def test_init_factory_basic():
    """Tests py::init_factory() wrapper around various ways of returning the object"""

    cstats = [
        ConstructorStats.get(c)
        for c in [m.TestFactory1, m.TestFactory2, m.TestFactory3]
    ]
    cstats[0].alive()  # force gc
    n_inst = ConstructorStats.detail_reg_inst()

    x1 = m.TestFactory1(tag.unique_ptr, 3)
    assert x1.value == "3"
    y1 = m.TestFactory1(tag.pointer)
    assert y1.value == "(empty)"
    z1 = m.TestFactory1("hi!")
    assert z1.value == "hi!"

    assert ConstructorStats.detail_reg_inst() == n_inst + 3

    x2 = m.TestFactory2(tag.move)
    assert x2.value == "(empty2)"
    y2 = m.TestFactory2(tag.pointer, 7)
    assert y2.value == "7"
    z2 = m.TestFactory2(tag.unique_ptr, "hi again")
    assert z2.value == "hi again"

    assert ConstructorStats.detail_reg_inst() == n_inst + 6

    x3 = m.TestFactory3(tag.shared_ptr)
    assert x3.value == "(empty3)"
    y3 = m.TestFactory3(tag.pointer, 42)
    assert y3.value == "42"
    z3 = m.TestFactory3("bye")
    assert z3.value == "bye"

    for null_ptr_kind in [
            tag.null_ptr, tag.null_unique_ptr, tag.null_shared_ptr
    ]:
        with pytest.raises(TypeError) as excinfo:
            m.TestFactory3(null_ptr_kind)
        assert (str(excinfo.value) ==
                "pybind11::init(): factory function returned nullptr")

    assert [i.alive() for i in cstats] == [3, 3, 3]
    assert ConstructorStats.detail_reg_inst() == n_inst + 9

    del x1, y2, y3, z3
    assert [i.alive() for i in cstats] == [2, 2, 1]
    assert ConstructorStats.detail_reg_inst() == n_inst + 5
    del x2, x3, y1, z1, z2
    assert [i.alive() for i in cstats] == [0, 0, 0]
    assert ConstructorStats.detail_reg_inst() == n_inst

    assert [i.values() for i in cstats] == [
        ["3", "hi!"],
        ["7", "hi again"],
        ["42", "bye"],
    ]
    assert [i.default_constructions for i in cstats] == [1, 1, 1]
def test_init_factory_signature(msg):
    with pytest.raises(TypeError) as excinfo:
        m.TestFactory1("invalid", "constructor", "arguments")
    assert (msg(excinfo.value) == """
        __init__(): incompatible constructor arguments. The following argument types are supported:
            1. m.factory_constructors.TestFactory1(arg0: m.factory_constructors.tag.unique_ptr_tag, arg1: int)
            2. m.factory_constructors.TestFactory1(arg0: str)
            3. m.factory_constructors.TestFactory1(arg0: m.factory_constructors.tag.pointer_tag)
            4. m.factory_constructors.TestFactory1(arg0: handle, arg1: int, arg2: handle)

        Invoked with: 'invalid', 'constructor', 'arguments'
    """

            # noqa: E501 line too long
            )

    assert (msg(m.TestFactory1.__init__.__doc__) == """
        __init__(*args, **kwargs)
        Overloaded function.

        1. __init__(self: m.factory_constructors.TestFactory1, arg0: m.factory_constructors.tag.unique_ptr_tag, arg1: int) -> None

        2. __init__(self: m.factory_constructors.TestFactory1, arg0: str) -> None

        3. __init__(self: m.factory_constructors.TestFactory1, arg0: m.factory_constructors.tag.pointer_tag) -> None

        4. __init__(self: m.factory_constructors.TestFactory1, arg0: handle, arg1: int, arg2: handle) -> None
    """

            # noqa: E501 line too long
            )