Function test_set_caster_protocol

tests/test_stl.py:692–735

(doc)

def test_set_caster_protocol(doc):
    from collections.abc import Set

    # Implements the Set protocol without explicitly inheriting from collections.abc.Set.
    class BareSetLike:
        def __init__(self, *args):
            self.data = set(args)

        def __len__(self):
            return len(self.data)

        def __contains__(self, item):
            return item in self.data

        def __iter__(self):
            yield from self.data

    # Implements the Set protocol by reusing BareSetLike's implementation.
    # Additionally, inherits from collections.abc.Set.
    class FormalSetLike(BareSetLike, Set):
        pass

    # convert mode
    assert (
        doc(m.roundtrip_std_set_int)
        == "roundtrip_std_set_int(arg0: collections.abc.Set[typing.SupportsInt | typing.SupportsIndex]) -> set[int]"
    )
    assert m.roundtrip_std_set_int({1, 2, 3}) == {1, 2, 3}
    assert m.roundtrip_std_set_int(FormalSetLike(1, 2, 3)) == {1, 2, 3}
    assert m.roundtrip_std_set_int(set()) == set()
    assert m.roundtrip_std_set_int(FormalSetLike()) == set()
    with pytest.raises(TypeError):
        m.roundtrip_std_set_int(BareSetLike(1, 2, 3))
    # noconvert mode
    assert (
        doc(m.roundtrip_std_set_int_noconvert)
        == "roundtrip_std_set_int_noconvert(s: set[int]) -> set[int]"
    )
    assert m.roundtrip_std_set_int_noconvert({1, 2, 3}) == {1, 2, 3}
    assert m.roundtrip_std_set_int_noconvert(set()) == set()
    with pytest.raises(TypeError):
        m.roundtrip_std_set_int_noconvert(FormalSetLike(1, 2, 3))
    with pytest.raises(TypeError):
        m.roundtrip_std_set_int_noconvert(BareSetLike(1, 2, 3))