1# https://github.com/pytest-dev/pytest/blob/main/testing/logging/test_fixture.py
2# testing/logging/test_fixture.py
3
4logger = logging.getLogger(__name__)
5sublogger = logging.getLogger(__name__ + ".baz")
6
7# fixture の使い方の雰囲気をつかむのに Good
8@pytest.fixture(autouse=True)
9def cleanup_disabled_logging() -> Iterator[None]:
10    """Simple fixture that ensures that a test doesn't disable logging.
11
12    This is necessary because ``logging.disable()`` is global, so a test disabling logging
13    and not cleaning up after will break every test that runs after it.
14
15    This behavior was moved to a fixture so that logging will be un-disabled even if the test fails an assertion.
16    """
17    yield
18    logging.disable(logging.NOTSET)
19
20# 特定のログレベルのログのみが記録されたかを検証するテストコード
21# caplog の使い方を知れるだけでなく、Given-When-Then の構造をつかむのにもよいサンプル
22# 一例としてコメントでGiven-When-Thenを添える
23def test_change_level(caplog: pytest.LogCaptureFixture) -> None:
24    # Given
25    caplog.set_level(logging.INFO)
26
27    # When
28    logger.debug("handler DEBUG level")
29    logger.info("handler INFO level")
30    caplog.set_level(logging.CRITICAL, logger=sublogger.name)
31    sublogger.warning("logger WARNING level")
32    sublogger.critical("logger CRITICAL level")
33
34    # THEN
35    assert "DEBUG" not in caplog.text
36    assert "INFO" in caplog.text
37    assert "WARNING" not in caplog.text
38    assert "CRITICAL" in caplog.text

1ファイルの読み書きのテストコードを書きたいです。
2pytest ではどのように書くのがよいか理解するため、
3以下の pytest のリポジトリから参考になるテストファイルを教えてください。
4https://github.com/pytest-dev/pytest/tree/main/testing

1# https://github.com/encode/django-rest-framework/blob/main/tests/test_validators.py
2# tests/test_validators.py
3
4class TestUniquenessValidation(TestCase):
5    def setUp(self):
6        self.instance = UniquenessModel.objects.create(username='existing')
7
8    # テストケースの命名と構造に注目する
9    # テストしたい対象の状態で命名し、
10    # 期待値 → 実際に得られたオブジェクトを比較してアサーションとする構造を読み取りたい
11    def test_is_not_unique(self):
12        # Given
13        data = {'username': 'existing'}
14        # When
15        serializer = UniquenessSerializer(data=data)
16        # Then
17        assert not serializer.is_valid()
18        assert serializer.errors == {'username': ['uniqueness model with this username already exists.']}
19
20    def test_relation_is_not_unique(self):
21        RelatedModel.objects.create(user=self.instance)
22        data = {'user': self.instance.pk}
23        serializer = RelatedModelUserSerializer(data=data)
24        assert not serializer.is_valid()
25        assert serializer.errors == {'user': ['related model with this user already exists.']}
26
27    def test_is_unique(self):
28        data = {'username': 'other'}
29        serializer = UniquenessSerializer(data=data)
30        assert serializer.is_valid()
31        assert serializer.validated_data == {'username': 'other'}

1class TestTocNodeTreeGenerator:
2    """ ヘッダBlockから目次構造のツリーをつくれるか検証 """
3
4    # ヘッダから対応する目次構造のツリーをつくれるか
5    @pytest.mark.parametrize(
6        ('header_text_list', 'expected_list'),
7        [
8            (
9                ['# 概要'],
10                [TocNode(depth=1, text='概要', children=[])]
11            ),
12            (
13                ['# 概要', '## ゴール'],
14                [TocNode(depth=1, text='概要', children=[
15                    TocNode(depth=2, text='ゴール', children=[])])
16                 ]
17            ),
18            (
19                ['# 概要', '## 用語整理', '### Pythonとは', '#### 補足: Pythonの由来', '### たのしいPython'],
20                [TocNode(depth=1, text='概要', children=[
21                    TocNode(depth=2, text='用語整理', children=[
22                        TocNode(depth=3, text='Pythonとは', children=[
23                            TocNode(depth=4, text='補足: Pythonの由来', children=[])
24                        ])
25                        , TocNode(depth=3, text='たのしいPython', children=[])
26                    ])
27                ])]
28            ),
29            (
30                ['# 目次の`テスト`', '## [link](url)'],
31                [TocNode(depth=1, text='目次のテスト', children=[
32                    TocNode(depth=2, text='link', children=[])
33                ])]
34            )
35        ],
36        ids=['single element', 'single child', 'multiple child', 'contains inline element']
37    )
38    def test_generate_single_tree(self, header_text_list: list[str], expected_list: list[TocNode]):
39        # GIVEN
40        sut = TocNodeTreeGenerator()
41        block_list = MarkdownParser().parse(header_text_list).content
42        header_list = [block for block in block_list if isinstance(block, HeadingBlock)]
43
44        # WHEN
45        actual_list = sut.generate(header_list)
46        # THEN
47        for actual, expected in zip(actual_list, expected_list):
48            assert actual == expected

1# https://github.com/django/django/blob/main/tests/admin_views/tests.py
2# tests/admin_views/tests.py
3
4@override_settings(
5    MAILERS={"default": {"BACKEND": "django.core.mail.backends.locmem.EmailBackend"}}
6)
7class AdminViewBasicTest(AdminViewBasicTestCase):
8    # 振る舞いのみをテストしているので、HTTP リクエストを送り、ステータスコードを確認するのみ
9    def test_trailing_slash_required(self):
10        """
11        If you leave off the trailing slash, app should redirect and add it.
12        """
13        add_url = reverse("admin:admin_views_article_add")
14        response = self.client.get(add_url[:-1])
15        self.assertRedirects(response, add_url, status_code=301)
16
17    def test_basic_add_GET(self):
18        """
19        A smoke test to ensure GET on the add_view works.
20        """
21        response = self.client.get(reverse("admin:admin_views_section_add"))
22        self.assertIsInstance(response, TemplateResponse)
23        self.assertEqual(response.status_code, 200)

1@override_settings(ROOT_URLCONF="admin_views.urls")
2class SaveAsTests(TestCase):
3    @classmethod
4    def setUpTestData(cls):
5        cls.superuser = User.objects.create_superuser(
6            username="super", password="secret", email="super@example.com"
7        )
8        cls.per1 = Person.objects.create(name="John Mauchly", gender=1, alive=True)
9
10    def setUp(self):
11        self.client.force_login(self.superuser)
12
13    # 複製で保存したいとき、元データを残して新しいデータを登録するという振る舞いを検証
14    def test_save_as_duplication(self):
15        """'save as' creates a new person"""
16        post_data = {"_saveasnew": "", "name": "John M", "gender": 1, "age": 42}
17        response = self.client.post(
18            reverse("admin:admin_views_person_change", args=(self.per1.pk,)), post_data
19        )
20        self.assertEqual(len(Person.objects.filter(name="John M")), 1)
21        self.assertEqual(len(Person.objects.filter(id=self.per1.pk)), 1)
22        new_person = Person.objects.latest("id")
23        self.assertRedirects(
24            response, reverse("admin:admin_views_person_change", args=(new_person.pk,))
25        )
26
27    # 保存後の画面遷移という振る舞いを検証
28    def test_save_as_continue_false(self):
29        """
30        Saving a new object using "Save as new" redirects to the changelist
31        instead of the change view when ModelAdmin.save_as_continue=False.
32        """
33        post_data = {"_saveasnew": "", "name": "John M", "gender": 1, "age": 42}
34        url = reverse(
35            "admin:admin_views_person_change",
36            args=(self.per1.pk,),
37            current_app=site2.name,
38        )
39        response = self.client.post(url, post_data)
40        self.assertEqual(len(Person.objects.filter(name="John M")), 1)
41        self.assertEqual(len(Person.objects.filter(id=self.per1.pk)), 1)
42        self.assertRedirects(
43            response,
44            reverse("admin:admin_views_person_changelist", current_app=site2.name),
45        )
46
47    # バリデーションエラーが画面に表示されるかという振る舞いを検証
48    def test_save_as_new_with_validation_errors(self):
49        """
50        When you click "Save as new" and have a validation error,
51        you only see the "Save as new" button and not the other save buttons,
52        and that only the "Save as" button is visible.
53        """
54        response = self.client.post(
55            reverse("admin:admin_views_person_change", args=(self.per1.pk,)),
56            {
57                "_saveasnew": "",
58                "gender": "invalid",
59                "_addanother": "fail",
60            },
61        )
62        self.assertContains(response, "Please correct the errors below.")
63        self.assertFalse(response.context["show_save_and_add_another"])
64        self.assertFalse(response.context["show_save_and_continue"])
65        self.assertTrue(response.context["show_save_as_new"])

1# https://github.com/awesto/django-shop/blob/master/tests/test_checkout.py
2# tests/test_checkout.py
3
4# HTTP リクエストを送り、結果としてデータベースがどう変動したかをもって振る舞いを観測するテスト
5@pytest.mark.django_db
6def test_add_shipping_address(registered_customer, api_rf, empty_cart, address_data):
7    data = dict(shipping_address=address_data, active_priority='add')
8    request = api_rf.put('/shop/api/checkout/upload', data, format='json')
9    request.customer = registered_customer
10    request.user = registered_customer.user
11    assert registered_customer.shippingaddress_set.count() == 0
12    assert registered_customer.billingaddress_set.count() == 0
13
14    # データ更新
15    response = CheckoutViewSet.as_view({'put': 'upload'})(request)
16    assert response.status_code == 200
17    assert response.data['shipping_address_form']['name'] == address_data['name']
18    label = "1. John Doe – 31 Orwell Road – L41RG Liverpool – United Kingdom"
19    assert response.data['shipping_address_form']['siblings_summary'][0]['label'] == label
20    registered_customer.refresh_from_db()
21    assert registered_customer.billingaddress_set.count() == 0
22    shipping_address = registered_customer.shippingaddress_set.first()
23
24    # アサーション
25    assert shipping_address
26    assert shipping_address.name == address_data['name']
27    assert shipping_address.address1 == address_data['address1']
28    assert shipping_address.zip_code == address_data['zip_code']
29    assert shipping_address.city == address_data['city']
30    assert shipping_address.country == address_data['country']