Function limit_loader

tests/conftest.py:100–127

Patch pkgutil.get_loader to give loader without get_filename or archive. This provides for tests where a system has custom loaders, e.g. Google App Engine's HardenedModulesHook, which have neither the `get_filename` method nor the `archive` attribute. This fixture will run the test

(request, monkeypatch)

@pytest.fixture(params=(True, False))
def limit_loader(request, monkeypatch):
    """Patch pkgutil.get_loader to give loader without get_filename or archive.

    This provides for tests where a system has custom loaders, e.g. Google App
    Engine's HardenedModulesHook, which have neither the `get_filename` method
    nor the `archive` attribute.

    This fixture will run the testcase twice, once with and once without the
    limitation/mock.
    """
    if not request.param:
        return

    class LimitedLoader:
        def __init__(self, loader):
            self.loader = loader

        def __getattr__(self, name):
            if name in {"archive", "get_filename"}:
                raise AttributeError(f"Mocking a loader which does not have {name!r}.")
            return getattr(self.loader, name)

    old_get_loader = pkgutil.get_loader

    def get_loader(*args, **kwargs):
        return LimitedLoader(old_get_loader(*args, **kwargs))

    monkeypatch.setattr(pkgutil, "get_loader", get_loader)


@pytest.fixture