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
51
52
53
54
55
56
57
58
|
import datetime
from unittest import mock
from django.db import connections
from django.db.models.sql.compiler import cursor_iter
from django.test import TestCase
from .models import Article
class QuerySetIteratorTests(TestCase):
itersize_index_in_mock_args = 3
@classmethod
def setUpTestData(cls):
Article.objects.create(name="Article 1", created=datetime.datetime.now())
Article.objects.create(name="Article 2", created=datetime.datetime.now())
def test_iterator_invalid_chunk_size(self):
for size in (0, -1):
with self.subTest(size=size):
with self.assertRaisesMessage(
ValueError, "Chunk size must be strictly positive."
):
Article.objects.iterator(chunk_size=size)
def test_default_iterator_chunk_size(self):
qs = Article.objects.iterator()
with mock.patch(
"django.db.models.sql.compiler.cursor_iter", side_effect=cursor_iter
) as cursor_iter_mock:
next(qs)
self.assertEqual(cursor_iter_mock.call_count, 1)
mock_args, _mock_kwargs = cursor_iter_mock.call_args
self.assertEqual(mock_args[self.itersize_index_in_mock_args], 2000)
def test_iterator_chunk_size(self):
batch_size = 3
qs = Article.objects.iterator(chunk_size=batch_size)
with mock.patch(
"django.db.models.sql.compiler.cursor_iter", side_effect=cursor_iter
) as cursor_iter_mock:
next(qs)
self.assertEqual(cursor_iter_mock.call_count, 1)
mock_args, _mock_kwargs = cursor_iter_mock.call_args
self.assertEqual(mock_args[self.itersize_index_in_mock_args], batch_size)
def test_no_chunked_reads(self):
"""
If the database backend doesn't support chunked reads, then the
result of SQLCompiler.execute_sql() is a list.
"""
qs = Article.objects.all()
compiler = qs.query.get_compiler(using=qs.db)
features = connections[qs.db].features
with mock.patch.object(features, "can_use_chunked_reads", False):
result = compiler.execute_sql(chunked_fetch=True)
self.assertIsInstance(result, list)
|
