ext/pybind11/tests/test_pytypes.py

import pytest
import sys

from pybind11_tests import pytypes as m
from pybind11_tests import debug_enabled


def test_list(capture, doc):
    with capture:
        l = m.get_list()
        assert l == ["overwritten"]

        l.append("value2")
        m.print_list(l)
    assert capture.unordered == """
        Entry at position 0: value
        list item 0: overwritten
        list item 1: value2
    """

    assert doc(m.get_list) == "get_list() -> list"
    assert doc(m.print_list) == "print_list(arg0: list) -> None"


def test_set(capture, doc):
    s = m.get_set()
    assert s == {"key1", "key2", "key3"}

    with capture:
        s.add("key4")
        m.print_set(s)
    assert capture.unordered == """
        key: key1
        key: key2
        key: key3
        key: key4
    """

    assert doc(m.get_list) == "get_list() -> list"
    assert doc(m.print_list) == "print_list(arg0: list) -> None"


def test_dict(capture, doc):
    d = m.get_dict()
    assert d == {"key": "value"}

    with capture:
        d["key2"] = "value2"
        m.print_dict(d)
    assert capture.unordered == """
        key: key, value=value
        key: key2, value=value2
    """

    assert doc(m.get_dict) == "get_dict() -> dict"
    assert doc(m.print_dict) == "print_dict(arg0: dict) -> None"

    assert m.dict_keyword_constructor() == {"x": 1, "y": 2, "z": 3}


def test_str(doc):
    assert m.str_from_string().encode().decode() == "baz"
    assert m.str_from_bytes().encode().decode() == "boo"

    assert doc(m.str_from_bytes) == "str_from_bytes() -> str"

    class A(object):
        def __str__(self):
            return "this is a str"

        def __repr__(self):
            return "this is a repr"

    assert m.str_from_object(A()) == "this is a str"
    assert m.repr_from_object(A()) == "this is a repr"

    s1, s2 = m.str_format()
    assert s1 == "1 + 2 = 3"
    assert s1 == s2


def test_bytes(doc):
    assert m.bytes_from_string().decode() == "foo"
    assert m.bytes_from_str().decode() == "bar"

    assert doc(m.bytes_from_str) == "bytes_from_str() -> {}".format(
        "bytes" if sys.version_info[0] == 3 else "str"
    )


def test_capsule(capture):
    pytest.gc_collect()
    with capture:
        a = m.return_capsule_with_destructor()
        del a
        pytest.gc_collect()
    assert capture.unordered == """
        creating capsule
        destructing capsule
    """

    with capture:
        a = m.return_capsule_with_destructor_2()
        del a
        pytest.gc_collect()
    assert capture.unordered == """
        creating capsule
        destructing capsule: 1234
    """

    with capture:
        a = m.return_capsule_with_name_and_destructor()
        del a
        pytest.gc_collect()
    assert capture.unordered == """
        created capsule (1234, 'pointer type description')
        destructing capsule (1234, 'pointer type description')
    """


def test_accessors():
    class SubTestObject:
        attr_obj = 1
        attr_char = 2

    class TestObject:
        basic_attr = 1
        begin_end = [1, 2, 3]
        d = {"operator[object]": 1, "operator[char *]": 2}
        sub = SubTestObject()

        def func(self, x, *args):
            return self.basic_attr + x + sum(args)

    d = m.accessor_api(TestObject())
    assert d["basic_attr"] == 1
    assert d["begin_end"] == [1, 2, 3]
    assert d["operator[object]"] == 1
    assert d["operator[char *]"] == 2
    assert d["attr(object)"] == 1
    assert d["attr(char *)"] == 2
    assert d["missing_attr_ptr"] == "raised"
    assert d["missing_attr_chain"] == "raised"
    assert d["is_none"] is False
    assert d["operator()"] == 2
    assert d["operator*"] == 7
    assert d["implicit_list"] == [1, 2, 3]
    assert all(x in TestObject.__dict__ for x in d["implicit_dict"])

    assert m.tuple_accessor(tuple()) == (0, 1, 2)

    d = m.accessor_assignment()
    assert d["get"] == 0
    assert d["deferred_get"] == 0
    assert d["set"] == 1
    assert d["deferred_set"] == 1
    assert d["var"] == 99


def test_constructors():
    """C++ default and converting constructors are equivalent to type calls in Python"""
    types = [str, bool, int, float, tuple, list, dict, set]
    expected = {t.__name__: t() for t in types}
    assert m.default_constructors() == expected

    data = {
        str: 42,
        bool: "Not empty",
        int: "42",
        float: "+1e3",
        tuple: range(3),
        list: range(3),
        dict: [("two", 2), ("one", 1), ("three", 3)],
        set: [4, 4, 5, 6, 6, 6],
        memoryview: b'abc'
    }
    inputs = {k.__name__: v for k, v in data.items()}
    expected = {k.__name__: k(v) for k, v in data.items()}

    assert m.converting_constructors(inputs) == expected
    assert m.cast_functions(inputs) == expected

    # Converting constructors and cast functions should just reference rather
    # than copy when no conversion is needed:
    noconv1 = m.converting_constructors(expected)
    for k in noconv1:
        assert noconv1[k] is expected[k]

    noconv2 = m.cast_functions(expected)
    for k in noconv2:
        assert noconv2[k] is expected[k]


def test_implicit_casting():
    """Tests implicit casting when assigning or appending to dicts and lists."""
    z = m.get_implicit_casting()
    assert z['d'] == {
        'char*_i1': 'abc', 'char*_i2': 'abc', 'char*_e': 'abc', 'char*_p': 'abc',
        'str_i1': 'str', 'str_i2': 'str1', 'str_e': 'str2', 'str_p': 'str3',
        'int_i1': 42, 'int_i2': 42, 'int_e': 43, 'int_p': 44
    }
    assert z['l'] == [3, 6, 9, 12, 15]


def test_print(capture):
    with capture:
        m.print_function()
    assert capture == """
        Hello, World!
        1 2.0 three True -- multiple args
        *args-and-a-custom-separator
        no new line here -- next print
        flush
        py::print + str.format = this
    """
    assert capture.stderr == "this goes to stderr"

    with pytest.raises(RuntimeError) as excinfo:
        m.print_failure()
    assert str(excinfo.value) == "make_tuple(): unable to convert " + (
        "argument of type 'UnregisteredType' to Python object"
        if debug_enabled else
        "arguments to Python object (compile in debug mode for details)"
    )


def test_hash():
    class Hashable(object):
        def __init__(self, value):
            self.value = value

        def __hash__(self):
            return self.value

    class Unhashable(object):
        __hash__ = None

    assert m.hash_function(Hashable(42)) == 42
    with pytest.raises(TypeError):
        m.hash_function(Unhashable())