors, [padded_name], lambda a: a.padded_name, ordered=False)
def test_pad_negative_length(self):
for function in (LPad, RPad):
with self.subTest(function=function):
with self.assertRaisesMessage(ValueError, "'length' must be greater or equal to 0."):
function('name', -1)
def test_combined_with_length(self):
Author.objects.create(name='Rhonda', alias='john_smith')
Author.objects.create(name='♥♣♠', alias='bytes')
authors = Author.objects.annotate(filled=LPad('name', Length('alias')))
self.assertQuerysetEqual(
authors.order_by('alias'),
[' ♥♣♠', ' Rhonda'],
lambda a: a.filled,
)
|
