pybind11/tests/test_numpy_array.py
pre-commit-ci[bot] 8a801bdc32
chore(deps): update pre-commit hooks (#5350)
* chore(deps): update pre-commit hooks

updates:
- [github.com/astral-sh/ruff-pre-commit: v0.5.6 → v0.6.3](https://github.com/astral-sh/ruff-pre-commit/compare/v0.5.6...v0.6.3)
- [github.com/pre-commit/mirrors-mypy: v1.11.1 → v1.11.2](https://github.com/pre-commit/mirrors-mypy/compare/v1.11.1...v1.11.2)
- [github.com/sirosen/texthooks: 0.6.6 → 0.6.7](https://github.com/sirosen/texthooks/compare/0.6.6...0.6.7)
- [github.com/PyCQA/pylint: v3.2.6 → v3.2.7](https://github.com/PyCQA/pylint/compare/v3.2.6...v3.2.7)
- [github.com/python-jsonschema/check-jsonschema: 0.29.1 → 0.29.2](https://github.com/python-jsonschema/check-jsonschema/compare/0.29.1...0.29.2)

* style: pre-commit fixes

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
2024-09-03 10:51:21 -04:00

673 lines
22 KiB
Python

from __future__ import annotations
import pytest
import env # noqa: F401
from pybind11_tests import numpy_array as m
np = pytest.importorskip("numpy")
def test_dtypes():
# See issue #1328.
# - Platform-dependent sizes.
for size_check in m.get_platform_dtype_size_checks():
print(size_check)
assert size_check.size_cpp == size_check.size_numpy, size_check
# - Concrete sizes.
for check in m.get_concrete_dtype_checks():
print(check)
assert check.numpy == check.pybind11, check
if check.numpy.num != check.pybind11.num:
print(
f"NOTE: typenum mismatch for {check}: {check.numpy.num} != {check.pybind11.num}"
)
@pytest.fixture
def arr():
return np.array([[1, 2, 3], [4, 5, 6]], "=u2")
def test_array_attributes():
a = np.array(0, "f8")
assert m.ndim(a) == 0
assert all(m.shape(a) == [])
assert all(m.strides(a) == [])
with pytest.raises(IndexError) as excinfo:
m.shape(a, 0)
assert str(excinfo.value) == "invalid axis: 0 (ndim = 0)"
with pytest.raises(IndexError) as excinfo:
m.strides(a, 0)
assert str(excinfo.value) == "invalid axis: 0 (ndim = 0)"
assert m.writeable(a)
assert m.size(a) == 1
assert m.itemsize(a) == 8
assert m.nbytes(a) == 8
assert m.owndata(a)
a = np.array([[1, 2, 3], [4, 5, 6]], "u2").view()
a.flags.writeable = False
assert m.ndim(a) == 2
assert all(m.shape(a) == [2, 3])
assert m.shape(a, 0) == 2
assert m.shape(a, 1) == 3
assert all(m.strides(a) == [6, 2])
assert m.strides(a, 0) == 6
assert m.strides(a, 1) == 2
with pytest.raises(IndexError) as excinfo:
m.shape(a, 2)
assert str(excinfo.value) == "invalid axis: 2 (ndim = 2)"
with pytest.raises(IndexError) as excinfo:
m.strides(a, 2)
assert str(excinfo.value) == "invalid axis: 2 (ndim = 2)"
assert not m.writeable(a)
assert m.size(a) == 6
assert m.itemsize(a) == 2
assert m.nbytes(a) == 12
assert not m.owndata(a)
@pytest.mark.parametrize(
("args", "ret"), [([], 0), ([0], 0), ([1], 3), ([0, 1], 1), ([1, 2], 5)]
)
def test_index_offset(arr, args, ret):
assert m.index_at(arr, *args) == ret
assert m.index_at_t(arr, *args) == ret
assert m.offset_at(arr, *args) == ret * arr.dtype.itemsize
assert m.offset_at_t(arr, *args) == ret * arr.dtype.itemsize
def test_dim_check_fail(arr):
for func in (
m.index_at,
m.index_at_t,
m.offset_at,
m.offset_at_t,
m.data,
m.data_t,
m.mutate_data,
m.mutate_data_t,
):
with pytest.raises(IndexError) as excinfo:
func(arr, 1, 2, 3)
assert str(excinfo.value) == "too many indices for an array: 3 (ndim = 2)"
@pytest.mark.parametrize(
("args", "ret"),
[
([], [1, 2, 3, 4, 5, 6]),
([1], [4, 5, 6]),
([0, 1], [2, 3, 4, 5, 6]),
([1, 2], [6]),
],
)
def test_data(arr, args, ret):
from sys import byteorder
assert all(m.data_t(arr, *args) == ret)
assert all(m.data(arr, *args)[(0 if byteorder == "little" else 1) :: 2] == ret)
assert all(m.data(arr, *args)[(1 if byteorder == "little" else 0) :: 2] == 0)
@pytest.mark.parametrize("dim", [0, 1, 3])
def test_at_fail(arr, dim):
for func in m.at_t, m.mutate_at_t:
with pytest.raises(IndexError) as excinfo:
func(arr, *([0] * dim))
assert str(excinfo.value) == f"index dimension mismatch: {dim} (ndim = 2)"
def test_at(arr):
assert m.at_t(arr, 0, 2) == 3
assert m.at_t(arr, 1, 0) == 4
assert all(m.mutate_at_t(arr, 0, 2).ravel() == [1, 2, 4, 4, 5, 6])
assert all(m.mutate_at_t(arr, 1, 0).ravel() == [1, 2, 4, 5, 5, 6])
def test_mutate_readonly(arr):
arr.flags.writeable = False
for func, args in (
(m.mutate_data, ()),
(m.mutate_data_t, ()),
(m.mutate_at_t, (0, 0)),
):
with pytest.raises(ValueError) as excinfo:
func(arr, *args)
assert str(excinfo.value) == "array is not writeable"
def test_mutate_data(arr):
assert all(m.mutate_data(arr).ravel() == [2, 4, 6, 8, 10, 12])
assert all(m.mutate_data(arr).ravel() == [4, 8, 12, 16, 20, 24])
assert all(m.mutate_data(arr, 1).ravel() == [4, 8, 12, 32, 40, 48])
assert all(m.mutate_data(arr, 0, 1).ravel() == [4, 16, 24, 64, 80, 96])
assert all(m.mutate_data(arr, 1, 2).ravel() == [4, 16, 24, 64, 80, 192])
assert all(m.mutate_data_t(arr).ravel() == [5, 17, 25, 65, 81, 193])
assert all(m.mutate_data_t(arr).ravel() == [6, 18, 26, 66, 82, 194])
assert all(m.mutate_data_t(arr, 1).ravel() == [6, 18, 26, 67, 83, 195])
assert all(m.mutate_data_t(arr, 0, 1).ravel() == [6, 19, 27, 68, 84, 196])
assert all(m.mutate_data_t(arr, 1, 2).ravel() == [6, 19, 27, 68, 84, 197])
def test_bounds_check(arr):
for func in (
m.index_at,
m.index_at_t,
m.data,
m.data_t,
m.mutate_data,
m.mutate_data_t,
m.at_t,
m.mutate_at_t,
):
with pytest.raises(IndexError) as excinfo:
func(arr, 2, 0)
assert str(excinfo.value) == "index 2 is out of bounds for axis 0 with size 2"
with pytest.raises(IndexError) as excinfo:
func(arr, 0, 4)
assert str(excinfo.value) == "index 4 is out of bounds for axis 1 with size 3"
def test_make_c_f_array():
assert m.make_c_array().flags.c_contiguous
assert not m.make_c_array().flags.f_contiguous
assert m.make_f_array().flags.f_contiguous
assert not m.make_f_array().flags.c_contiguous
def test_make_empty_shaped_array():
m.make_empty_shaped_array()
# empty shape means numpy scalar, PEP 3118
assert m.scalar_int().ndim == 0
assert m.scalar_int().shape == ()
assert m.scalar_int() == 42
def test_wrap():
def assert_references(a, b, base=None):
if base is None:
base = a
assert a is not b
assert a.__array_interface__["data"][0] == b.__array_interface__["data"][0]
assert a.shape == b.shape
assert a.strides == b.strides
assert a.flags.c_contiguous == b.flags.c_contiguous
assert a.flags.f_contiguous == b.flags.f_contiguous
assert a.flags.writeable == b.flags.writeable
assert a.flags.aligned == b.flags.aligned
assert a.flags.writebackifcopy == b.flags.writebackifcopy
assert np.all(a == b)
assert not b.flags.owndata
assert b.base is base
if a.flags.writeable and a.ndim == 2:
a[0, 0] = 1234
assert b[0, 0] == 1234
a1 = np.array([1, 2], dtype=np.int16)
assert a1.flags.owndata
assert a1.base is None
a2 = m.wrap(a1)
assert_references(a1, a2)
a1 = np.array([[1, 2], [3, 4]], dtype=np.float32, order="F")
assert a1.flags.owndata
assert a1.base is None
a2 = m.wrap(a1)
assert_references(a1, a2)
a1 = np.array([[1, 2], [3, 4]], dtype=np.float32, order="C")
a1.flags.writeable = False
a2 = m.wrap(a1)
assert_references(a1, a2)
a1 = np.random.random((4, 4, 4))
a2 = m.wrap(a1)
assert_references(a1, a2)
a1t = a1.transpose()
a2 = m.wrap(a1t)
assert_references(a1t, a2, a1)
a1d = a1.diagonal()
a2 = m.wrap(a1d)
assert_references(a1d, a2, a1)
a1m = a1[::-1, ::-1, ::-1]
a2 = m.wrap(a1m)
assert_references(a1m, a2, a1)
def test_numpy_view(capture):
with capture:
ac = m.ArrayClass()
ac_view_1 = ac.numpy_view()
ac_view_2 = ac.numpy_view()
assert np.all(ac_view_1 == np.array([1, 2], dtype=np.int32))
del ac
pytest.gc_collect()
assert (
capture
== """
ArrayClass()
ArrayClass::numpy_view()
ArrayClass::numpy_view()
"""
)
ac_view_1[0] = 4
ac_view_1[1] = 3
assert ac_view_2[0] == 4
assert ac_view_2[1] == 3
with capture:
del ac_view_1
del ac_view_2
pytest.gc_collect()
pytest.gc_collect()
assert (
capture
== """
~ArrayClass()
"""
)
def test_cast_numpy_int64_to_uint64():
m.function_taking_uint64(123)
m.function_taking_uint64(np.uint64(123))
def test_isinstance():
assert m.isinstance_untyped(np.array([1, 2, 3]), "not an array")
assert m.isinstance_typed(np.array([1.0, 2.0, 3.0]))
def test_constructors():
defaults = m.default_constructors()
for a in defaults.values():
assert a.size == 0
assert defaults["array"].dtype == np.array([]).dtype
assert defaults["array_t<int32>"].dtype == np.int32
assert defaults["array_t<double>"].dtype == np.float64
results = m.converting_constructors([1, 2, 3])
for a in results.values():
np.testing.assert_array_equal(a, [1, 2, 3])
assert results["array"].dtype == np.dtype(int)
assert results["array_t<int32>"].dtype == np.int32
assert results["array_t<double>"].dtype == np.float64
def test_overload_resolution(msg):
# Exact overload matches:
assert m.overloaded(np.array([1], dtype="float64")) == "double"
assert m.overloaded(np.array([1], dtype="float32")) == "float"
assert m.overloaded(np.array([1], dtype="ushort")) == "unsigned short"
assert m.overloaded(np.array([1], dtype="intc")) == "int"
assert m.overloaded(np.array([1], dtype="longlong")) == "long long"
assert m.overloaded(np.array([1], dtype="complex")) == "double complex"
assert m.overloaded(np.array([1], dtype="csingle")) == "float complex"
# No exact match, should call first convertible version:
assert m.overloaded(np.array([1], dtype="uint8")) == "double"
with pytest.raises(TypeError) as excinfo:
m.overloaded("not an array")
assert (
msg(excinfo.value)
== """
overloaded(): incompatible function arguments. The following argument types are supported:
1. (arg0: numpy.ndarray[numpy.float64]) -> str
2. (arg0: numpy.ndarray[numpy.float32]) -> str
3. (arg0: numpy.ndarray[numpy.int32]) -> str
4. (arg0: numpy.ndarray[numpy.uint16]) -> str
5. (arg0: numpy.ndarray[numpy.int64]) -> str
6. (arg0: numpy.ndarray[numpy.complex128]) -> str
7. (arg0: numpy.ndarray[numpy.complex64]) -> str
Invoked with: 'not an array'
"""
)
assert m.overloaded2(np.array([1], dtype="float64")) == "double"
assert m.overloaded2(np.array([1], dtype="float32")) == "float"
assert m.overloaded2(np.array([1], dtype="complex64")) == "float complex"
assert m.overloaded2(np.array([1], dtype="complex128")) == "double complex"
assert m.overloaded2(np.array([1], dtype="float32")) == "float"
assert m.overloaded3(np.array([1], dtype="float64")) == "double"
assert m.overloaded3(np.array([1], dtype="intc")) == "int"
expected_exc = """
overloaded3(): incompatible function arguments. The following argument types are supported:
1. (arg0: numpy.ndarray[numpy.int32]) -> str
2. (arg0: numpy.ndarray[numpy.float64]) -> str
Invoked with: """
with pytest.raises(TypeError) as excinfo:
m.overloaded3(np.array([1], dtype="uintc"))
assert msg(excinfo.value) == expected_exc + repr(np.array([1], dtype="uint32"))
with pytest.raises(TypeError) as excinfo:
m.overloaded3(np.array([1], dtype="float32"))
assert msg(excinfo.value) == expected_exc + repr(np.array([1.0], dtype="float32"))
with pytest.raises(TypeError) as excinfo:
m.overloaded3(np.array([1], dtype="complex"))
assert msg(excinfo.value) == expected_exc + repr(np.array([1.0 + 0.0j]))
# Exact matches:
assert m.overloaded4(np.array([1], dtype="double")) == "double"
assert m.overloaded4(np.array([1], dtype="longlong")) == "long long"
# Non-exact matches requiring conversion. Since float to integer isn't a
# save conversion, it should go to the double overload, but short can go to
# either (and so should end up on the first-registered, the long long).
assert m.overloaded4(np.array([1], dtype="float32")) == "double"
assert m.overloaded4(np.array([1], dtype="short")) == "long long"
assert m.overloaded5(np.array([1], dtype="double")) == "double"
assert m.overloaded5(np.array([1], dtype="uintc")) == "unsigned int"
assert m.overloaded5(np.array([1], dtype="float32")) == "unsigned int"
def test_greedy_string_overload():
"""Tests fix for #685 - ndarray shouldn't go to std::string overload"""
assert m.issue685("abc") == "string"
assert m.issue685(np.array([97, 98, 99], dtype="b")) == "array"
assert m.issue685(123) == "other"
def test_array_unchecked_fixed_dims(msg):
z1 = np.array([[1, 2], [3, 4]], dtype="float64")
m.proxy_add2(z1, 10)
assert np.all(z1 == [[11, 12], [13, 14]])
with pytest.raises(ValueError) as excinfo:
m.proxy_add2(np.array([1.0, 2, 3]), 5.0)
assert (
msg(excinfo.value) == "array has incorrect number of dimensions: 1; expected 2"
)
expect_c = np.ndarray(shape=(3, 3, 3), buffer=np.array(range(3, 30)), dtype="int")
assert np.all(m.proxy_init3(3.0) == expect_c)
expect_f = np.transpose(expect_c)
assert np.all(m.proxy_init3F(3.0) == expect_f)
assert m.proxy_squared_L2_norm(np.array(range(6))) == 55
assert m.proxy_squared_L2_norm(np.array(range(6), dtype="float64")) == 55
assert m.proxy_auxiliaries2(z1) == [11, 11, True, 2, 8, 2, 2, 4, 32]
assert m.proxy_auxiliaries2(z1) == m.array_auxiliaries2(z1)
assert m.proxy_auxiliaries1_const_ref(z1[0, :])
assert m.proxy_auxiliaries2_const_ref(z1)
def test_array_unchecked_dyn_dims():
z1 = np.array([[1, 2], [3, 4]], dtype="float64")
m.proxy_add2_dyn(z1, 10)
assert np.all(z1 == [[11, 12], [13, 14]])
expect_c = np.ndarray(shape=(3, 3, 3), buffer=np.array(range(3, 30)), dtype="int")
assert np.all(m.proxy_init3_dyn(3.0) == expect_c)
assert m.proxy_auxiliaries2_dyn(z1) == [11, 11, True, 2, 8, 2, 2, 4, 32]
assert m.proxy_auxiliaries2_dyn(z1) == m.array_auxiliaries2(z1)
def test_array_failure():
with pytest.raises(ValueError) as excinfo:
m.array_fail_test()
assert str(excinfo.value) == "cannot create a pybind11::array from a nullptr"
with pytest.raises(ValueError) as excinfo:
m.array_t_fail_test()
assert str(excinfo.value) == "cannot create a pybind11::array_t from a nullptr"
with pytest.raises(ValueError) as excinfo:
m.array_fail_test_negative_size()
assert str(excinfo.value) == "negative dimensions are not allowed"
def test_initializer_list():
assert m.array_initializer_list1().shape == (1,)
assert m.array_initializer_list2().shape == (1, 2)
assert m.array_initializer_list3().shape == (1, 2, 3)
assert m.array_initializer_list4().shape == (1, 2, 3, 4)
def test_array_resize():
a = np.array([1, 2, 3, 4, 5, 6, 7, 8, 9], dtype="float64")
m.array_reshape2(a)
assert a.size == 9
assert np.all(a == [[1, 2, 3], [4, 5, 6], [7, 8, 9]])
# total size change should succced with refcheck off
m.array_resize3(a, 4, False)
assert a.size == 64
# ... and fail with refcheck on
try:
m.array_resize3(a, 3, True)
except ValueError as e:
assert str(e).startswith("cannot resize an array") # noqa: PT017
# transposed array doesn't own data
b = a.transpose()
try:
m.array_resize3(b, 3, False)
except ValueError as e:
assert str(e).startswith( # noqa: PT017
"cannot resize this array: it does not own its data"
)
# ... but reshape should be fine
m.array_reshape2(b)
assert b.shape == (8, 8)
@pytest.mark.xfail("env.PYPY")
def test_array_create_and_resize():
a = m.create_and_resize(2)
assert a.size == 4
assert np.all(a == 42.0)
def test_array_view():
a = np.ones(100 * 4).astype("uint8")
a_float_view = m.array_view(a, "float32")
assert a_float_view.shape == (100 * 1,) # 1 / 4 bytes = 8 / 32
a_int16_view = m.array_view(a, "int16") # 1 / 2 bytes = 16 / 32
assert a_int16_view.shape == (100 * 2,)
def test_array_view_invalid():
a = np.ones(100 * 4).astype("uint8")
with pytest.raises(TypeError):
m.array_view(a, "deadly_dtype")
def test_reshape_initializer_list():
a = np.arange(2 * 7 * 3) + 1
x = m.reshape_initializer_list(a, 2, 7, 3)
assert x.shape == (2, 7, 3)
assert list(x[1][4]) == [34, 35, 36]
with pytest.raises(ValueError) as excinfo:
m.reshape_initializer_list(a, 1, 7, 3)
assert str(excinfo.value) == "cannot reshape array of size 42 into shape (1,7,3)"
def test_reshape_tuple():
a = np.arange(3 * 7 * 2) + 1
x = m.reshape_tuple(a, (3, 7, 2))
assert x.shape == (3, 7, 2)
assert list(x[1][4]) == [23, 24]
y = m.reshape_tuple(x, (x.size,))
assert y.shape == (42,)
with pytest.raises(ValueError) as excinfo:
m.reshape_tuple(a, (3, 7, 1))
assert str(excinfo.value) == "cannot reshape array of size 42 into shape (3,7,1)"
with pytest.raises(ValueError) as excinfo:
m.reshape_tuple(a, ())
assert str(excinfo.value) == "cannot reshape array of size 42 into shape ()"
def test_index_using_ellipsis():
a = m.index_using_ellipsis(np.zeros((5, 6, 7)))
assert a.shape == (6,)
@pytest.mark.parametrize(
"test_func",
[
m.test_fmt_desc_float,
m.test_fmt_desc_double,
m.test_fmt_desc_const_float,
m.test_fmt_desc_const_double,
],
)
def test_format_descriptors_for_floating_point_types(test_func):
assert "numpy.ndarray[numpy.float" in test_func.__doc__
@pytest.mark.parametrize("forcecast", [False, True])
@pytest.mark.parametrize("contiguity", [None, "C", "F"])
@pytest.mark.parametrize("noconvert", [False, True])
@pytest.mark.filterwarnings(
"ignore:Casting complex values to real discards the imaginary part:"
+ (
"numpy.exceptions.ComplexWarning"
if hasattr(np, "exceptions")
else "numpy.ComplexWarning"
)
)
def test_argument_conversions(forcecast, contiguity, noconvert):
function_name = "accept_double"
if contiguity == "C":
function_name += "_c_style"
elif contiguity == "F":
function_name += "_f_style"
if forcecast:
function_name += "_forcecast"
if noconvert:
function_name += "_noconvert"
function = getattr(m, function_name)
for dtype in [np.dtype("float32"), np.dtype("float64"), np.dtype("complex128")]:
for order in ["C", "F"]:
for shape in [(2, 2), (1, 3, 1, 1), (1, 1, 1), (0,)]:
if not noconvert:
# If noconvert is not passed, only complex128 needs to be truncated and
# "cannot be safely obtained". So without `forcecast`, the argument shouldn't
# be accepted.
should_raise = dtype.name == "complex128" and not forcecast
else:
# If noconvert is passed, only float64 and the matching order is accepted.
# If at most one dimension has a size greater than 1, the array is also
# trivially contiguous.
trivially_contiguous = sum(1 for d in shape if d > 1) <= 1
should_raise = dtype.name != "float64" or (
contiguity is not None
and contiguity != order
and not trivially_contiguous
)
array = np.zeros(shape, dtype=dtype, order=order)
if not should_raise:
function(array)
else:
with pytest.raises(
TypeError, match="incompatible function arguments"
):
function(array)
@pytest.mark.xfail("env.PYPY")
def test_dtype_refcount_leak():
from sys import getrefcount
# Was np.float_ but that alias for float64 was removed in NumPy 2.
dtype = np.dtype(np.float64)
a = np.array([1], dtype=dtype)
before = getrefcount(dtype)
m.ndim(a)
after = getrefcount(dtype)
assert after == before
def test_round_trip_float():
arr = np.zeros((), np.float64)
arr[()] = 37.2
assert m.round_trip_float(arr) == 37.2
# HINT: An easy and robust way (although only manual unfortunately) to check for
# ref-count leaks in the test_.*pyobject_ptr.* functions below is to
# * temporarily insert `while True:` (one-by-one),
# * run this test, and
# * run the Linux `top` command in another shell to visually monitor
# `RES` for a minute or two.
# If there is a leak, it is usually evident in seconds because the `RES`
# value increases without bounds. (Don't forget to Ctrl-C the test!)
# For use as a temporary user-defined object, to maximize sensitivity of the tests below:
# * Ref-count leaks will be immediately evident.
# * Sanitizers are much more likely to detect heap-use-after-free due to
# other ref-count bugs.
class PyValueHolder:
def __init__(self, value):
self.value = value
def WrapWithPyValueHolder(*values):
return [PyValueHolder(v) for v in values]
def UnwrapPyValueHolder(vhs):
return [vh.value for vh in vhs]
def test_pass_array_pyobject_ptr_return_sum_str_values_ndarray():
# Intentionally all temporaries, do not change.
assert (
m.pass_array_pyobject_ptr_return_sum_str_values(
np.array(WrapWithPyValueHolder(-3, "four", 5.0), dtype=object)
)
== "-3four5.0"
)
def test_pass_array_pyobject_ptr_return_sum_str_values_list():
# Intentionally all temporaries, do not change.
assert (
m.pass_array_pyobject_ptr_return_sum_str_values(
WrapWithPyValueHolder(2, "three", -4.0)
)
== "2three-4.0"
)
def test_pass_array_pyobject_ptr_return_as_list():
# Intentionally all temporaries, do not change.
assert UnwrapPyValueHolder(
m.pass_array_pyobject_ptr_return_as_list(
np.array(WrapWithPyValueHolder(-1, "two", 3.0), dtype=object)
)
) == [-1, "two", 3.0]
@pytest.mark.parametrize(
("return_array_pyobject_ptr", "unwrap"),
[
(m.return_array_pyobject_ptr_cpp_loop, list),
(m.return_array_pyobject_ptr_from_list, UnwrapPyValueHolder),
],
)
def test_return_array_pyobject_ptr_cpp_loop(return_array_pyobject_ptr, unwrap):
# Intentionally all temporaries, do not change.
arr_from_list = return_array_pyobject_ptr(WrapWithPyValueHolder(6, "seven", -8.0))
assert isinstance(arr_from_list, np.ndarray)
assert arr_from_list.dtype == np.dtype("O")
assert unwrap(arr_from_list) == [6, "seven", -8.0]