def test_basic(self):
Author.objects.create(name='John', alias='xyz')
tests = (
(Repeat('name', 0), ''),
(Repeat('name', 2), 'JohnJohn'),
(Repeat('name', Length('alias'), output_field=CharField()), 'JohnJohnJohn'),
(Repeat(Value('x'), 3, output_field=CharField()), 'xxx'),
)
for function, repeated_text in tests:
with self.subTest(function=function):
authors = Author.objects.annotate(repeated_text=function)
self.assertQuerysetEqual(authors, [repeated_text], lambda a: a.repeated_text, ordered=False)
def test_filter_with_expr(self):
# contains uses the UUID rather tan the ShortUUID
self.assertSequenceEqual(
NullableShortUUIDModel.objects.annotate(
value=Concat(Value('8400'),
Value('e29b'),
output_field=CharField()), ).filter(
field__contains=F('value')),
[self.objs[1]],
)
self.assertSequenceEqual(
NullableShortUUIDModel.objects.annotate(value=Concat(
Value('8400'),
Value('-'),
Value('e29b'),
output_field=CharField()), ).filter(
field__contains=F('value')),
[self.objs[1]],
)
self.assertSequenceEqual(
NullableShortUUIDModel.objects.annotate(value=Repeat(
Value('0'), 2, output_field=CharField()), ).filter(
field__contains=F('value')),
[self.objs[1]],
)
def test_filter_with_expr(self):
self.assertSequenceEqualWithoutHyphens(
NullableUUIDModel.objects.annotate(
value=Concat(Value('8400'), Value('e29b'), output_field=CharField()),
).filter(field__contains=F('value')),
[self.objs[1]],
)
self.assertSequenceEqual(
NullableUUIDModel.objects.annotate(
value=Concat(Value('8400'), Value('-'), Value('e29b'), output_field=CharField()),
).filter(field__contains=F('value')),
[self.objs[1]],
)
self.assertSequenceEqual(
NullableUUIDModel.objects.annotate(
value=Repeat(Value('0'), 4, output_field=CharField()),
).filter(field__contains=F('value')),
[self.objs[1]],
)
def test_basic(self):
Author.objects.create(name='John', alias='xyz')
none_value = '' if connection.features.interprets_empty_strings_as_nulls else None
tests = (
(Repeat('name', 0), ''),
(Repeat('name', 2), 'JohnJohn'),
(Repeat('name', Length('alias')), 'JohnJohnJohn'),
(Repeat(Value('x'), 3), 'xxx'),
(Repeat('name', None), none_value),
(Repeat(Value(None), 4), none_value),
(Repeat('goes_by', 1), none_value),
)
for function, repeated_text in tests:
with self.subTest(function=function):
authors = Author.objects.annotate(repeated_text=function)
self.assertQuerysetEqual(authors, [repeated_text],
lambda a: a.repeated_text,
ordered=False)
def test_basic(self):
Author.objects.create(name="John", alias="xyz")
none_value = (""
if connection.features.interprets_empty_strings_as_nulls
else None)
tests = (
(Repeat("name", 0), ""),
(Repeat("name", 2), "JohnJohn"),
(Repeat("name", Length("alias")), "JohnJohnJohn"),
(Repeat(Value("x"), 3), "xxx"),
(Repeat("name", None), none_value),
(Repeat(Value(None), 4), none_value),
(Repeat("goes_by", 1), none_value),
)
for function, repeated_text in tests:
with self.subTest(function=function):
authors = Author.objects.annotate(repeated_text=function)
self.assertQuerysetEqual(authors, [repeated_text],
lambda a: a.repeated_text,
ordered=False)
def test_negative_number(self):
with self.assertRaisesMessage(
ValueError, "'number' must be greater or equal to 0."):
Repeat("name", -1)
#!/usr/bin/env python
from django.db.models.functions import Repeat
from .models import MyModel
"""
https://docs.djangoproject.com/en/dev/ref/models/database-functions/#repeat
class Repeat(expression, number, **extra)
"""
qs = MyModel.objects.annotate(name_3x=Repeat('name', 3))
for r in qs.all():
print(r.name_3x)