Python Testing

Python 测试速查。当需要：(1) 运行 pytest 测试 (2) 使用 mock/patch (3) 参数化测试 (4) fixtures (5) 异步测试 (6) 覆盖率测试时使用。

Python 测试框架核心用法速查。

快速参考

pytest 基础

pytest                        # 运行所有测试
pytest -v                     # 详细输出
pytest test_module.py         # 指定文件
pytest -k "login"             # 匹配测试名
pytest -x                     # 失败时停止
pytest -n 4                   # 并行执行

测试示例

def test_addition():
    assert 1 + 1 == 2

@pytest.mark.parametrize("a,b,expected", [(1,2,3), (2,3,5)])
def test_add(a, b, expected):
    assert add(a, b) == expected

Mock

from unittest.mock import Mock, patch

mock_db = Mock()
mock_db.query.return_value = []

@patch('module.function')
def test_with_mock(mock_func):
    mock_func.return_value = 42

Fixture

@pytest.fixture
def database():
    db = Database(":memory:")
    yield db
    db.close()

def test_query(database):
    assert database.query("SELECT 1")

覆盖率

pytest --cov=myapp
pytest --cov=myapp --cov-report=html

详细参考

• pytest 详解: references/pytest.md - 完整 pytest 用法
• Mock 和 Patch: references/mocking.md - unittest.mock 详解
• Fixtures: references/fixtures.md - fixture 高级用法
• 异步测试: references/async.md - pytest-asyncio
• 覆盖率: references/coverage.md - pytest-cov 配置

常用标记

@pytest.mark.slow              # 标记慢测试
@pytest.mark.integration       # 标记集成测试
@pytest.mark.skip(reason="TODO")
@pytest.mark.skipif(sys.version_info < (3, 10))

pytest.ini 配置

[pytest]
testpaths = tests
python_files = test_*.py
markers =
    slow: marks tests as slow
    integration: integration tests
addopts = -v --tb=short

文档

• pytest: https://docs.pytest.org/
• pytest-cov: https://pytest-cov.readthedocs.io/