import pytest


@pytest.fixture
def toddler(request, monkeypatch):
    """Fixture creating a toddler for a class testing it

    The test class must set the toddler class in its `toddler_cls` attribute.
    """
    test_cls = request.cls
    if not hasattr(test_cls, "toddler_cls"):
        raise RuntimeError(f"{test_cls} needs to set `toddler_cls`")

    toddler_cls = test_cls.toddler_cls

    toddler_obj = toddler_cls()
    return toddler_obj