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88054de673
* docs: add Chinese versions docs * update --------- Co-authored-by: neo <neo.dowithless@gmail.com>
729 lines
20 KiB
Markdown
729 lines
20 KiB
Markdown
---
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name: django-tdd
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description: Django测试策略，包括pytest-django、TDD方法论、factory_boy、模拟、覆盖率以及测试Django REST Framework API。
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---
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# 使用 TDD 进行 Django 测试
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使用 pytest、factory\_boy 和 Django REST Framework 进行 Django 应用程序的测试驱动开发。
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## 何时激活
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* 编写新的 Django 应用程序时
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* 实现 Django REST Framework API 时
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* 测试 Django 模型、视图和序列化器时
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* 为 Django 项目设置测试基础设施时
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## Django 的 TDD 工作流
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### 红-绿-重构循环
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```python
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# Step 1: RED - Write failing test
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def test_user_creation():
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user = User.objects.create_user(email='test@example.com', password='testpass123')
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assert user.email == 'test@example.com'
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assert user.check_password('testpass123')
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assert not user.is_staff
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# Step 2: GREEN - Make test pass
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# Create User model or factory
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# Step 3: REFACTOR - Improve while keeping tests green
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```
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## 设置
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### pytest 配置
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```ini
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# pytest.ini
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[pytest]
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DJANGO_SETTINGS_MODULE = config.settings.test
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testpaths = tests
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python_files = test_*.py
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python_classes = Test*
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python_functions = test_*
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addopts =
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--reuse-db
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--nomigrations
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--cov=apps
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--cov-report=html
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--cov-report=term-missing
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--strict-markers
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markers =
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slow: marks tests as slow
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integration: marks tests as integration tests
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```
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### 测试设置
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```python
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# config/settings/test.py
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from .base import *
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DEBUG = True
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DATABASES = {
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'default': {
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'ENGINE': 'django.db.backends.sqlite3',
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'NAME': ':memory:',
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}
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}
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# Disable migrations for speed
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class DisableMigrations:
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def __contains__(self, item):
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return True
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def __getitem__(self, item):
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return None
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MIGRATION_MODULES = DisableMigrations()
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# Faster password hashing
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PASSWORD_HASHERS = [
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'django.contrib.auth.hashers.MD5PasswordHasher',
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]
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# Email backend
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EMAIL_BACKEND = 'django.core.mail.backends.console.EmailBackend'
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# Celery always eager
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CELERY_TASK_ALWAYS_EAGER = True
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CELERY_TASK_EAGER_PROPAGATES = True
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```
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### conftest.py
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```python
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# tests/conftest.py
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import pytest
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from django.utils import timezone
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from django.contrib.auth import get_user_model
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User = get_user_model()
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@pytest.fixture(autouse=True)
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def timezone_settings(settings):
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"""Ensure consistent timezone."""
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settings.TIME_ZONE = 'UTC'
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@pytest.fixture
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def user(db):
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"""Create a test user."""
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return User.objects.create_user(
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email='test@example.com',
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password='testpass123',
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username='testuser'
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)
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@pytest.fixture
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def admin_user(db):
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"""Create an admin user."""
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return User.objects.create_superuser(
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email='admin@example.com',
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password='adminpass123',
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username='admin'
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)
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@pytest.fixture
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def authenticated_client(client, user):
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"""Return authenticated client."""
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client.force_login(user)
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return client
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@pytest.fixture
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def api_client():
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"""Return DRF API client."""
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from rest_framework.test import APIClient
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return APIClient()
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@pytest.fixture
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def authenticated_api_client(api_client, user):
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"""Return authenticated API client."""
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api_client.force_authenticate(user=user)
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return api_client
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```
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## Factory Boy
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### 工厂设置
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```python
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# tests/factories.py
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import factory
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from factory import fuzzy
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from datetime import datetime, timedelta
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from django.contrib.auth import get_user_model
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from apps.products.models import Product, Category
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User = get_user_model()
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class UserFactory(factory.django.DjangoModelFactory):
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"""Factory for User model."""
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class Meta:
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model = User
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email = factory.Sequence(lambda n: f"user{n}@example.com")
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username = factory.Sequence(lambda n: f"user{n}")
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password = factory.PostGenerationMethodCall('set_password', 'testpass123')
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first_name = factory.Faker('first_name')
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last_name = factory.Faker('last_name')
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is_active = True
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class CategoryFactory(factory.django.DjangoModelFactory):
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"""Factory for Category model."""
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class Meta:
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model = Category
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name = factory.Faker('word')
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slug = factory.LazyAttribute(lambda obj: obj.name.lower())
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description = factory.Faker('text')
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class ProductFactory(factory.django.DjangoModelFactory):
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"""Factory for Product model."""
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class Meta:
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model = Product
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name = factory.Faker('sentence', nb_words=3)
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slug = factory.LazyAttribute(lambda obj: obj.name.lower().replace(' ', '-'))
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description = factory.Faker('text')
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price = fuzzy.FuzzyDecimal(10.00, 1000.00, 2)
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stock = fuzzy.FuzzyInteger(0, 100)
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is_active = True
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category = factory.SubFactory(CategoryFactory)
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created_by = factory.SubFactory(UserFactory)
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@factory.post_generation
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def tags(self, create, extracted, **kwargs):
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"""Add tags to product."""
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if not create:
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return
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if extracted:
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for tag in extracted:
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self.tags.add(tag)
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```
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### 使用工厂
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```python
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# tests/test_models.py
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import pytest
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from tests.factories import ProductFactory, UserFactory
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def test_product_creation():
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"""Test product creation using factory."""
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product = ProductFactory(price=100.00, stock=50)
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assert product.price == 100.00
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assert product.stock == 50
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assert product.is_active is True
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def test_product_with_tags():
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"""Test product with tags."""
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tags = [TagFactory(name='electronics'), TagFactory(name='new')]
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product = ProductFactory(tags=tags)
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assert product.tags.count() == 2
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def test_multiple_products():
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"""Test creating multiple products."""
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products = ProductFactory.create_batch(10)
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assert len(products) == 10
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```
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## 模型测试
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### 模型测试
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```python
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# tests/test_models.py
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import pytest
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from django.core.exceptions import ValidationError
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from tests.factories import UserFactory, ProductFactory
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class TestUserModel:
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"""Test User model."""
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def test_create_user(self, db):
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"""Test creating a regular user."""
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user = UserFactory(email='test@example.com')
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assert user.email == 'test@example.com'
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assert user.check_password('testpass123')
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assert not user.is_staff
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assert not user.is_superuser
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def test_create_superuser(self, db):
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"""Test creating a superuser."""
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user = UserFactory(
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email='admin@example.com',
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is_staff=True,
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is_superuser=True
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)
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assert user.is_staff
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assert user.is_superuser
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def test_user_str(self, db):
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"""Test user string representation."""
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user = UserFactory(email='test@example.com')
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assert str(user) == 'test@example.com'
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class TestProductModel:
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"""Test Product model."""
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def test_product_creation(self, db):
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"""Test creating a product."""
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product = ProductFactory()
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assert product.id is not None
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assert product.is_active is True
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assert product.created_at is not None
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def test_product_slug_generation(self, db):
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"""Test automatic slug generation."""
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product = ProductFactory(name='Test Product')
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assert product.slug == 'test-product'
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def test_product_price_validation(self, db):
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"""Test price cannot be negative."""
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product = ProductFactory(price=-10)
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with pytest.raises(ValidationError):
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product.full_clean()
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def test_product_manager_active(self, db):
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"""Test active manager method."""
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ProductFactory.create_batch(5, is_active=True)
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ProductFactory.create_batch(3, is_active=False)
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active_count = Product.objects.active().count()
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assert active_count == 5
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def test_product_stock_management(self, db):
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"""Test stock management."""
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product = ProductFactory(stock=10)
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product.reduce_stock(5)
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product.refresh_from_db()
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assert product.stock == 5
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with pytest.raises(ValueError):
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product.reduce_stock(10) # Not enough stock
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```
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## 视图测试
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### Django 视图测试
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```python
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# tests/test_views.py
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import pytest
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from django.urls import reverse
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from tests.factories import ProductFactory, UserFactory
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class TestProductViews:
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"""Test product views."""
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def test_product_list(self, client, db):
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"""Test product list view."""
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ProductFactory.create_batch(10)
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response = client.get(reverse('products:list'))
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assert response.status_code == 200
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assert len(response.context['products']) == 10
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def test_product_detail(self, client, db):
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"""Test product detail view."""
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product = ProductFactory()
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response = client.get(reverse('products:detail', kwargs={'slug': product.slug}))
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assert response.status_code == 200
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assert response.context['product'] == product
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def test_product_create_requires_login(self, client, db):
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"""Test product creation requires authentication."""
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response = client.get(reverse('products:create'))
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assert response.status_code == 302
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assert response.url.startswith('/accounts/login/')
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def test_product_create_authenticated(self, authenticated_client, db):
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"""Test product creation as authenticated user."""
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response = authenticated_client.get(reverse('products:create'))
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assert response.status_code == 200
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def test_product_create_post(self, authenticated_client, db, category):
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"""Test creating a product via POST."""
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data = {
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'name': 'Test Product',
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'description': 'A test product',
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'price': '99.99',
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'stock': 10,
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'category': category.id,
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}
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response = authenticated_client.post(reverse('products:create'), data)
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assert response.status_code == 302
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assert Product.objects.filter(name='Test Product').exists()
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```
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## DRF API 测试
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### 序列化器测试
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```python
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# tests/test_serializers.py
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import pytest
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from rest_framework.exceptions import ValidationError
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from apps.products.serializers import ProductSerializer
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from tests.factories import ProductFactory
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class TestProductSerializer:
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"""Test ProductSerializer."""
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def test_serialize_product(self, db):
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"""Test serializing a product."""
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product = ProductFactory()
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serializer = ProductSerializer(product)
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data = serializer.data
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assert data['id'] == product.id
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assert data['name'] == product.name
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assert data['price'] == str(product.price)
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def test_deserialize_product(self, db):
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"""Test deserializing product data."""
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data = {
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'name': 'Test Product',
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'description': 'Test description',
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'price': '99.99',
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'stock': 10,
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'category': 1,
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}
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serializer = ProductSerializer(data=data)
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assert serializer.is_valid()
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product = serializer.save()
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assert product.name == 'Test Product'
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assert float(product.price) == 99.99
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def test_price_validation(self, db):
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"""Test price validation."""
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data = {
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'name': 'Test Product',
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'price': '-10.00',
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'stock': 10,
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}
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serializer = ProductSerializer(data=data)
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assert not serializer.is_valid()
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assert 'price' in serializer.errors
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def test_stock_validation(self, db):
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"""Test stock cannot be negative."""
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data = {
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'name': 'Test Product',
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'price': '99.99',
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'stock': -5,
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}
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serializer = ProductSerializer(data=data)
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assert not serializer.is_valid()
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assert 'stock' in serializer.errors
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```
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### API ViewSet 测试
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```python
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# tests/test_api.py
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import pytest
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from rest_framework.test import APIClient
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from rest_framework import status
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from django.urls import reverse
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from tests.factories import ProductFactory, UserFactory
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class TestProductAPI:
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"""Test Product API endpoints."""
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@pytest.fixture
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def api_client(self):
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"""Return API client."""
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return APIClient()
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def test_list_products(self, api_client, db):
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"""Test listing products."""
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ProductFactory.create_batch(10)
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url = reverse('api:product-list')
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response = api_client.get(url)
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assert response.status_code == status.HTTP_200_OK
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assert response.data['count'] == 10
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def test_retrieve_product(self, api_client, db):
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"""Test retrieving a product."""
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product = ProductFactory()
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url = reverse('api:product-detail', kwargs={'pk': product.id})
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response = api_client.get(url)
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assert response.status_code == status.HTTP_200_OK
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assert response.data['id'] == product.id
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def test_create_product_unauthorized(self, api_client, db):
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"""Test creating product without authentication."""
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url = reverse('api:product-list')
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data = {'name': 'Test Product', 'price': '99.99'}
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response = api_client.post(url, data)
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assert response.status_code == status.HTTP_401_UNAUTHORIZED
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def test_create_product_authorized(self, authenticated_api_client, db):
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"""Test creating product as authenticated user."""
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url = reverse('api:product-list')
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data = {
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'name': 'Test Product',
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'description': 'Test',
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'price': '99.99',
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'stock': 10,
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}
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response = authenticated_api_client.post(url, data)
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assert response.status_code == status.HTTP_201_CREATED
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assert response.data['name'] == 'Test Product'
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def test_update_product(self, authenticated_api_client, db):
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"""Test updating a product."""
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product = ProductFactory(created_by=authenticated_api_client.user)
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url = reverse('api:product-detail', kwargs={'pk': product.id})
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data = {'name': 'Updated Product'}
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response = authenticated_api_client.patch(url, data)
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assert response.status_code == status.HTTP_200_OK
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assert response.data['name'] == 'Updated Product'
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def test_delete_product(self, authenticated_api_client, db):
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"""Test deleting a product."""
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product = ProductFactory(created_by=authenticated_api_client.user)
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url = reverse('api:product-detail', kwargs={'pk': product.id})
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response = authenticated_api_client.delete(url)
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assert response.status_code == status.HTTP_204_NO_CONTENT
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def test_filter_products_by_price(self, api_client, db):
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"""Test filtering products by price."""
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ProductFactory(price=50)
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ProductFactory(price=150)
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url = reverse('api:product-list')
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response = api_client.get(url, {'price_min': 100})
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assert response.status_code == status.HTTP_200_OK
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assert response.data['count'] == 1
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def test_search_products(self, api_client, db):
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"""Test searching products."""
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ProductFactory(name='Apple iPhone')
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ProductFactory(name='Samsung Galaxy')
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url = reverse('api:product-list')
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response = api_client.get(url, {'search': 'Apple'})
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assert response.status_code == status.HTTP_200_OK
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assert response.data['count'] == 1
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```
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## 模拟与打补丁
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### 模拟外部服务
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```python
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# tests/test_views.py
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from unittest.mock import patch, Mock
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import pytest
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class TestPaymentView:
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"""Test payment view with mocked payment gateway."""
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@patch('apps.payments.services.stripe')
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def test_successful_payment(self, mock_stripe, client, user, product):
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"""Test successful payment with mocked Stripe."""
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# Configure mock
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mock_stripe.Charge.create.return_value = {
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'id': 'ch_123',
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'status': 'succeeded',
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'amount': 9999,
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}
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client.force_login(user)
|
||
response = client.post(reverse('payments:process'), {
|
||
'product_id': product.id,
|
||
'token': 'tok_visa',
|
||
})
|
||
|
||
assert response.status_code == 302
|
||
mock_stripe.Charge.create.assert_called_once()
|
||
|
||
@patch('apps.payments.services.stripe')
|
||
def test_failed_payment(self, mock_stripe, client, user, product):
|
||
"""Test failed payment."""
|
||
mock_stripe.Charge.create.side_effect = Exception('Card declined')
|
||
|
||
client.force_login(user)
|
||
response = client.post(reverse('payments:process'), {
|
||
'product_id': product.id,
|
||
'token': 'tok_visa',
|
||
})
|
||
|
||
assert response.status_code == 302
|
||
assert 'error' in response.url
|
||
```
|
||
|
||
### 模拟邮件发送
|
||
|
||
```python
|
||
# tests/test_email.py
|
||
from django.core import mail
|
||
from django.test import override_settings
|
||
|
||
@override_settings(EMAIL_BACKEND='django.core.mail.backends.locmem.EmailBackend')
|
||
def test_order_confirmation_email(db, order):
|
||
"""Test order confirmation email."""
|
||
order.send_confirmation_email()
|
||
|
||
assert len(mail.outbox) == 1
|
||
assert order.user.email in mail.outbox[0].to
|
||
assert 'Order Confirmation' in mail.outbox[0].subject
|
||
```
|
||
|
||
## 集成测试
|
||
|
||
### 完整流程测试
|
||
|
||
```python
|
||
# tests/test_integration.py
|
||
import pytest
|
||
from django.urls import reverse
|
||
from tests.factories import UserFactory, ProductFactory
|
||
|
||
class TestCheckoutFlow:
|
||
"""Test complete checkout flow."""
|
||
|
||
def test_guest_to_purchase_flow(self, client, db):
|
||
"""Test complete flow from guest to purchase."""
|
||
# Step 1: Register
|
||
response = client.post(reverse('users:register'), {
|
||
'email': 'test@example.com',
|
||
'password': 'testpass123',
|
||
'password_confirm': 'testpass123',
|
||
})
|
||
assert response.status_code == 302
|
||
|
||
# Step 2: Login
|
||
response = client.post(reverse('users:login'), {
|
||
'email': 'test@example.com',
|
||
'password': 'testpass123',
|
||
})
|
||
assert response.status_code == 302
|
||
|
||
# Step 3: Browse products
|
||
product = ProductFactory(price=100)
|
||
response = client.get(reverse('products:detail', kwargs={'slug': product.slug}))
|
||
assert response.status_code == 200
|
||
|
||
# Step 4: Add to cart
|
||
response = client.post(reverse('cart:add'), {
|
||
'product_id': product.id,
|
||
'quantity': 1,
|
||
})
|
||
assert response.status_code == 302
|
||
|
||
# Step 5: Checkout
|
||
response = client.get(reverse('checkout:review'))
|
||
assert response.status_code == 200
|
||
assert product.name in response.content.decode()
|
||
|
||
# Step 6: Complete purchase
|
||
with patch('apps.checkout.services.process_payment') as mock_payment:
|
||
mock_payment.return_value = True
|
||
response = client.post(reverse('checkout:complete'))
|
||
|
||
assert response.status_code == 302
|
||
assert Order.objects.filter(user__email='test@example.com').exists()
|
||
```
|
||
|
||
## 测试最佳实践
|
||
|
||
### 应该做
|
||
|
||
* **使用工厂**：而不是手动创建对象
|
||
* **每个测试一个断言**：保持测试聚焦
|
||
* **描述性测试名称**：`test_user_cannot_delete_others_post`
|
||
* **测试边界情况**：空输入、None 值、边界条件
|
||
* **模拟外部服务**：不要依赖外部 API
|
||
* **使用夹具**：消除重复
|
||
* **测试权限**：确保授权有效
|
||
* **保持测试快速**：使用 `--reuse-db` 和 `--nomigrations`
|
||
|
||
### 不应该做
|
||
|
||
* **不要测试 Django 内部**：相信 Django 能正常工作
|
||
* **不要测试第三方代码**：相信库能正常工作
|
||
* **不要忽略失败的测试**：所有测试必须通过
|
||
* **不要让测试产生依赖**：测试应该能以任何顺序运行
|
||
* **不要过度模拟**：只模拟外部依赖
|
||
* **不要测试私有方法**：测试公共接口
|
||
* **不要使用生产数据库**：始终使用测试数据库
|
||
|
||
## 覆盖率
|
||
|
||
### 覆盖率配置
|
||
|
||
```bash
|
||
# Run tests with coverage
|
||
pytest --cov=apps --cov-report=html --cov-report=term-missing
|
||
|
||
# Generate HTML report
|
||
open htmlcov/index.html
|
||
```
|
||
|
||
### 覆盖率目标
|
||
|
||
| 组件 | 目标覆盖率 |
|
||
|-----------|-----------------|
|
||
| 模型 | 90%+ |
|
||
| 序列化器 | 85%+ |
|
||
| 视图 | 80%+ |
|
||
| 服务 | 90%+ |
|
||
| 工具 | 80%+ |
|
||
| 总体 | 80%+ |
|
||
|
||
## 快速参考
|
||
|
||
| 模式 | 用途 |
|
||
|---------|-------|
|
||
| `@pytest.mark.django_db` | 启用数据库访问 |
|
||
| `client` | Django 测试客户端 |
|
||
| `api_client` | DRF API 客户端 |
|
||
| `factory.create_batch(n)` | 创建多个对象 |
|
||
| `patch('module.function')` | 模拟外部依赖 |
|
||
| `override_settings` | 临时更改设置 |
|
||
| `force_authenticate()` | 在测试中绕过身份验证 |
|
||
| `assertRedirects` | 检查重定向 |
|
||
| `assertTemplateUsed` | 验证模板使用 |
|
||
| `mail.outbox` | 检查已发送的邮件 |
|
||
|
||
记住：测试即文档。好的测试解释了你的代码应如何工作。保持测试简单、可读和可维护。
|