| from django.db.models import F, IntegerField |
| from django.db.models.functions import Chr, Left, Ord |
| from django.test import TestCase |
| from django.test.utils import register_lookup |
|
|
| from ..models import Author |
|
|
|
|
| class ChrTests(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.rhonda = Author.objects.create(name="Rhonda") |
|
|
| def test_basic(self): |
| authors = Author.objects.annotate(first_initial=Left("name", 1)) |
| self.assertCountEqual(authors.filter(first_initial=Chr(ord("J"))), [self.john]) |
| self.assertCountEqual( |
| authors.exclude(first_initial=Chr(ord("J"))), [self.elena, self.rhonda] |
| ) |
|
|
| def test_non_ascii(self): |
| authors = Author.objects.annotate(first_initial=Left("name", 1)) |
| self.assertCountEqual(authors.filter(first_initial=Chr(ord("É"))), [self.elena]) |
| self.assertCountEqual( |
| authors.exclude(first_initial=Chr(ord("É"))), [self.john, self.rhonda] |
| ) |
|
|
| def test_transform(self): |
| with register_lookup(IntegerField, Chr): |
| authors = Author.objects.annotate(name_code_point=Ord("name")) |
| self.assertCountEqual( |
| authors.filter(name_code_point__chr=Chr(ord("J"))), [self.john] |
| ) |
| self.assertCountEqual( |
| authors.exclude(name_code_point__chr=Chr(ord("J"))), |
| [self.elena, self.rhonda], |
| ) |
|
|
| def test_annotate(self): |
| authors = Author.objects.annotate( |
| first_initial=Left("name", 1), |
| initial_chr=Chr(ord("J")), |
| ) |
| self.assertSequenceEqual( |
| authors.filter(first_initial=F("initial_chr")), |
| [self.john], |
| ) |
|
|
