django/tests/db_functions/text/test_concat.py

92 lines
3.5 KiB
Python

from unittest import skipUnless
from django.db import connection
from django.db.models import CharField, TextField
from django.db.models import Value as V
from django.db.models.functions import Concat, ConcatPair, Upper
from django.test import TestCase
from django.utils import timezone
from ..models import Article, Author
lorem_ipsum = """
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod
tempor incididunt ut labore et dolore magna aliqua."""
class ConcatTests(TestCase):
def test_basic(self):
Author.objects.create(name="Jayden")
Author.objects.create(name="John Smith", alias="smithj", goes_by="John")
Author.objects.create(name="Margaret", goes_by="Maggie")
Author.objects.create(name="Rhonda", alias="adnohR")
authors = Author.objects.annotate(joined=Concat("alias", "goes_by"))
self.assertQuerySetEqual(
authors.order_by("name"),
[
"",
"smithjJohn",
"Maggie",
"adnohR",
],
lambda a: a.joined,
)
def test_gt_two_expressions(self):
with self.assertRaisesMessage(
ValueError, "Concat must take at least two expressions"
):
Author.objects.annotate(joined=Concat("alias"))
def test_many(self):
Author.objects.create(name="Jayden")
Author.objects.create(name="John Smith", alias="smithj", goes_by="John")
Author.objects.create(name="Margaret", goes_by="Maggie")
Author.objects.create(name="Rhonda", alias="adnohR")
authors = Author.objects.annotate(
joined=Concat("name", V(" ("), "goes_by", V(")"), output_field=CharField()),
)
self.assertQuerySetEqual(
authors.order_by("name"),
[
"Jayden ()",
"John Smith (John)",
"Margaret (Maggie)",
"Rhonda ()",
],
lambda a: a.joined,
)
def test_mixed_char_text(self):
Article.objects.create(
title="The Title", text=lorem_ipsum, written=timezone.now()
)
article = Article.objects.annotate(
title_text=Concat("title", V(" - "), "text", output_field=TextField()),
).get(title="The Title")
self.assertEqual(article.title + " - " + article.text, article.title_text)
# Wrap the concat in something else to ensure that text is returned
# rather than bytes.
article = Article.objects.annotate(
title_text=Upper(
Concat("title", V(" - "), "text", output_field=TextField())
),
).get(title="The Title")
expected = article.title + " - " + article.text
self.assertEqual(expected.upper(), article.title_text)
@skipUnless(connection.vendor == "sqlite", "sqlite specific implementation detail.")
def test_coalesce_idempotent(self):
pair = ConcatPair(V("a"), V("b"))
# Check nodes counts
self.assertEqual(len(list(pair.flatten())), 3)
self.assertEqual(
len(list(pair.coalesce().flatten())), 7
) # + 2 Coalesce + 2 Value()
self.assertEqual(len(list(pair.flatten())), 3)
def test_sql_generation_idempotency(self):
qs = Article.objects.annotate(description=Concat("title", V(": "), "summary"))
# Multiple compilations should not alter the generated query.
self.assertEqual(str(qs.query), str(qs.all().query))