python config_error ai_generated true

ScopeMismatch: You tried to access the function scoped fixture monkeypatch with a session scoped request object, involved factories

ID: python/pytest-monkeypatch-scope-session

Also available as: JSON · Markdown · 中文
80%Fix Rate
88%Confidence
0Evidence
2024-04-26First Seen

Version Compatibility

VersionStatusIntroducedDeprecatedNotes
7.x active — — —
8.x active — — —

Root Cause

A session-scoped fixture requested monkeypatch (which is function-scoped), violating pytest's scope ordering rules.

generic

中文

会话作用域的 fixture 请求了 monkeypatch（函数作用域），违反了 pytest 的作用域排序规则。

Workarounds

  1. 95% success 
    @pytest.fixture(scope="session")
def config(): return {"url": "http://x"}

@pytest.fixture
def patched(config, monkeypatch):
    monkeypatch.setitem(config, "url", "http://test")
    return config
  2. 90% success 
    @pytest.fixture(scope="session")
def patched():
    with pytest.MonkeyPatch.context() as mp:
        mp.setenv("X", "1")
        yield

Dead Ends

Common approaches that don't work:

  1. 60% fail

    May break expensive setup assumptions and hides the real scope design issue.

  2. 90% fail

    Does not change scope mismatch behavior.

  3. 85% fail

    Markers do not alter fixture scope rules.