django/tests/postgres_tests/test_trigram.py

101 lines
3.5 KiB
Python

from django.test import modify_settings
from . import PostgreSQLTestCase
from .models import CharFieldModel, TextFieldModel
try:
from django.contrib.postgres.search import (
TrigramDistance, TrigramSimilarity, TrigramWordDistance,
TrigramWordSimilarity,
)
except ImportError:
pass
@modify_settings(INSTALLED_APPS={'append': 'django.contrib.postgres'})
class TrigramTest(PostgreSQLTestCase):
Model = CharFieldModel
@classmethod
def setUpTestData(cls):
cls.Model.objects.bulk_create([
cls.Model(field='Matthew'),
cls.Model(field='Cat sat on mat.'),
cls.Model(field='Dog sat on rug.'),
])
def test_trigram_search(self):
self.assertQuerysetEqual(
self.Model.objects.filter(field__trigram_similar='Mathew'),
['Matthew'],
transform=lambda instance: instance.field,
)
def test_trigram_word_search(self):
obj = self.Model.objects.create(
field='Gumby rides on the path of Middlesbrough',
)
self.assertSequenceEqual(
self.Model.objects.filter(field__trigram_word_similar='Middlesborough'),
[obj],
)
def test_trigram_similarity(self):
search = 'Bat sat on cat.'
# Round result of similarity because PostgreSQL 12+ uses greater
# precision.
self.assertQuerysetEqual(
self.Model.objects.filter(
field__trigram_similar=search,
).annotate(similarity=TrigramSimilarity('field', search)).order_by('-similarity'),
[('Cat sat on mat.', 0.625), ('Dog sat on rug.', 0.333333)],
transform=lambda instance: (instance.field, round(instance.similarity, 6)),
ordered=True,
)
def test_trigram_word_similarity(self):
search = 'mat'
self.assertSequenceEqual(
self.Model.objects.filter(
field__trigram_word_similar=search,
).annotate(
word_similarity=TrigramWordSimilarity(search, 'field'),
).values('field', 'word_similarity').order_by('-word_similarity'),
[
{'field': 'Cat sat on mat.', 'word_similarity': 1.0},
{'field': 'Matthew', 'word_similarity': 0.75},
],
)
def test_trigram_similarity_alternate(self):
# Round result of distance because PostgreSQL 12+ uses greater
# precision.
self.assertQuerysetEqual(
self.Model.objects.annotate(
distance=TrigramDistance('field', 'Bat sat on cat.'),
).filter(distance__lte=0.7).order_by('distance'),
[('Cat sat on mat.', 0.375), ('Dog sat on rug.', 0.666667)],
transform=lambda instance: (instance.field, round(instance.distance, 6)),
ordered=True,
)
def test_trigram_word_similarity_alternate(self):
self.assertSequenceEqual(
self.Model.objects.annotate(
word_distance=TrigramWordDistance('mat', 'field'),
).filter(
word_distance__lte=0.7,
).values('field', 'word_distance').order_by('word_distance'),
[
{'field': 'Cat sat on mat.', 'word_distance': 0},
{'field': 'Matthew', 'word_distance': 0.25},
],
)
class TrigramTextFieldTest(TrigramTest):
"""
TextField has the same behavior as CharField regarding trigram lookups.
"""
Model = TextFieldModel