python config_error ai_generated true

ScopeMismatch: 你尝试用 session 作用域的请求对象访问 function 作用域的 fixture 'tmp_path'

ScopeMismatch: You tried to access the function scoped fixture 'tmp_path' with a session scoped request object

ID: python/pytest-scope-mismatch-session-function

其他格式: JSON · Markdown 中文 · English

80%修复率

88%置信度

0证据数

2024-05-22首次发现

版本兼容性

版本	状态	引入	弃用	备注
7.x	active	—	—	—
8.x	active	—	—	—

根因分析

较高作用域的 fixture（session/module）依赖较低作用域的 fixture（function），pytest 禁止此行为，因为低作用域 fixture 需要为每个测试重新创建。

English

A higher-scoped fixture (session/module) depends on a lower-scoped fixture (function), which pytest forbids because the lower-scoped fixture would need to be recreated per test.

generic

解决方案

92% 成功率

# Instead of session-scoped fixture depending on tmp_path:
@pytest.fixture
def db(tmp_path):
    ...

@pytest.fixture(scope="session")
def db_session():
    import tempfile
    with tempfile.TemporaryDirectory() as d:
        yield make_db(d)

75% 成功率

@pytest.fixture(scope="session")
def heavy(request):
    def get_tmp():
        return request.getfixturevalue("tmp_path")
    yield get_tmp

无效尝试

常见但无效的做法:

98% 失败
The error is raised by pytest during fixture resolution before the body runs; catching it inside the fixture never executes.
90% 失败
autouse changes when fixtures are requested, not their scope, so the ScopeMismatch persists.
95% 失败
No such option exists; pytest ignores unknown ini keys and the error remains.