PayrollManagementSystem/backend/tests/unit/test_config.py

"""配置模块单元测试。

用 `_env_file=None` 绕过 backend/.env，使断言不受开发者本地配置影响。
"""

import pytest
from pydantic import ValidationError

from app.core.config import Settings

VALID_SECRET = "x" * 32


def _settings(**overrides: object) -> Settings:
    """构造一个不读取 .env 的配置实例。"""
    # _env_file=None 只禁用文件读取；显式值避免隔离测试库的环境变量影响默认值断言。
    params: dict[str, object] = {
        "_env_file": None,
        "app_secret_key": VALID_SECRET,
        "mysql_database": "payroll",
    }
    params.update(overrides)
    return Settings(**params)  # type: ignore[arg-type]


class TestSecretKey:
    """密钥强度校验。"""

    def test_缺失密钥时拒绝构造(self) -> None:
        with pytest.raises(ValidationError):
            Settings(_env_file=None)  # type: ignore[call-arg]

    @pytest.mark.parametrize("length", [0, 1, 31])
    def test_密钥短于32字符时拒绝(self, length: int) -> None:
        with pytest.raises(ValidationError):
            _settings(app_secret_key="x" * length)

    def test_密钥恰好32字符时通过(self) -> None:
        assert _settings(app_secret_key="x" * 32).app_secret_key == "x" * 32


class TestSecurityBounds:
    """安全边界：规范要求 JWT ≤120 分钟、验证码 300 秒。"""

    def test_jwt有效期超过120分钟时拒绝(self) -> None:
        with pytest.raises(ValidationError):
            _settings(jwt_expire_minutes=121)

    def test_jwt有效期为120分钟时通过(self) -> None:
        assert _settings(jwt_expire_minutes=120).jwt_expire_minutes == 120

    def test_验证码有效期超过300秒时拒绝(self) -> None:
        with pytest.raises(ValidationError):
            _settings(captcha_expire_seconds=301)

    def test_验证码有效期为300秒时通过(self) -> None:
        assert _settings(captcha_expire_seconds=300).captcha_expire_seconds == 300


class TestConnectionUrl:
    """连接 URL 构造：密码含特殊字符时不可手工拼接。"""

    def test_数据库URL使用同步驱动(self) -> None:
        """运行期与迁移共用同步连接串，不存在同步/异步两套配置。"""
        url = _settings().database_url
        assert url.drivername == "mysql+pymysql"
        assert url.database == "payroll"
        assert url.query.get("charset") == "utf8mb4"

    def test_密码含特殊字符时被原样保存于URL对象(self) -> None:
        url = _settings(mysql_password="p@ss:w/ord#1").database_url
        # URL.create 以结构化方式保存各组件，不做编码 —— 编码发生在驱动建连时，
        # 这正是手工拼接字符串会出错（如把 : 误认为端口分隔符）而它不会的原因
        assert url.password == "p@ss:w/ord#1"
        assert url.username == "payroll"
        assert url.port == 3306

    def test_渲染URL时默认隐藏密码(self) -> None:
        """异常或日志中打印 URL 时不得泄露密码。"""
        url = _settings(mysql_password="p@ss:w/ord#1").database_url
        assert "p@ss:w/ord#1" not in url.render_as_string()

    def test_Redis无密码时不拼接认证段(self) -> None:
        assert _settings(redis_password="").redis_url == "redis://127.0.0.1:6379/0"

    def test_Redis有密码时拼接认证段(self) -> None:
        url = _settings(redis_password="secret").redis_url
        assert url == "redis://:secret@127.0.0.1:6379/0"