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@@ -369,3 +369,6 @@ tuning-competition-baseline/.venv/lib/python3.11/site-packages/nvidia/cudnn/lib/
 .venv/lib/python3.11/site-packages/numpy/random/tests/__pycache__/test_random.cpython-311.pyc filter=lfs diff=lfs merge=lfs -text
 .venv/lib/python3.11/site-packages/numpy/random/mtrand.cpython-311-x86_64-linux-gnu.so filter=lfs diff=lfs merge=lfs -text
 .venv/lib/python3.11/site-packages/numpy/random/tests/__pycache__/test_randomstate.cpython-311.pyc filter=lfs diff=lfs merge=lfs -text
+.venv/lib/python3.11/site-packages/numpy/core/_multiarray_umath.cpython-311-x86_64-linux-gnu.so filter=lfs diff=lfs merge=lfs -text
+.venv/lib/python3.11/site-packages/numpy/core/_multiarray_tests.cpython-311-x86_64-linux-gnu.so filter=lfs diff=lfs merge=lfs -text
+.venv/lib/python3.11/site-packages/numpy/core/_simd.cpython-311-x86_64-linux-gnu.so filter=lfs diff=lfs merge=lfs -text

.venv/lib/python3.11/site-packages/numpy/core/_multiarray_tests.cpython-311-x86_64-linux-gnu.so

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.venv/lib/python3.11/site-packages/numpy/core/_multiarray_umath.cpython-311-x86_64-linux-gnu.so

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.venv/lib/python3.11/site-packages/numpy/core/_simd.cpython-311-x86_64-linux-gnu.so

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.venv/lib/python3.11/site-packages/numpy/core/tests/_locales.py

@@ -0,0 +1,74 @@
+"""Provide class for testing in French locale
+
+"""
+import sys
+import locale
+
+import pytest
+
+__ALL__ = ['CommaDecimalPointLocale']
+
+
+def find_comma_decimal_point_locale():
+    """See if platform has a decimal point as comma locale.
+
+    Find a locale that uses a comma instead of a period as the
+    decimal point.
+
+    Returns
+    -------
+    old_locale: str
+        Locale when the function was called.
+    new_locale: {str, None)
+        First French locale found, None if none found.
+
+    """
+    if sys.platform == 'win32':
+        locales = ['FRENCH']
+    else:
+        locales = ['fr_FR', 'fr_FR.UTF-8', 'fi_FI', 'fi_FI.UTF-8']
+
+    old_locale = locale.getlocale(locale.LC_NUMERIC)
+    new_locale = None
+    try:
+        for loc in locales:
+            try:
+                locale.setlocale(locale.LC_NUMERIC, loc)
+                new_locale = loc
+                break
+            except locale.Error:
+                pass
+    finally:
+        locale.setlocale(locale.LC_NUMERIC, locale=old_locale)
+    return old_locale, new_locale
+
+
+class CommaDecimalPointLocale:
+    """Sets LC_NUMERIC to a locale with comma as decimal point.
+
+    Classes derived from this class have setup and teardown methods that run
+    tests with locale.LC_NUMERIC set to a locale where commas (',') are used as
+    the decimal point instead of periods ('.'). On exit the locale is restored
+    to the initial locale. It also serves as context manager with the same
+    effect. If no such locale is available, the test is skipped.
+
+    .. versionadded:: 1.15.0
+
+    """
+    (cur_locale, tst_locale) = find_comma_decimal_point_locale()
+
+    def setup_method(self):
+        if self.tst_locale is None:
+            pytest.skip("No French locale available")
+        locale.setlocale(locale.LC_NUMERIC, locale=self.tst_locale)
+
+    def teardown_method(self):
+        locale.setlocale(locale.LC_NUMERIC, locale=self.cur_locale)
+
+    def __enter__(self):
+        if self.tst_locale is None:
+            pytest.skip("No French locale available")
+        locale.setlocale(locale.LC_NUMERIC, locale=self.tst_locale)
+
+    def __exit__(self, type, value, traceback):
+        locale.setlocale(locale.LC_NUMERIC, locale=self.cur_locale)

.venv/lib/python3.11/site-packages/numpy/core/tests/test__exceptions.py

@@ -0,0 +1,88 @@
+"""
+Tests of the ._exceptions module. Primarily for exercising the __str__ methods.
+"""
+
+import pickle
+
+import pytest
+import numpy as np
+
+_ArrayMemoryError = np.core._exceptions._ArrayMemoryError
+_UFuncNoLoopError = np.core._exceptions._UFuncNoLoopError
+
+class TestArrayMemoryError:
+    def test_pickling(self):
+        """ Test that _ArrayMemoryError can be pickled """
+        error = _ArrayMemoryError((1023,), np.dtype(np.uint8))
+        res = pickle.loads(pickle.dumps(error))
+        assert res._total_size == error._total_size
+
+    def test_str(self):
+        e = _ArrayMemoryError((1023,), np.dtype(np.uint8))
+        str(e)  # not crashing is enough
+
+    # testing these properties is easier than testing the full string repr
+    def test__size_to_string(self):
+        """ Test e._size_to_string """
+        f = _ArrayMemoryError._size_to_string
+        Ki = 1024
+        assert f(0) == '0 bytes'
+        assert f(1) == '1 bytes'
+        assert f(1023) == '1023 bytes'
+        assert f(Ki) == '1.00 KiB'
+        assert f(Ki+1) == '1.00 KiB'
+        assert f(10*Ki) == '10.0 KiB'
+        assert f(int(999.4*Ki)) == '999. KiB'
+        assert f(int(1023.4*Ki)) == '1023. KiB'
+        assert f(int(1023.5*Ki)) == '1.00 MiB'
+        assert f(Ki*Ki) == '1.00 MiB'
+
+        # 1023.9999 Mib should round to 1 GiB
+        assert f(int(Ki*Ki*Ki*0.9999)) == '1.00 GiB'
+        assert f(Ki*Ki*Ki*Ki*Ki*Ki) == '1.00 EiB'
+        # larger than sys.maxsize, adding larger prefixes isn't going to help
+        # anyway.
+        assert f(Ki*Ki*Ki*Ki*Ki*Ki*123456) == '123456. EiB'
+
+    def test__total_size(self):
+        """ Test e._total_size """
+        e = _ArrayMemoryError((1,), np.dtype(np.uint8))
+        assert e._total_size == 1
+
+        e = _ArrayMemoryError((2, 4), np.dtype((np.uint64, 16)))
+        assert e._total_size == 1024
+
+
+class TestUFuncNoLoopError:
+    def test_pickling(self):
+        """ Test that _UFuncNoLoopError can be pickled """
+        assert isinstance(pickle.dumps(_UFuncNoLoopError), bytes)
+
+
+@pytest.mark.parametrize("args", [
+    (2, 1, None),
+    (2, 1, "test_prefix"),
+    ("test message",),
+])
+class TestAxisError:
+    def test_attr(self, args):
+        """Validate attribute types."""
+        exc = np.AxisError(*args)
+        if len(args) == 1:
+            assert exc.axis is None
+            assert exc.ndim is None
+        else:
+            axis, ndim, *_ = args
+            assert exc.axis == axis
+            assert exc.ndim == ndim
+
+    def test_pickling(self, args):
+        """Test that `AxisError` can be pickled."""
+        exc = np.AxisError(*args)
+        exc2 = pickle.loads(pickle.dumps(exc))
+
+        assert type(exc) is type(exc2)
+        for name in ("axis", "ndim", "args"):
+            attr1 = getattr(exc, name)
+            attr2 = getattr(exc2, name)
+            assert attr1 == attr2, name

.venv/lib/python3.11/site-packages/numpy/core/tests/test_abc.py

@@ -0,0 +1,54 @@
+from numpy.testing import assert_
+
+import numbers
+
+import numpy as np
+from numpy.core.numerictypes import sctypes
+
+class TestABC:
+    def test_abstract(self):
+        assert_(issubclass(np.number, numbers.Number))
+
+        assert_(issubclass(np.inexact, numbers.Complex))
+        assert_(issubclass(np.complexfloating, numbers.Complex))
+        assert_(issubclass(np.floating, numbers.Real))
+
+        assert_(issubclass(np.integer, numbers.Integral))
+        assert_(issubclass(np.signedinteger, numbers.Integral))
+        assert_(issubclass(np.unsignedinteger, numbers.Integral))
+
+    def test_floats(self):
+        for t in sctypes['float']:
+            assert_(isinstance(t(), numbers.Real),
+                    f"{t.__name__} is not instance of Real")
+            assert_(issubclass(t, numbers.Real),
+                    f"{t.__name__} is not subclass of Real")
+            assert_(not isinstance(t(), numbers.Rational),
+                    f"{t.__name__} is instance of Rational")
+            assert_(not issubclass(t, numbers.Rational),
+                    f"{t.__name__} is subclass of Rational")
+
+    def test_complex(self):
+        for t in sctypes['complex']:
+            assert_(isinstance(t(), numbers.Complex),
+                    f"{t.__name__} is not instance of Complex")
+            assert_(issubclass(t, numbers.Complex),
+                    f"{t.__name__} is not subclass of Complex")
+            assert_(not isinstance(t(), numbers.Real),
+                    f"{t.__name__} is instance of Real")
+            assert_(not issubclass(t, numbers.Real),
+                    f"{t.__name__} is subclass of Real")
+
+    def test_int(self):
+        for t in sctypes['int']:
+            assert_(isinstance(t(), numbers.Integral),
+                    f"{t.__name__} is not instance of Integral")
+            assert_(issubclass(t, numbers.Integral),
+                    f"{t.__name__} is not subclass of Integral")
+
+    def test_uint(self):
+        for t in sctypes['uint']:
+            assert_(isinstance(t(), numbers.Integral),
+                    f"{t.__name__} is not instance of Integral")
+            assert_(issubclass(t, numbers.Integral),
+                    f"{t.__name__} is not subclass of Integral")

.venv/lib/python3.11/site-packages/numpy/core/tests/test_argparse.py

@@ -0,0 +1,62 @@
+"""
+Tests for the private NumPy argument parsing functionality.
+They mainly exists to ensure good test coverage without having to try the
+weirder cases on actual numpy functions but test them in one place.
+
+The test function is defined in C to be equivalent to (errors may not always
+match exactly, and could be adjusted):
+
+    def func(arg1, /, arg2, *, arg3):
+        i = integer(arg1)  # reproducing the 'i' parsing in Python.
+        return None
+"""
+
+import pytest
+
+import numpy as np
+from numpy.core._multiarray_tests import argparse_example_function as func
+
+
+def test_invalid_integers():
+    with pytest.raises(TypeError,
+            match="integer argument expected, got float"):
+        func(1.)
+    with pytest.raises(OverflowError):
+        func(2**100)
+
+
+def test_missing_arguments():
+    with pytest.raises(TypeError,
+            match="missing required positional argument 0"):
+        func()
+    with pytest.raises(TypeError,
+            match="missing required positional argument 0"):
+        func(arg2=1, arg3=4)
+    with pytest.raises(TypeError,
+            match=r"missing required argument \'arg2\' \(pos 1\)"):
+        func(1, arg3=5)
+
+
+def test_too_many_positional():
+    # the second argument is positional but can be passed as keyword.
+    with pytest.raises(TypeError,
+            match="takes from 2 to 3 positional arguments but 4 were given"):
+        func(1, 2, 3, 4)
+
+
+def test_multiple_values():
+    with pytest.raises(TypeError,
+            match=r"given by name \('arg2'\) and position \(position 1\)"):
+        func(1, 2, arg2=3)
+
+
+def test_string_fallbacks():
+    # We can (currently?) use numpy strings to test the "slow" fallbacks
+    # that should normally not be taken due to string interning.
+    arg2 = np.str_("arg2")
+    missing_arg = np.str_("missing_arg")
+    func(1, **{arg2: 3})
+    with pytest.raises(TypeError,
+            match="got an unexpected keyword argument 'missing_arg'"):
+        func(2, **{missing_arg: 3})
+

.venv/lib/python3.11/site-packages/numpy/core/tests/test_array_coercion.py

@@ -0,0 +1,898 @@
+"""
+Tests for array coercion, mainly through testing `np.array` results directly.
+Note that other such tests exist, e.g., in `test_api.py` and many corner-cases
+are tested (sometimes indirectly) elsewhere.
+"""
+
+from itertools import permutations, product
+
+import pytest
+from pytest import param
+
+import numpy as np
+from numpy.core._rational_tests import rational
+from numpy.core._multiarray_umath import _discover_array_parameters
+
+from numpy.testing import (
+    assert_array_equal, assert_warns, IS_PYPY)
+
+
+def arraylikes():
+    """
+    Generator for functions converting an array into various array-likes.
+    If full is True (default) it includes array-likes not capable of handling
+    all dtypes.
+    """
+    # base array:
+    def ndarray(a):
+        return a
+
+    yield param(ndarray, id="ndarray")
+
+    # subclass:
+    class MyArr(np.ndarray):
+        pass
+
+    def subclass(a):
+        return a.view(MyArr)
+
+    yield subclass
+
+    class _SequenceLike():
+        # Older NumPy versions, sometimes cared whether a protocol array was
+        # also _SequenceLike.  This shouldn't matter, but keep it for now
+        # for __array__ and not the others.
+        def __len__(self):
+            raise TypeError
+
+        def __getitem__(self):
+            raise TypeError
+
+    # Array-interface
+    class ArrayDunder(_SequenceLike):
+        def __init__(self, a):
+            self.a = a
+
+        def __array__(self, dtype=None):
+            return self.a
+
+    yield param(ArrayDunder, id="__array__")
+
+    # memory-view
+    yield param(memoryview, id="memoryview")
+
+    # Array-interface
+    class ArrayInterface:
+        def __init__(self, a):
+            self.a = a  # need to hold on to keep interface valid
+            self.__array_interface__ = a.__array_interface__
+
+    yield param(ArrayInterface, id="__array_interface__")
+
+    # Array-Struct
+    class ArrayStruct:
+        def __init__(self, a):
+            self.a = a  # need to hold on to keep struct valid
+            self.__array_struct__ = a.__array_struct__
+
+    yield param(ArrayStruct, id="__array_struct__")
+
+
+def scalar_instances(times=True, extended_precision=True, user_dtype=True):
+    # Hard-coded list of scalar instances.
+    # Floats:
+    yield param(np.sqrt(np.float16(5)), id="float16")
+    yield param(np.sqrt(np.float32(5)), id="float32")
+    yield param(np.sqrt(np.float64(5)), id="float64")
+    if extended_precision:
+        yield param(np.sqrt(np.longdouble(5)), id="longdouble")
+
+    # Complex:
+    yield param(np.sqrt(np.complex64(2+3j)), id="complex64")
+    yield param(np.sqrt(np.complex128(2+3j)), id="complex128")
+    if extended_precision:
+        yield param(np.sqrt(np.longcomplex(2+3j)), id="clongdouble")
+
+    # Bool:
+    # XFAIL: Bool should be added, but has some bad properties when it
+    # comes to strings, see also gh-9875
+    # yield param(np.bool_(0), id="bool")
+
+    # Integers:
+    yield param(np.int8(2), id="int8")
+    yield param(np.int16(2), id="int16")
+    yield param(np.int32(2), id="int32")
+    yield param(np.int64(2), id="int64")
+
+    yield param(np.uint8(2), id="uint8")
+    yield param(np.uint16(2), id="uint16")
+    yield param(np.uint32(2), id="uint32")
+    yield param(np.uint64(2), id="uint64")
+
+    # Rational:
+    if user_dtype:
+        yield param(rational(1, 2), id="rational")
+
+    # Cannot create a structured void scalar directly:
+    structured = np.array([(1, 3)], "i,i")[0]
+    assert isinstance(structured, np.void)
+    assert structured.dtype == np.dtype("i,i")
+    yield param(structured, id="structured")
+
+    if times:
+        # Datetimes and timedelta
+        yield param(np.timedelta64(2), id="timedelta64[generic]")
+        yield param(np.timedelta64(23, "s"), id="timedelta64[s]")
+        yield param(np.timedelta64("NaT", "s"), id="timedelta64[s](NaT)")
+
+        yield param(np.datetime64("NaT"), id="datetime64[generic](NaT)")
+        yield param(np.datetime64("2020-06-07 12:43", "ms"), id="datetime64[ms]")
+
+    # Strings and unstructured void:
+    yield param(np.bytes_(b"1234"), id="bytes")
+    yield param(np.str_("2345"), id="unicode")
+    yield param(np.void(b"4321"), id="unstructured_void")
+
+
+def is_parametric_dtype(dtype):
+    """Returns True if the dtype is a parametric legacy dtype (itemsize
+    is 0, or a datetime without units)
+    """
+    if dtype.itemsize == 0:
+        return True
+    if issubclass(dtype.type, (np.datetime64, np.timedelta64)):
+        if dtype.name.endswith("64"):
+            # Generic time units
+            return True
+    return False
+
+
+class TestStringDiscovery:
+    @pytest.mark.parametrize("obj",
+            [object(), 1.2, 10**43, None, "string"],
+            ids=["object", "1.2", "10**43", "None", "string"])
+    def test_basic_stringlength(self, obj):
+        length = len(str(obj))
+        expected = np.dtype(f"S{length}")
+
+        assert np.array(obj, dtype="S").dtype == expected
+        assert np.array([obj], dtype="S").dtype == expected
+
+        # A nested array is also discovered correctly
+        arr = np.array(obj, dtype="O")
+        assert np.array(arr, dtype="S").dtype == expected
+        # Also if we use the dtype class
+        assert np.array(arr, dtype=type(expected)).dtype == expected
+        # Check that .astype() behaves identical
+        assert arr.astype("S").dtype == expected
+        # The DType class is accepted by `.astype()`
+        assert arr.astype(type(np.dtype("S"))).dtype == expected
+
+    @pytest.mark.parametrize("obj",
+            [object(), 1.2, 10**43, None, "string"],
+            ids=["object", "1.2", "10**43", "None", "string"])
+    def test_nested_arrays_stringlength(self, obj):
+        length = len(str(obj))
+        expected = np.dtype(f"S{length}")
+        arr = np.array(obj, dtype="O")
+        assert np.array([arr, arr], dtype="S").dtype == expected
+
+    @pytest.mark.parametrize("arraylike", arraylikes())
+    def test_unpack_first_level(self, arraylike):
+        # We unpack exactly one level of array likes
+        obj = np.array([None])
+        obj[0] = np.array(1.2)
+        # the length of the included item, not of the float dtype
+        length = len(str(obj[0]))
+        expected = np.dtype(f"S{length}")
+
+        obj = arraylike(obj)
+        # casting to string usually calls str(obj)
+        arr = np.array([obj], dtype="S")
+        assert arr.shape == (1, 1)
+        assert arr.dtype == expected
+
+
+class TestScalarDiscovery:
+    def test_void_special_case(self):
+        # Void dtypes with structures discover tuples as elements
+        arr = np.array((1, 2, 3), dtype="i,i,i")
+        assert arr.shape == ()
+        arr = np.array([(1, 2, 3)], dtype="i,i,i")
+        assert arr.shape == (1,)
+
+    def test_char_special_case(self):
+        arr = np.array("string", dtype="c")
+        assert arr.shape == (6,)
+        assert arr.dtype.char == "c"
+        arr = np.array(["string"], dtype="c")
+        assert arr.shape == (1, 6)
+        assert arr.dtype.char == "c"
+
+    def test_char_special_case_deep(self):
+        # Check that the character special case errors correctly if the
+        # array is too deep:
+        nested = ["string"]  # 2 dimensions (due to string being sequence)
+        for i in range(np.MAXDIMS - 2):
+            nested = [nested]
+
+        arr = np.array(nested, dtype='c')
+        assert arr.shape == (1,) * (np.MAXDIMS - 1) + (6,)
+        with pytest.raises(ValueError):
+            np.array([nested], dtype="c")
+
+    def test_unknown_object(self):
+        arr = np.array(object())
+        assert arr.shape == ()
+        assert arr.dtype == np.dtype("O")
+
+    @pytest.mark.parametrize("scalar", scalar_instances())
+    def test_scalar(self, scalar):
+        arr = np.array(scalar)
+        assert arr.shape == ()
+        assert arr.dtype == scalar.dtype
+
+        arr = np.array([[scalar, scalar]])
+        assert arr.shape == (1, 2)
+        assert arr.dtype == scalar.dtype
+
+    # Additionally to string this test also runs into a corner case
+    # with datetime promotion (the difference is the promotion order).
+    @pytest.mark.filterwarnings("ignore:Promotion of numbers:FutureWarning")
+    def test_scalar_promotion(self):
+        for sc1, sc2 in product(scalar_instances(), scalar_instances()):
+            sc1, sc2 = sc1.values[0], sc2.values[0]
+            # test all combinations:
+            try:
+                arr = np.array([sc1, sc2])
+            except (TypeError, ValueError):
+                # The promotion between two times can fail
+                # XFAIL (ValueError): Some object casts are currently undefined
+                continue
+            assert arr.shape == (2,)
+            try:
+                dt1, dt2 = sc1.dtype, sc2.dtype
+                expected_dtype = np.promote_types(dt1, dt2)
+                assert arr.dtype == expected_dtype
+            except TypeError as e:
+                # Will currently always go to object dtype
+                assert arr.dtype == np.dtype("O")
+
+    @pytest.mark.parametrize("scalar", scalar_instances())
+    def test_scalar_coercion(self, scalar):
+        # This tests various scalar coercion paths, mainly for the numerical
+        # types. It includes some paths not directly related to `np.array`.
+        if isinstance(scalar, np.inexact):
+            # Ensure we have a full-precision number if available
+            scalar = type(scalar)((scalar * 2)**0.5)
+
+        if type(scalar) is rational:
+            # Rational generally fails due to a missing cast. In the future
+            # object casts should automatically be defined based on `setitem`.
+            pytest.xfail("Rational to object cast is undefined currently.")
+
+        # Use casting from object:
+        arr = np.array(scalar, dtype=object).astype(scalar.dtype)
+
+        # Test various ways to create an array containing this scalar:
+        arr1 = np.array(scalar).reshape(1)
+        arr2 = np.array([scalar])
+        arr3 = np.empty(1, dtype=scalar.dtype)
+        arr3[0] = scalar
+        arr4 = np.empty(1, dtype=scalar.dtype)
+        arr4[:] = [scalar]
+        # All of these methods should yield the same results
+        assert_array_equal(arr, arr1)
+        assert_array_equal(arr, arr2)
+        assert_array_equal(arr, arr3)
+        assert_array_equal(arr, arr4)
+
+    @pytest.mark.xfail(IS_PYPY, reason="`int(np.complex128(3))` fails on PyPy")
+    @pytest.mark.filterwarnings("ignore::numpy.ComplexWarning")
+    @pytest.mark.parametrize("cast_to", scalar_instances())
+    def test_scalar_coercion_same_as_cast_and_assignment(self, cast_to):
+        """
+        Test that in most cases:
+           * `np.array(scalar, dtype=dtype)`
+           * `np.empty((), dtype=dtype)[()] = scalar`
+           * `np.array(scalar).astype(dtype)`
+        should behave the same.  The only exceptions are parametric dtypes
+        (mainly datetime/timedelta without unit) and void without fields.
+        """
+        dtype = cast_to.dtype  # use to parametrize only the target dtype
+
+        for scalar in scalar_instances(times=False):
+            scalar = scalar.values[0]
+
+            if dtype.type == np.void:
+               if scalar.dtype.fields is not None and dtype.fields is None:
+                    # Here, coercion to "V6" works, but the cast fails.
+                    # Since the types are identical, SETITEM takes care of
+                    # this, but has different rules than the cast.
+                    with pytest.raises(TypeError):
+                        np.array(scalar).astype(dtype)
+                    np.array(scalar, dtype=dtype)
+                    np.array([scalar], dtype=dtype)
+                    continue
+
+            # The main test, we first try to use casting and if it succeeds
+            # continue below testing that things are the same, otherwise
+            # test that the alternative paths at least also fail.
+            try:
+                cast = np.array(scalar).astype(dtype)
+            except (TypeError, ValueError, RuntimeError):
+                # coercion should also raise (error type may change)
+                with pytest.raises(Exception):
+                    np.array(scalar, dtype=dtype)
+
+                if (isinstance(scalar, rational) and
+                        np.issubdtype(dtype, np.signedinteger)):
+                    return
+
+                with pytest.raises(Exception):
+                    np.array([scalar], dtype=dtype)
+                # assignment should also raise
+                res = np.zeros((), dtype=dtype)
+                with pytest.raises(Exception):
+                    res[()] = scalar
+
+                return
+
+            # Non error path:
+            arr = np.array(scalar, dtype=dtype)
+            assert_array_equal(arr, cast)
+            # assignment behaves the same
+            ass = np.zeros((), dtype=dtype)
+            ass[()] = scalar
+            assert_array_equal(ass, cast)
+
+    @pytest.mark.parametrize("pyscalar", [10, 10.32, 10.14j, 10**100])
+    def test_pyscalar_subclasses(self, pyscalar):
+        """NumPy arrays are read/write which means that anything but invariant
+        behaviour is on thin ice.  However, we currently are happy to discover
+        subclasses of Python float, int, complex the same as the base classes.
+        This should potentially be deprecated.
+        """
+        class MyScalar(type(pyscalar)):
+            pass
+
+        res = np.array(MyScalar(pyscalar))
+        expected = np.array(pyscalar)
+        assert_array_equal(res, expected)
+
+    @pytest.mark.parametrize("dtype_char", np.typecodes["All"])
+    def test_default_dtype_instance(self, dtype_char):
+        if dtype_char in "SU":
+            dtype = np.dtype(dtype_char + "1")
+        elif dtype_char == "V":
+            # Legacy behaviour was to use V8. The reason was float64 being the
+            # default dtype and that having 8 bytes.
+            dtype = np.dtype("V8")
+        else:
+            dtype = np.dtype(dtype_char)
+
+        discovered_dtype, _ = _discover_array_parameters([], type(dtype))
+
+        assert discovered_dtype == dtype
+        assert discovered_dtype.itemsize == dtype.itemsize
+
+    @pytest.mark.parametrize("dtype", np.typecodes["Integer"])
+    @pytest.mark.parametrize(["scalar", "error"],
+            [(np.float64(np.nan), ValueError),
+             (np.array(-1).astype(np.ulonglong)[()], OverflowError)])
+    def test_scalar_to_int_coerce_does_not_cast(self, dtype, scalar, error):
+        """
+        Signed integers are currently different in that they do not cast other
+        NumPy scalar, but instead use scalar.__int__(). The hardcoded
+        exception to this rule is `np.array(scalar, dtype=integer)`.
+        """
+        dtype = np.dtype(dtype)
+
+        # This is a special case using casting logic. It warns for the NaN
+        # but allows the cast (giving undefined behaviour).
+        with np.errstate(invalid="ignore"):
+            coerced = np.array(scalar, dtype=dtype)
+            cast = np.array(scalar).astype(dtype)
+        assert_array_equal(coerced, cast)
+
+        # However these fail:
+        with pytest.raises(error):
+            np.array([scalar], dtype=dtype)
+        with pytest.raises(error):
+            cast[()] = scalar
+
+
+class TestTimeScalars:
+    @pytest.mark.parametrize("dtype", [np.int64, np.float32])
+    @pytest.mark.parametrize("scalar",
+            [param(np.timedelta64("NaT", "s"), id="timedelta64[s](NaT)"),
+             param(np.timedelta64(123, "s"), id="timedelta64[s]"),
+             param(np.datetime64("NaT", "generic"), id="datetime64[generic](NaT)"),
+             param(np.datetime64(1, "D"), id="datetime64[D]")],)
+    def test_coercion_basic(self, dtype, scalar):
+        # Note the `[scalar]` is there because np.array(scalar) uses stricter
+        # `scalar.__int__()` rules for backward compatibility right now.
+        arr = np.array(scalar, dtype=dtype)
+        cast = np.array(scalar).astype(dtype)
+        assert_array_equal(arr, cast)
+
+        ass = np.ones((), dtype=dtype)
+        if issubclass(dtype, np.integer):
+            with pytest.raises(TypeError):
+                # raises, as would np.array([scalar], dtype=dtype), this is
+                # conversion from times, but behaviour of integers.
+                ass[()] = scalar
+        else:
+            ass[()] = scalar
+            assert_array_equal(ass, cast)
+
+    @pytest.mark.parametrize("dtype", [np.int64, np.float32])
+    @pytest.mark.parametrize("scalar",
+            [param(np.timedelta64(123, "ns"), id="timedelta64[ns]"),
+             param(np.timedelta64(12, "generic"), id="timedelta64[generic]")])
+    def test_coercion_timedelta_convert_to_number(self, dtype, scalar):
+        # Only "ns" and "generic" timedeltas can be converted to numbers
+        # so these are slightly special.
+        arr = np.array(scalar, dtype=dtype)
+        cast = np.array(scalar).astype(dtype)
+        ass = np.ones((), dtype=dtype)
+        ass[()] = scalar  # raises, as would np.array([scalar], dtype=dtype)
+
+        assert_array_equal(arr, cast)
+        assert_array_equal(cast, cast)
+
+    @pytest.mark.parametrize("dtype", ["S6", "U6"])
+    @pytest.mark.parametrize(["val", "unit"],
+            [param(123, "s", id="[s]"), param(123, "D", id="[D]")])
+    def test_coercion_assignment_datetime(self, val, unit, dtype):
+        # String from datetime64 assignment is currently special cased to
+        # never use casting.  This is because casting will error in this
+        # case, and traditionally in most cases the behaviour is maintained
+        # like this.  (`np.array(scalar, dtype="U6")` would have failed before)
+        # TODO: This discrepancy _should_ be resolved, either by relaxing the
+        #       cast, or by deprecating the first part.
+        scalar = np.datetime64(val, unit)
+        dtype = np.dtype(dtype)
+        cut_string = dtype.type(str(scalar)[:6])
+
+        arr = np.array(scalar, dtype=dtype)
+        assert arr[()] == cut_string
+        ass = np.ones((), dtype=dtype)
+        ass[()] = scalar
+        assert ass[()] == cut_string
+
+        with pytest.raises(RuntimeError):
+            # However, unlike the above assignment using `str(scalar)[:6]`
+            # due to being handled by the string DType and not be casting
+            # the explicit cast fails:
+            np.array(scalar).astype(dtype)
+
+
+    @pytest.mark.parametrize(["val", "unit"],
+            [param(123, "s", id="[s]"), param(123, "D", id="[D]")])
+    def test_coercion_assignment_timedelta(self, val, unit):
+        scalar = np.timedelta64(val, unit)
+
+        # Unlike datetime64, timedelta allows the unsafe cast:
+        np.array(scalar, dtype="S6")
+        cast = np.array(scalar).astype("S6")
+        ass = np.ones((), dtype="S6")
+        ass[()] = scalar
+        expected = scalar.astype("S")[:6]
+        assert cast[()] == expected
+        assert ass[()] == expected
+
+class TestNested:
+    def test_nested_simple(self):
+        initial = [1.2]
+        nested = initial
+        for i in range(np.MAXDIMS - 1):
+            nested = [nested]
+
+        arr = np.array(nested, dtype="float64")
+        assert arr.shape == (1,) * np.MAXDIMS
+        with pytest.raises(ValueError):
+            np.array([nested], dtype="float64")
+
+        with pytest.raises(ValueError, match=".*would exceed the maximum"):
+            np.array([nested])  # user must ask for `object` explicitly
+
+        arr = np.array([nested], dtype=object)
+        assert arr.dtype == np.dtype("O")
+        assert arr.shape == (1,) * np.MAXDIMS
+        assert arr.item() is initial
+
+    def test_pathological_self_containing(self):
+        # Test that this also works for two nested sequences
+        l = []
+        l.append(l)
+        arr = np.array([l, l, l], dtype=object)
+        assert arr.shape == (3,) + (1,) * (np.MAXDIMS - 1)
+
+        # Also check a ragged case:
+        arr = np.array([l, [None], l], dtype=object)
+        assert arr.shape == (3, 1)
+
+    @pytest.mark.parametrize("arraylike", arraylikes())
+    def test_nested_arraylikes(self, arraylike):
+        # We try storing an array like into an array, but the array-like
+        # will have too many dimensions.  This means the shape discovery
+        # decides that the array-like must be treated as an object (a special
+        # case of ragged discovery).  The result will be an array with one
+        # dimension less than the maximum dimensions, and the array being
+        # assigned to it (which does work for object or if `float(arraylike)`
+        # works).
+        initial = arraylike(np.ones((1, 1)))
+
+        nested = initial
+        for i in range(np.MAXDIMS - 1):
+            nested = [nested]
+
+        with pytest.raises(ValueError, match=".*would exceed the maximum"):
+            # It will refuse to assign the array into
+            np.array(nested, dtype="float64")
+
+        # If this is object, we end up assigning a (1, 1) array into (1,)
+        # (due to running out of dimensions), this is currently supported but
+        # a special case which is not ideal.
+        arr = np.array(nested, dtype=object)
+        assert arr.shape == (1,) * np.MAXDIMS
+        assert arr.item() == np.array(initial).item()
+
+    @pytest.mark.parametrize("arraylike", arraylikes())
+    def test_uneven_depth_ragged(self, arraylike):
+        arr = np.arange(4).reshape((2, 2))
+        arr = arraylike(arr)
+
+        # Array is ragged in the second dimension already:
+        out = np.array([arr, [arr]], dtype=object)
+        assert out.shape == (2,)
+        assert out[0] is arr
+        assert type(out[1]) is list
+
+        # Array is ragged in the third dimension:
+        with pytest.raises(ValueError):
+            # This is a broadcast error during assignment, because
+            # the array shape would be (2, 2, 2) but `arr[0, 0] = arr` fails.
+            np.array([arr, [arr, arr]], dtype=object)
+
+    def test_empty_sequence(self):
+        arr = np.array([[], [1], [[1]]], dtype=object)
+        assert arr.shape == (3,)
+
+        # The empty sequence stops further dimension discovery, so the
+        # result shape will be (0,) which leads to an error during:
+        with pytest.raises(ValueError):
+            np.array([[], np.empty((0, 1))], dtype=object)
+
+    def test_array_of_different_depths(self):
+        # When multiple arrays (or array-likes) are included in a
+        # sequences and have different depth, we currently discover
+        # as many dimensions as they share. (see also gh-17224)
+        arr = np.zeros((3, 2))
+        mismatch_first_dim = np.zeros((1, 2))
+        mismatch_second_dim = np.zeros((3, 3))
+
+        dtype, shape = _discover_array_parameters(
+            [arr, mismatch_second_dim], dtype=np.dtype("O"))
+        assert shape == (2, 3)
+
+        dtype, shape = _discover_array_parameters(
+            [arr, mismatch_first_dim], dtype=np.dtype("O"))
+        assert shape == (2,)
+        # The second case is currently supported because the arrays
+        # can be stored as objects:
+        res = np.asarray([arr, mismatch_first_dim], dtype=np.dtype("O"))
+        assert res[0] is arr
+        assert res[1] is mismatch_first_dim
+
+
+class TestBadSequences:
+    # These are tests for bad objects passed into `np.array`, in general
+    # these have undefined behaviour.  In the old code they partially worked
+    # when now they will fail.  We could (and maybe should) create a copy
+    # of all sequences to be safe against bad-actors.
+
+    def test_growing_list(self):
+        # List to coerce, `mylist` will append to it during coercion
+        obj = []
+        class mylist(list):
+            def __len__(self):
+                obj.append([1, 2])
+                return super().__len__()
+
+        obj.append(mylist([1, 2]))
+
+        with pytest.raises(RuntimeError):
+            np.array(obj)
+
+    # Note: We do not test a shrinking list.  These do very evil things
+    #       and the only way to fix them would be to copy all sequences.
+    #       (which may be a real option in the future).
+
+    def test_mutated_list(self):
+        # List to coerce, `mylist` will mutate the first element
+        obj = []
+        class mylist(list):
+            def __len__(self):
+                obj[0] = [2, 3]  # replace with a different list.
+                return super().__len__()
+
+        obj.append([2, 3])
+        obj.append(mylist([1, 2]))
+        # Does not crash:
+        np.array(obj)
+
+    def test_replace_0d_array(self):
+        # List to coerce, `mylist` will mutate the first element
+        obj = []
+        class baditem:
+            def __len__(self):
+                obj[0][0] = 2  # replace with a different list.
+                raise ValueError("not actually a sequence!")
+
+            def __getitem__(self):
+                pass
+
+        # Runs into a corner case in the new code, the `array(2)` is cached
+        # so replacing it invalidates the cache.
+        obj.append([np.array(2), baditem()])
+        with pytest.raises(RuntimeError):
+            np.array(obj)
+
+
+class TestArrayLikes:
+    @pytest.mark.parametrize("arraylike", arraylikes())
+    def test_0d_object_special_case(self, arraylike):
+        arr = np.array(0.)
+        obj = arraylike(arr)
+        # A single array-like is always converted:
+        res = np.array(obj, dtype=object)
+        assert_array_equal(arr, res)
+
+        # But a single 0-D nested array-like never:
+        res = np.array([obj], dtype=object)
+        assert res[0] is obj
+
+    @pytest.mark.parametrize("arraylike", arraylikes())
+    @pytest.mark.parametrize("arr", [np.array(0.), np.arange(4)])
+    def test_object_assignment_special_case(self, arraylike, arr):
+        obj = arraylike(arr)
+        empty = np.arange(1, dtype=object)
+        empty[:] = [obj]
+        assert empty[0] is obj
+
+    def test_0d_generic_special_case(self):
+        class ArraySubclass(np.ndarray):
+            def __float__(self):
+                raise TypeError("e.g. quantities raise on this")
+
+        arr = np.array(0.)
+        obj = arr.view(ArraySubclass)
+        res = np.array(obj)
+        # The subclass is simply cast:
+        assert_array_equal(arr, res)
+
+        # If the 0-D array-like is included, __float__ is currently
+        # guaranteed to be used.  We may want to change that, quantities
+        # and masked arrays half make use of this.
+        with pytest.raises(TypeError):
+            np.array([obj])
+
+        # The same holds for memoryview:
+        obj = memoryview(arr)
+        res = np.array(obj)
+        assert_array_equal(arr, res)
+        with pytest.raises(ValueError):
+            # The error type does not matter much here.
+            np.array([obj])
+
+    def test_arraylike_classes(self):
+        # The classes of array-likes should generally be acceptable to be
+        # stored inside a numpy (object) array.  This tests all of the
+        # special attributes (since all are checked during coercion).
+        arr = np.array(np.int64)
+        assert arr[()] is np.int64
+        arr = np.array([np.int64])
+        assert arr[0] is np.int64
+
+        # This also works for properties/unbound methods:
+        class ArrayLike:
+            @property
+            def __array_interface__(self):
+                pass
+
+            @property
+            def __array_struct__(self):
+                pass
+
+            def __array__(self):
+                pass
+
+        arr = np.array(ArrayLike)
+        assert arr[()] is ArrayLike
+        arr = np.array([ArrayLike])
+        assert arr[0] is ArrayLike
+
+    @pytest.mark.skipif(
+            np.dtype(np.intp).itemsize < 8, reason="Needs 64bit platform")
+    def test_too_large_array_error_paths(self):
+        """Test the error paths, including for memory leaks"""
+        arr = np.array(0, dtype="uint8")
+        # Guarantees that a contiguous copy won't work:
+        arr = np.broadcast_to(arr, 2**62)
+
+        for i in range(5):
+            # repeat, to ensure caching cannot have an effect:
+            with pytest.raises(MemoryError):
+                np.array(arr)
+            with pytest.raises(MemoryError):
+                np.array([arr])
+
+    @pytest.mark.parametrize("attribute",
+        ["__array_interface__", "__array__", "__array_struct__"])
+    @pytest.mark.parametrize("error", [RecursionError, MemoryError])
+    def test_bad_array_like_attributes(self, attribute, error):
+        # RecursionError and MemoryError are considered fatal. All errors
+        # (except AttributeError) should probably be raised in the future,
+        # but shapely made use of it, so it will require a deprecation.
+
+        class BadInterface:
+            def __getattr__(self, attr):
+                if attr == attribute:
+                    raise error
+                super().__getattr__(attr)
+
+        with pytest.raises(error):
+            np.array(BadInterface())
+
+    @pytest.mark.parametrize("error", [RecursionError, MemoryError])
+    def test_bad_array_like_bad_length(self, error):
+        # RecursionError and MemoryError are considered "critical" in
+        # sequences. We could expand this more generally though. (NumPy 1.20)
+        class BadSequence:
+            def __len__(self):
+                raise error
+            def __getitem__(self):
+                # must have getitem to be a Sequence
+                return 1
+
+        with pytest.raises(error):
+            np.array(BadSequence())
+
+
+class TestAsArray:
+    """Test expected behaviors of ``asarray``."""
+
+    def test_dtype_identity(self):
+        """Confirm the intended behavior for *dtype* kwarg.
+
+        The result of ``asarray()`` should have the dtype provided through the
+        keyword argument, when used. This forces unique array handles to be
+        produced for unique np.dtype objects, but (for equivalent dtypes), the
+        underlying data (the base object) is shared with the original array
+        object.
+
+        Ref https://github.com/numpy/numpy/issues/1468
+        """
+        int_array = np.array([1, 2, 3], dtype='i')
+        assert np.asarray(int_array) is int_array
+
+        # The character code resolves to the singleton dtype object provided
+        # by the numpy package.
+        assert np.asarray(int_array, dtype='i') is int_array
+
+        # Derive a dtype from n.dtype('i'), but add a metadata object to force
+        # the dtype to be distinct.
+        unequal_type = np.dtype('i', metadata={'spam': True})
+        annotated_int_array = np.asarray(int_array, dtype=unequal_type)
+        assert annotated_int_array is not int_array
+        assert annotated_int_array.base is int_array
+        # Create an equivalent descriptor with a new and distinct dtype
+        # instance.
+        equivalent_requirement = np.dtype('i', metadata={'spam': True})
+        annotated_int_array_alt = np.asarray(annotated_int_array,
+                                             dtype=equivalent_requirement)
+        assert unequal_type == equivalent_requirement
+        assert unequal_type is not equivalent_requirement
+        assert annotated_int_array_alt is not annotated_int_array
+        assert annotated_int_array_alt.dtype is equivalent_requirement
+
+        # Check the same logic for a pair of C types whose equivalence may vary
+        # between computing environments.
+        # Find an equivalent pair.
+        integer_type_codes = ('i', 'l', 'q')
+        integer_dtypes = [np.dtype(code) for code in integer_type_codes]
+        typeA = None
+        typeB = None
+        for typeA, typeB in permutations(integer_dtypes, r=2):
+            if typeA == typeB:
+                assert typeA is not typeB
+                break
+        assert isinstance(typeA, np.dtype) and isinstance(typeB, np.dtype)
+
+        # These ``asarray()`` calls may produce a new view or a copy,
+        # but never the same object.
+        long_int_array = np.asarray(int_array, dtype='l')
+        long_long_int_array = np.asarray(int_array, dtype='q')
+        assert long_int_array is not int_array
+        assert long_long_int_array is not int_array
+        assert np.asarray(long_int_array, dtype='q') is not long_int_array
+        array_a = np.asarray(int_array, dtype=typeA)
+        assert typeA == typeB
+        assert typeA is not typeB
+        assert array_a.dtype is typeA
+        assert array_a is not np.asarray(array_a, dtype=typeB)
+        assert np.asarray(array_a, dtype=typeB).dtype is typeB
+        assert array_a is np.asarray(array_a, dtype=typeB).base
+
+
+class TestSpecialAttributeLookupFailure:
+    # An exception was raised while fetching the attribute
+
+    class WeirdArrayLike:
+        @property
+        def __array__(self):
+            raise RuntimeError("oops!")
+
+    class WeirdArrayInterface:
+        @property
+        def __array_interface__(self):
+            raise RuntimeError("oops!")
+
+    def test_deprecated(self):
+        with pytest.raises(RuntimeError):
+            np.array(self.WeirdArrayLike())
+        with pytest.raises(RuntimeError):
+            np.array(self.WeirdArrayInterface())
+
+
+def test_subarray_from_array_construction():
+    # Arrays are more complex, since they "broadcast" on success:
+    arr = np.array([1, 2])
+
+    res = arr.astype("(2)i,")
+    assert_array_equal(res, [[1, 1], [2, 2]])
+
+    res = np.array(arr, dtype="(2)i,")
+
+    assert_array_equal(res, [[1, 1], [2, 2]])
+
+    res = np.array([[(1,), (2,)], arr], dtype="(2)i,")
+    assert_array_equal(res, [[[1, 1], [2, 2]], [[1, 1], [2, 2]]])
+
+    # Also try a multi-dimensional example:
+    arr = np.arange(5 * 2).reshape(5, 2)
+    expected = np.broadcast_to(arr[:, :, np.newaxis, np.newaxis], (5, 2, 2, 2))
+
+    res = arr.astype("(2,2)f")
+    assert_array_equal(res, expected)
+
+    res = np.array(arr, dtype="(2,2)f")
+    assert_array_equal(res, expected)
+
+
+def test_empty_string():
+    # Empty strings are unfortunately often converted to S1 and we need to
+    # make sure we are filling the S1 and not the (possibly) detected S0
+    # result.  This should likely just return S0 and if not maybe the decision
+    # to return S1 should be moved.
+    res = np.array([""] * 10, dtype="S")
+    assert_array_equal(res, np.array("\0", "S1"))
+    assert res.dtype == "S1"
+
+    arr = np.array([""] * 10, dtype=object)
+
+    res = arr.astype("S")
+    assert_array_equal(res, b"")
+    assert res.dtype == "S1"
+
+    res = np.array(arr, dtype="S")
+    assert_array_equal(res, b"")
+    # TODO: This is arguably weird/wrong, but seems old:
+    assert res.dtype == f"S{np.dtype('O').itemsize}"
+
+    res = np.array([[""] * 10, arr], dtype="S")
+    assert_array_equal(res, b"")
+    assert res.shape == (2, 10)
+    assert res.dtype == "S1"

.venv/lib/python3.11/site-packages/numpy/core/tests/test_array_interface.py

@@ -0,0 +1,219 @@
+import sys
+import pytest
+import numpy as np
+from numpy.testing import extbuild
+
+
+@pytest.fixture
+def get_module(tmp_path):
+    """ Some codes to generate data and manage temporary buffers use when
+    sharing with numpy via the array interface protocol.
+    """
+
+    if not sys.platform.startswith('linux'):
+        pytest.skip('link fails on cygwin')
+
+    prologue = '''
+        #include <Python.h>
+        #define NPY_NO_DEPRECATED_API NPY_1_7_API_VERSION
+        #include <numpy/arrayobject.h>
+        #include <stdio.h>
+        #include <math.h>
+
+        NPY_NO_EXPORT
+        void delete_array_struct(PyObject *cap) {
+
+            /* get the array interface structure */
+            PyArrayInterface *inter = (PyArrayInterface*)
+                PyCapsule_GetPointer(cap, NULL);
+
+            /* get the buffer by which data was shared */
+            double *ptr = (double*)PyCapsule_GetContext(cap);
+
+            /* for the purposes of the regression test set the elements
+               to nan */
+            for (npy_intp i = 0; i < inter->shape[0]; ++i)
+                ptr[i] = nan("");
+
+            /* free the shared buffer */
+            free(ptr);
+
+            /* free the array interface structure */
+            free(inter->shape);
+            free(inter);
+
+            fprintf(stderr, "delete_array_struct\\ncap = %ld inter = %ld"
+                " ptr = %ld\\n", (long)cap, (long)inter, (long)ptr);
+        }
+        '''
+
+    functions = [
+        ("new_array_struct", "METH_VARARGS", """
+
+            long long n_elem = 0;
+            double value = 0.0;
+
+            if (!PyArg_ParseTuple(args, "Ld", &n_elem, &value)) {
+                Py_RETURN_NONE;
+            }
+
+            /* allocate and initialize the data to share with numpy */
+            long long n_bytes = n_elem*sizeof(double);
+            double *data = (double*)malloc(n_bytes);
+
+            if (!data) {
+                PyErr_Format(PyExc_MemoryError,
+                    "Failed to malloc %lld bytes", n_bytes);
+
+                Py_RETURN_NONE;
+            }
+
+            for (long long i = 0; i < n_elem; ++i) {
+                data[i] = value;
+            }
+
+            /* calculate the shape and stride */
+            int nd = 1;
+
+            npy_intp *ss = (npy_intp*)malloc(2*nd*sizeof(npy_intp));
+            npy_intp *shape = ss;
+            npy_intp *stride = ss + nd;
+
+            shape[0] = n_elem;
+            stride[0] = sizeof(double);
+
+            /* construct the array interface */
+            PyArrayInterface *inter = (PyArrayInterface*)
+                malloc(sizeof(PyArrayInterface));
+
+            memset(inter, 0, sizeof(PyArrayInterface));
+
+            inter->two = 2;
+            inter->nd = nd;
+            inter->typekind = 'f';
+            inter->itemsize = sizeof(double);
+            inter->shape = shape;
+            inter->strides = stride;
+            inter->data = data;
+            inter->flags = NPY_ARRAY_WRITEABLE | NPY_ARRAY_NOTSWAPPED |
+                           NPY_ARRAY_ALIGNED | NPY_ARRAY_C_CONTIGUOUS;
+
+            /* package into a capsule */
+            PyObject *cap = PyCapsule_New(inter, NULL, delete_array_struct);
+
+            /* save the pointer to the data */
+            PyCapsule_SetContext(cap, data);
+
+            fprintf(stderr, "new_array_struct\\ncap = %ld inter = %ld"
+                " ptr = %ld\\n", (long)cap, (long)inter, (long)data);
+
+            return cap;
+        """)
+        ]
+
+    more_init = "import_array();"
+
+    try:
+        import array_interface_testing
+        return array_interface_testing
+    except ImportError:
+        pass
+
+    # if it does not exist, build and load it
+    return extbuild.build_and_import_extension('array_interface_testing',
+                                               functions,
+                                               prologue=prologue,
+                                               include_dirs=[np.get_include()],
+                                               build_dir=tmp_path,
+                                               more_init=more_init)
+
+
+# FIXME: numpy.testing.extbuild uses `numpy.distutils`, so this won't work on
+# Python 3.12 and up.
+@pytest.mark.skipif(sys.version_info >= (3, 12), reason="no numpy.distutils")
+@pytest.mark.slow
+def test_cstruct(get_module):
+
+    class data_source:
+        """
+        This class is for testing the timing of the PyCapsule destructor
+        invoked when numpy release its reference to the shared data as part of
+        the numpy array interface protocol. If the PyCapsule destructor is
+        called early the shared data is freed and invalid memory accesses will
+        occur.
+        """
+
+        def __init__(self, size, value):
+            self.size = size
+            self.value = value
+
+        @property
+        def __array_struct__(self):
+            return get_module.new_array_struct(self.size, self.value)
+
+    # write to the same stream as the C code
+    stderr = sys.__stderr__
+
+    # used to validate the shared data.
+    expected_value = -3.1415
+    multiplier = -10000.0
+
+    # create some data to share with numpy via the array interface
+    # assign the data an expected value.
+    stderr.write(' ---- create an object to share data ---- \n')
+    buf = data_source(256, expected_value)
+    stderr.write(' ---- OK!\n\n')
+
+    # share the data
+    stderr.write(' ---- share data via the array interface protocol ---- \n')
+    arr = np.array(buf, copy=False)
+    stderr.write('arr.__array_interface___ = %s\n' % (
+                 str(arr.__array_interface__)))
+    stderr.write('arr.base = %s\n' % (str(arr.base)))
+    stderr.write(' ---- OK!\n\n')
+
+    # release the source of the shared data. this will not release the data
+    # that was shared with numpy, that is done in the PyCapsule destructor.
+    stderr.write(' ---- destroy the object that shared data ---- \n')
+    buf = None
+    stderr.write(' ---- OK!\n\n')
+
+    # check that we got the expected data. If the PyCapsule destructor we
+    # defined was prematurely called then this test will fail because our
+    # destructor sets the elements of the array to NaN before free'ing the
+    # buffer. Reading the values here may also cause a SEGV
+    assert np.allclose(arr, expected_value)
+
+    # read the data. If the PyCapsule destructor we defined was prematurely
+    # called then reading the values here may cause a SEGV and will be reported
+    # as invalid reads by valgrind
+    stderr.write(' ---- read shared data ---- \n')
+    stderr.write('arr = %s\n' % (str(arr)))
+    stderr.write(' ---- OK!\n\n')
+
+    # write to the shared buffer. If the shared data was prematurely deleted
+    # this will may cause a SEGV and valgrind will report invalid writes
+    stderr.write(' ---- modify shared data ---- \n')
+    arr *= multiplier
+    expected_value *= multiplier
+    stderr.write('arr.__array_interface___ = %s\n' % (
+                 str(arr.__array_interface__)))
+    stderr.write('arr.base = %s\n' % (str(arr.base)))
+    stderr.write(' ---- OK!\n\n')
+
+    # read the data. If the shared data was prematurely deleted this
+    # will may cause a SEGV and valgrind will report invalid reads
+    stderr.write(' ---- read modified shared data ---- \n')
+    stderr.write('arr = %s\n' % (str(arr)))
+    stderr.write(' ---- OK!\n\n')
+
+    # check that we got the expected data. If the PyCapsule destructor we
+    # defined was prematurely called then this test will fail because our
+    # destructor sets the elements of the array to NaN before free'ing the
+    # buffer. Reading the values here may also cause a SEGV
+    assert np.allclose(arr, expected_value)
+
+    # free the shared data, the PyCapsule destructor should run here
+    stderr.write(' ---- free shared data ---- \n')
+    arr = None
+    stderr.write(' ---- OK!\n\n')

.venv/lib/python3.11/site-packages/numpy/core/tests/test_arraymethod.py

@@ -0,0 +1,85 @@
+"""
+This file tests the generic aspects of ArrayMethod.  At the time of writing
+this is private API, but when added, public API may be added here.
+"""
+
+from __future__ import annotations
+
+import sys
+import types
+from typing import Any
+
+import pytest
+
+import numpy as np
+from numpy.core._multiarray_umath import _get_castingimpl as get_castingimpl
+
+
+class TestResolveDescriptors:
+    # Test mainly error paths of the resolve_descriptors function,
+    # note that the `casting_unittests` tests exercise this non-error paths.
+
+    # Casting implementations are the main/only current user:
+    method = get_castingimpl(type(np.dtype("d")), type(np.dtype("f")))
+
+    @pytest.mark.parametrize("args", [
+        (True,),  # Not a tuple.
+        ((None,)),  # Too few elements
+        ((None, None, None),),  # Too many
+        ((None, None),),  # Input dtype is None, which is invalid.
+        ((np.dtype("d"), True),),  # Output dtype is not a dtype
+        ((np.dtype("f"), None),),  # Input dtype does not match method
+    ])
+    def test_invalid_arguments(self, args):
+        with pytest.raises(TypeError):
+            self.method._resolve_descriptors(*args)
+
+
+class TestSimpleStridedCall:
+    # Test mainly error paths of the resolve_descriptors function,
+    # note that the `casting_unittests` tests exercise this non-error paths.
+
+    # Casting implementations are the main/only current user:
+    method = get_castingimpl(type(np.dtype("d")), type(np.dtype("f")))
+
+    @pytest.mark.parametrize(["args", "error"], [
+        ((True,), TypeError),  # Not a tuple
+        (((None,),), TypeError),  # Too few elements
+        ((None, None), TypeError),  # Inputs are not arrays.
+        (((None, None, None),), TypeError),  # Too many
+        (((np.arange(3), np.arange(3)),), TypeError),  # Incorrect dtypes
+        (((np.ones(3, dtype=">d"), np.ones(3, dtype="<f")),),
+         TypeError),  # Does not support byte-swapping
+        (((np.ones((2, 2), dtype="d"), np.ones((2, 2), dtype="f")),),
+         ValueError),  # not 1-D
+        (((np.ones(3, dtype="d"), np.ones(4, dtype="f")),),
+          ValueError),  # different length
+        (((np.frombuffer(b"\0x00"*3*2, dtype="d"),
+           np.frombuffer(b"\0x00"*3, dtype="f")),),
+         ValueError),  # output not writeable
+    ])
+    def test_invalid_arguments(self, args, error):
+        # This is private API, which may be modified freely
+        with pytest.raises(error):
+            self.method._simple_strided_call(*args)
+
+
+@pytest.mark.parametrize(
+    "cls", [np.ndarray, np.recarray, np.chararray, np.matrix, np.memmap]
+)
+class TestClassGetItem:
+    def test_class_getitem(self, cls: type[np.ndarray]) -> None:
+        """Test `ndarray.__class_getitem__`."""
+        alias = cls[Any, Any]
+        assert isinstance(alias, types.GenericAlias)
+        assert alias.__origin__ is cls
+
+    @pytest.mark.parametrize("arg_len", range(4))
+    def test_subscript_tup(self, cls: type[np.ndarray], arg_len: int) -> None:
+        arg_tup = (Any,) * arg_len
+        if arg_len in (1, 2):
+            assert cls[arg_tup]
+        else:
+            match = f"Too {'few' if arg_len == 0 else 'many'} arguments"
+            with pytest.raises(TypeError, match=match):
+                cls[arg_tup]

.venv/lib/python3.11/site-packages/numpy/core/tests/test_arrayprint.py

@@ -0,0 +1,1047 @@
+import sys
+import gc
+from hypothesis import given
+from hypothesis.extra import numpy as hynp
+import pytest
+
+import numpy as np
+from numpy.testing import (
+    assert_, assert_equal, assert_raises, assert_warns, HAS_REFCOUNT,
+    assert_raises_regex,
+    )
+from numpy.core.arrayprint import _typelessdata
+import textwrap
+
+class TestArrayRepr:
+    def test_nan_inf(self):
+        x = np.array([np.nan, np.inf])
+        assert_equal(repr(x), 'array([nan, inf])')
+
+    def test_subclass(self):
+        class sub(np.ndarray): pass
+
+        # one dimensional
+        x1d = np.array([1, 2]).view(sub)
+        assert_equal(repr(x1d), 'sub([1, 2])')
+
+        # two dimensional
+        x2d = np.array([[1, 2], [3, 4]]).view(sub)
+        assert_equal(repr(x2d),
+            'sub([[1, 2],\n'
+            '     [3, 4]])')
+
+        # two dimensional with flexible dtype
+        xstruct = np.ones((2,2), dtype=[('a', '<i4')]).view(sub)
+        assert_equal(repr(xstruct),
+            "sub([[(1,), (1,)],\n"
+            "     [(1,), (1,)]], dtype=[('a', '<i4')])"
+        )
+
+    @pytest.mark.xfail(reason="See gh-10544")
+    def test_object_subclass(self):
+        class sub(np.ndarray):
+            def __new__(cls, inp):
+                obj = np.asarray(inp).view(cls)
+                return obj
+
+            def __getitem__(self, ind):
+                ret = super().__getitem__(ind)
+                return sub(ret)
+
+        # test that object + subclass is OK:
+        x = sub([None, None])
+        assert_equal(repr(x), 'sub([None, None], dtype=object)')
+        assert_equal(str(x), '[None None]')
+
+        x = sub([None, sub([None, None])])
+        assert_equal(repr(x),
+            'sub([None, sub([None, None], dtype=object)], dtype=object)')
+        assert_equal(str(x), '[None sub([None, None], dtype=object)]')
+
+    def test_0d_object_subclass(self):
+        # make sure that subclasses which return 0ds instead
+        # of scalars don't cause infinite recursion in str
+        class sub(np.ndarray):
+            def __new__(cls, inp):
+                obj = np.asarray(inp).view(cls)
+                return obj
+
+            def __getitem__(self, ind):
+                ret = super().__getitem__(ind)
+                return sub(ret)
+
+        x = sub(1)
+        assert_equal(repr(x), 'sub(1)')
+        assert_equal(str(x), '1')
+
+        x = sub([1, 1])
+        assert_equal(repr(x), 'sub([1, 1])')
+        assert_equal(str(x), '[1 1]')
+
+        # check it works properly with object arrays too
+        x = sub(None)
+        assert_equal(repr(x), 'sub(None, dtype=object)')
+        assert_equal(str(x), 'None')
+
+        # plus recursive object arrays (even depth > 1)
+        y = sub(None)
+        x[()] = y
+        y[()] = x
+        assert_equal(repr(x),
+            'sub(sub(sub(..., dtype=object), dtype=object), dtype=object)')
+        assert_equal(str(x), '...')
+        x[()] = 0  # resolve circular references for garbage collector
+
+        # nested 0d-subclass-object
+        x = sub(None)
+        x[()] = sub(None)
+        assert_equal(repr(x), 'sub(sub(None, dtype=object), dtype=object)')
+        assert_equal(str(x), 'None')
+
+        # gh-10663
+        class DuckCounter(np.ndarray):
+            def __getitem__(self, item):
+                result = super().__getitem__(item)
+                if not isinstance(result, DuckCounter):
+                    result = result[...].view(DuckCounter)
+                return result
+
+            def to_string(self):
+                return {0: 'zero', 1: 'one', 2: 'two'}.get(self.item(), 'many')
+
+            def __str__(self):
+                if self.shape == ():
+                    return self.to_string()
+                else:
+                    fmt = {'all': lambda x: x.to_string()}
+                    return np.array2string(self, formatter=fmt)
+
+        dc = np.arange(5).view(DuckCounter)
+        assert_equal(str(dc), "[zero one two many many]")
+        assert_equal(str(dc[0]), "zero")
+
+    def test_self_containing(self):
+        arr0d = np.array(None)
+        arr0d[()] = arr0d
+        assert_equal(repr(arr0d),
+            'array(array(..., dtype=object), dtype=object)')
+        arr0d[()] = 0  # resolve recursion for garbage collector
+
+        arr1d = np.array([None, None])
+        arr1d[1] = arr1d
+        assert_equal(repr(arr1d),
+            'array([None, array(..., dtype=object)], dtype=object)')
+        arr1d[1] = 0  # resolve recursion for garbage collector
+
+        first = np.array(None)
+        second = np.array(None)
+        first[()] = second
+        second[()] = first
+        assert_equal(repr(first),
+            'array(array(array(..., dtype=object), dtype=object), dtype=object)')
+        first[()] = 0  # resolve circular references for garbage collector
+
+    def test_containing_list(self):
+        # printing square brackets directly would be ambiguuous
+        arr1d = np.array([None, None])
+        arr1d[0] = [1, 2]
+        arr1d[1] = [3]
+        assert_equal(repr(arr1d),
+            'array([list([1, 2]), list([3])], dtype=object)')
+
+    def test_void_scalar_recursion(self):
+        # gh-9345
+        repr(np.void(b'test'))  # RecursionError ?
+
+    def test_fieldless_structured(self):
+        # gh-10366
+        no_fields = np.dtype([])
+        arr_no_fields = np.empty(4, dtype=no_fields)
+        assert_equal(repr(arr_no_fields), 'array([(), (), (), ()], dtype=[])')
+
+
+class TestComplexArray:
+    def test_str(self):
+        rvals = [0, 1, -1, np.inf, -np.inf, np.nan]
+        cvals = [complex(rp, ip) for rp in rvals for ip in rvals]
+        dtypes = [np.complex64, np.cdouble, np.clongdouble]
+        actual = [str(np.array([c], dt)) for c in cvals for dt in dtypes]
+        wanted = [
+            '[0.+0.j]',    '[0.+0.j]',    '[0.+0.j]',
+            '[0.+1.j]',    '[0.+1.j]',    '[0.+1.j]',
+            '[0.-1.j]',    '[0.-1.j]',    '[0.-1.j]',
+            '[0.+infj]',   '[0.+infj]',   '[0.+infj]',
+            '[0.-infj]',   '[0.-infj]',   '[0.-infj]',
+            '[0.+nanj]',   '[0.+nanj]',   '[0.+nanj]',
+            '[1.+0.j]',    '[1.+0.j]',    '[1.+0.j]',
+            '[1.+1.j]',    '[1.+1.j]',    '[1.+1.j]',
+            '[1.-1.j]',    '[1.-1.j]',    '[1.-1.j]',
+            '[1.+infj]',   '[1.+infj]',   '[1.+infj]',
+            '[1.-infj]',   '[1.-infj]',   '[1.-infj]',
+            '[1.+nanj]',   '[1.+nanj]',   '[1.+nanj]',
+            '[-1.+0.j]',   '[-1.+0.j]',   '[-1.+0.j]',
+            '[-1.+1.j]',   '[-1.+1.j]',   '[-1.+1.j]',
+            '[-1.-1.j]',   '[-1.-1.j]',   '[-1.-1.j]',
+            '[-1.+infj]',  '[-1.+infj]',  '[-1.+infj]',
+            '[-1.-infj]',  '[-1.-infj]',  '[-1.-infj]',
+            '[-1.+nanj]',  '[-1.+nanj]',  '[-1.+nanj]',
+            '[inf+0.j]',   '[inf+0.j]',   '[inf+0.j]',
+            '[inf+1.j]',   '[inf+1.j]',   '[inf+1.j]',
+            '[inf-1.j]',   '[inf-1.j]',   '[inf-1.j]',
+            '[inf+infj]',  '[inf+infj]',  '[inf+infj]',
+            '[inf-infj]',  '[inf-infj]',  '[inf-infj]',
+            '[inf+nanj]',  '[inf+nanj]',  '[inf+nanj]',
+            '[-inf+0.j]',  '[-inf+0.j]',  '[-inf+0.j]',
+            '[-inf+1.j]',  '[-inf+1.j]',  '[-inf+1.j]',
+            '[-inf-1.j]',  '[-inf-1.j]',  '[-inf-1.j]',
+            '[-inf+infj]', '[-inf+infj]', '[-inf+infj]',
+            '[-inf-infj]', '[-inf-infj]', '[-inf-infj]',
+            '[-inf+nanj]', '[-inf+nanj]', '[-inf+nanj]',
+            '[nan+0.j]',   '[nan+0.j]',   '[nan+0.j]',
+            '[nan+1.j]',   '[nan+1.j]',   '[nan+1.j]',
+            '[nan-1.j]',   '[nan-1.j]',   '[nan-1.j]',
+            '[nan+infj]',  '[nan+infj]',  '[nan+infj]',
+            '[nan-infj]',  '[nan-infj]',  '[nan-infj]',
+            '[nan+nanj]',  '[nan+nanj]',  '[nan+nanj]']
+
+        for res, val in zip(actual, wanted):
+            assert_equal(res, val)
+
+class TestArray2String:
+    def test_basic(self):
+        """Basic test of array2string."""
+        a = np.arange(3)
+        assert_(np.array2string(a) == '[0 1 2]')
+        assert_(np.array2string(a, max_line_width=4, legacy='1.13') == '[0 1\n 2]')
+        assert_(np.array2string(a, max_line_width=4) == '[0\n 1\n 2]')
+
+    def test_unexpected_kwarg(self):
+        # ensure than an appropriate TypeError
+        # is raised when array2string receives
+        # an unexpected kwarg
+
+        with assert_raises_regex(TypeError, 'nonsense'):
+            np.array2string(np.array([1, 2, 3]),
+                            nonsense=None)
+
+    def test_format_function(self):
+        """Test custom format function for each element in array."""
+        def _format_function(x):
+            if np.abs(x) < 1:
+                return '.'
+            elif np.abs(x) < 2:
+                return 'o'
+            else:
+                return 'O'
+
+        x = np.arange(3)
+        x_hex = "[0x0 0x1 0x2]"
+        x_oct = "[0o0 0o1 0o2]"
+        assert_(np.array2string(x, formatter={'all':_format_function}) ==
+                "[. o O]")
+        assert_(np.array2string(x, formatter={'int_kind':_format_function}) ==
+                "[. o O]")
+        assert_(np.array2string(x, formatter={'all':lambda x: "%.4f" % x}) ==
+                "[0.0000 1.0000 2.0000]")
+        assert_equal(np.array2string(x, formatter={'int':lambda x: hex(x)}),
+                x_hex)
+        assert_equal(np.array2string(x, formatter={'int':lambda x: oct(x)}),
+                x_oct)
+
+        x = np.arange(3.)
+        assert_(np.array2string(x, formatter={'float_kind':lambda x: "%.2f" % x}) ==
+                "[0.00 1.00 2.00]")
+        assert_(np.array2string(x, formatter={'float':lambda x: "%.2f" % x}) ==
+                "[0.00 1.00 2.00]")
+
+        s = np.array(['abc', 'def'])
+        assert_(np.array2string(s, formatter={'numpystr':lambda s: s*2}) ==
+                '[abcabc defdef]')
+
+    def test_structure_format_mixed(self):
+        dt = np.dtype([('name', np.str_, 16), ('grades', np.float64, (2,))])
+        x = np.array([('Sarah', (8.0, 7.0)), ('John', (6.0, 7.0))], dtype=dt)
+        assert_equal(np.array2string(x),
+                "[('Sarah', [8., 7.]) ('John', [6., 7.])]")
+
+        np.set_printoptions(legacy='1.13')
+        try:
+            # for issue #5692
+            A = np.zeros(shape=10, dtype=[("A", "M8[s]")])
+            A[5:].fill(np.datetime64('NaT'))
+            assert_equal(
+                np.array2string(A),
+                textwrap.dedent("""\
+                [('1970-01-01T00:00:00',) ('1970-01-01T00:00:00',) ('1970-01-01T00:00:00',)
+                 ('1970-01-01T00:00:00',) ('1970-01-01T00:00:00',) ('NaT',) ('NaT',)
+                 ('NaT',) ('NaT',) ('NaT',)]""")
+            )
+        finally:
+            np.set_printoptions(legacy=False)
+
+        # same again, but with non-legacy behavior
+        assert_equal(
+            np.array2string(A),
+            textwrap.dedent("""\
+            [('1970-01-01T00:00:00',) ('1970-01-01T00:00:00',)
+             ('1970-01-01T00:00:00',) ('1970-01-01T00:00:00',)
+             ('1970-01-01T00:00:00',) (                'NaT',)
+             (                'NaT',) (                'NaT',)
+             (                'NaT',) (                'NaT',)]""")
+        )
+
+        # and again, with timedeltas
+        A = np.full(10, 123456, dtype=[("A", "m8[s]")])
+        A[5:].fill(np.datetime64('NaT'))
+        assert_equal(
+            np.array2string(A),
+            textwrap.dedent("""\
+            [(123456,) (123456,) (123456,) (123456,) (123456,) ( 'NaT',) ( 'NaT',)
+             ( 'NaT',) ( 'NaT',) ( 'NaT',)]""")
+        )
+
+    def test_structure_format_int(self):
+        # See #8160
+        struct_int = np.array([([1, -1],), ([123, 1],)], dtype=[('B', 'i4', 2)])
+        assert_equal(np.array2string(struct_int),
+                "[([  1,  -1],) ([123,   1],)]")
+        struct_2dint = np.array([([[0, 1], [2, 3]],), ([[12, 0], [0, 0]],)],
+                dtype=[('B', 'i4', (2, 2))])
+        assert_equal(np.array2string(struct_2dint),
+                "[([[ 0,  1], [ 2,  3]],) ([[12,  0], [ 0,  0]],)]")
+
+    def test_structure_format_float(self):
+        # See #8172
+        array_scalar = np.array(
+                (1., 2.1234567890123456789, 3.), dtype=('f8,f8,f8'))
+        assert_equal(np.array2string(array_scalar), "(1., 2.12345679, 3.)")
+
+    def test_unstructured_void_repr(self):
+        a = np.array([27, 91, 50, 75,  7, 65, 10,  8,
+                      27, 91, 51, 49,109, 82,101,100], dtype='u1').view('V8')
+        assert_equal(repr(a[0]), r"void(b'\x1B\x5B\x32\x4B\x07\x41\x0A\x08')")
+        assert_equal(str(a[0]), r"b'\x1B\x5B\x32\x4B\x07\x41\x0A\x08'")
+        assert_equal(repr(a),
+            r"array([b'\x1B\x5B\x32\x4B\x07\x41\x0A\x08'," "\n"
+            r"       b'\x1B\x5B\x33\x31\x6D\x52\x65\x64'], dtype='|V8')")
+
+        assert_equal(eval(repr(a), vars(np)), a)
+        assert_equal(eval(repr(a[0]), vars(np)), a[0])
+
+    def test_edgeitems_kwarg(self):
+        # previously the global print options would be taken over the kwarg
+        arr = np.zeros(3, int)
+        assert_equal(
+            np.array2string(arr, edgeitems=1, threshold=0),
+            "[0 ... 0]"
+        )
+
+    def test_summarize_1d(self):
+        A = np.arange(1001)
+        strA = '[   0    1    2 ...  998  999 1000]'
+        assert_equal(str(A), strA)
+
+        reprA = 'array([   0,    1,    2, ...,  998,  999, 1000])'
+        assert_equal(repr(A), reprA)
+
+    def test_summarize_2d(self):
+        A = np.arange(1002).reshape(2, 501)
+        strA = '[[   0    1    2 ...  498  499  500]\n' \
+               ' [ 501  502  503 ...  999 1000 1001]]'
+        assert_equal(str(A), strA)
+
+        reprA = 'array([[   0,    1,    2, ...,  498,  499,  500],\n' \
+                '       [ 501,  502,  503, ...,  999, 1000, 1001]])'
+        assert_equal(repr(A), reprA)
+
+    def test_summarize_structure(self):
+        A = (np.arange(2002, dtype="<i8").reshape(2, 1001)
+             .view([('i', "<i8", (1001,))]))
+        strA = ("[[([   0,    1,    2, ...,  998,  999, 1000],)]\n"
+                " [([1001, 1002, 1003, ..., 1999, 2000, 2001],)]]")
+        assert_equal(str(A), strA)
+
+        reprA = ("array([[([   0,    1,    2, ...,  998,  999, 1000],)],\n"
+                 "       [([1001, 1002, 1003, ..., 1999, 2000, 2001],)]],\n"
+                 "      dtype=[('i', '<i8', (1001,))])")
+        assert_equal(repr(A), reprA)
+
+        B = np.ones(2002, dtype=">i8").view([('i', ">i8", (2, 1001))])
+        strB = "[([[1, 1, 1, ..., 1, 1, 1], [1, 1, 1, ..., 1, 1, 1]],)]"
+        assert_equal(str(B), strB)
+
+        reprB = (
+            "array([([[1, 1, 1, ..., 1, 1, 1], [1, 1, 1, ..., 1, 1, 1]],)],\n"
+            "      dtype=[('i', '>i8', (2, 1001))])"
+        )
+        assert_equal(repr(B), reprB)
+
+        C = (np.arange(22, dtype="<i8").reshape(2, 11)
+             .view([('i1', "<i8"), ('i10', "<i8", (10,))]))
+        strC = "[[( 0, [ 1, ..., 10])]\n [(11, [12, ..., 21])]]"
+        assert_equal(np.array2string(C, threshold=1, edgeitems=1), strC)
+
+    def test_linewidth(self):
+        a = np.full(6, 1)
+
+        def make_str(a, width, **kw):
+            return np.array2string(a, separator="", max_line_width=width, **kw)
+
+        assert_equal(make_str(a, 8, legacy='1.13'), '[111111]')
+        assert_equal(make_str(a, 7, legacy='1.13'), '[111111]')
+        assert_equal(make_str(a, 5, legacy='1.13'), '[1111\n'
+                                                    ' 11]')
+
+        assert_equal(make_str(a, 8), '[111111]')
+        assert_equal(make_str(a, 7), '[11111\n'
+                                     ' 1]')
+        assert_equal(make_str(a, 5), '[111\n'
+                                     ' 111]')
+
+        b = a[None,None,:]
+
+        assert_equal(make_str(b, 12, legacy='1.13'), '[[[111111]]]')
+        assert_equal(make_str(b,  9, legacy='1.13'), '[[[111111]]]')
+        assert_equal(make_str(b,  8, legacy='1.13'), '[[[11111\n'
+                                                     '   1]]]')
+
+        assert_equal(make_str(b, 12), '[[[111111]]]')
+        assert_equal(make_str(b,  9), '[[[111\n'
+                                      '   111]]]')
+        assert_equal(make_str(b,  8), '[[[11\n'
+                                      '   11\n'
+                                      '   11]]]')
+
+    def test_wide_element(self):
+        a = np.array(['xxxxx'])
+        assert_equal(
+            np.array2string(a, max_line_width=5),
+            "['xxxxx']"
+        )
+        assert_equal(
+            np.array2string(a, max_line_width=5, legacy='1.13'),
+            "[ 'xxxxx']"
+        )
+
+    def test_multiline_repr(self):
+        class MultiLine:
+            def __repr__(self):
+                return "Line 1\nLine 2"
+
+        a = np.array([[None, MultiLine()], [MultiLine(), None]])
+
+        assert_equal(
+            np.array2string(a),
+            '[[None Line 1\n'
+            '       Line 2]\n'
+            ' [Line 1\n'
+            '  Line 2 None]]'
+        )
+        assert_equal(
+            np.array2string(a, max_line_width=5),
+            '[[None\n'
+            '  Line 1\n'
+            '  Line 2]\n'
+            ' [Line 1\n'
+            '  Line 2\n'
+            '  None]]'
+        )
+        assert_equal(
+            repr(a),
+            'array([[None, Line 1\n'
+            '              Line 2],\n'
+            '       [Line 1\n'
+            '        Line 2, None]], dtype=object)'
+        )
+
+        class MultiLineLong:
+            def __repr__(self):
+                return "Line 1\nLooooooooooongestLine2\nLongerLine 3"
+
+        a = np.array([[None, MultiLineLong()], [MultiLineLong(), None]])
+        assert_equal(
+            repr(a),
+            'array([[None, Line 1\n'
+            '              LooooooooooongestLine2\n'
+            '              LongerLine 3          ],\n'
+            '       [Line 1\n'
+            '        LooooooooooongestLine2\n'
+            '        LongerLine 3          , None]], dtype=object)'
+        )
+        assert_equal(
+            np.array_repr(a, 20),
+            'array([[None,\n'
+            '        Line 1\n'
+            '        LooooooooooongestLine2\n'
+            '        LongerLine 3          ],\n'
+            '       [Line 1\n'
+            '        LooooooooooongestLine2\n'
+            '        LongerLine 3          ,\n'
+            '        None]],\n'
+            '      dtype=object)'
+        )
+
+    def test_nested_array_repr(self):
+        a = np.empty((2, 2), dtype=object)
+        a[0, 0] = np.eye(2)
+        a[0, 1] = np.eye(3)
+        a[1, 0] = None
+        a[1, 1] = np.ones((3, 1))
+        assert_equal(
+            repr(a),
+            'array([[array([[1., 0.],\n'
+            '               [0., 1.]]), array([[1., 0., 0.],\n'
+            '                                  [0., 1., 0.],\n'
+            '                                  [0., 0., 1.]])],\n'
+            '       [None, array([[1.],\n'
+            '                     [1.],\n'
+            '                     [1.]])]], dtype=object)'
+        )
+
+    @given(hynp.from_dtype(np.dtype("U")))
+    def test_any_text(self, text):
+        # This test checks that, given any value that can be represented in an
+        # array of dtype("U") (i.e. unicode string), ...
+        a = np.array([text, text, text])
+        # casting a list of them to an array does not e.g. truncate the value
+        assert_equal(a[0], text)
+        # and that np.array2string puts a newline in the expected location
+        expected_repr = "[{0!r} {0!r}\n {0!r}]".format(text)
+        result = np.array2string(a, max_line_width=len(repr(text)) * 2 + 3)
+        assert_equal(result, expected_repr)
+
+    @pytest.mark.skipif(not HAS_REFCOUNT, reason="Python lacks refcounts")
+    def test_refcount(self):
+        # make sure we do not hold references to the array due to a recursive
+        # closure (gh-10620)
+        gc.disable()
+        a = np.arange(2)
+        r1 = sys.getrefcount(a)
+        np.array2string(a)
+        np.array2string(a)
+        r2 = sys.getrefcount(a)
+        gc.collect()
+        gc.enable()
+        assert_(r1 == r2)
+
+class TestPrintOptions:
+    """Test getting and setting global print options."""
+
+    def setup_method(self):
+        self.oldopts = np.get_printoptions()
+
+    def teardown_method(self):
+        np.set_printoptions(**self.oldopts)
+
+    def test_basic(self):
+        x = np.array([1.5, 0, 1.234567890])
+        assert_equal(repr(x), "array([1.5       , 0.        , 1.23456789])")
+        np.set_printoptions(precision=4)
+        assert_equal(repr(x), "array([1.5   , 0.    , 1.2346])")
+
+    def test_precision_zero(self):
+        np.set_printoptions(precision=0)
+        for values, string in (
+                ([0.], "0."), ([.3], "0."), ([-.3], "-0."), ([.7], "1."),
+                ([1.5], "2."), ([-1.5], "-2."), ([-15.34], "-15."),
+                ([100.], "100."), ([.2, -1, 122.51], "  0.,  -1., 123."),
+                ([0], "0"), ([-12], "-12"), ([complex(.3, -.7)], "0.-1.j")):
+            x = np.array(values)
+            assert_equal(repr(x), "array([%s])" % string)
+
+    def test_formatter(self):
+        x = np.arange(3)
+        np.set_printoptions(formatter={'all':lambda x: str(x-1)})
+        assert_equal(repr(x), "array([-1, 0, 1])")
+
+    def test_formatter_reset(self):
+        x = np.arange(3)
+        np.set_printoptions(formatter={'all':lambda x: str(x-1)})
+        assert_equal(repr(x), "array([-1, 0, 1])")
+        np.set_printoptions(formatter={'int':None})
+        assert_equal(repr(x), "array([0, 1, 2])")
+
+        np.set_printoptions(formatter={'all':lambda x: str(x-1)})
+        assert_equal(repr(x), "array([-1, 0, 1])")
+        np.set_printoptions(formatter={'all':None})
+        assert_equal(repr(x), "array([0, 1, 2])")
+
+        np.set_printoptions(formatter={'int':lambda x: str(x-1)})
+        assert_equal(repr(x), "array([-1, 0, 1])")
+        np.set_printoptions(formatter={'int_kind':None})
+        assert_equal(repr(x), "array([0, 1, 2])")
+
+        x = np.arange(3.)
+        np.set_printoptions(formatter={'float':lambda x: str(x-1)})
+        assert_equal(repr(x), "array([-1.0, 0.0, 1.0])")
+        np.set_printoptions(formatter={'float_kind':None})
+        assert_equal(repr(x), "array([0., 1., 2.])")
+
+    def test_0d_arrays(self):
+        assert_equal(str(np.array('café', '<U4')), 'café')
+
+        assert_equal(repr(np.array('café', '<U4')),
+                     "array('café', dtype='<U4')")
+        assert_equal(str(np.array('test', np.str_)), 'test')
+
+        a = np.zeros(1, dtype=[('a', '<i4', (3,))])
+        assert_equal(str(a[0]), '([0, 0, 0],)')
+
+        assert_equal(repr(np.datetime64('2005-02-25')[...]),
+                     "array('2005-02-25', dtype='datetime64[D]')")
+
+        assert_equal(repr(np.timedelta64('10', 'Y')[...]),
+                     "array(10, dtype='timedelta64[Y]')")
+
+        # repr of 0d arrays is affected by printoptions
+        x = np.array(1)
+        np.set_printoptions(formatter={'all':lambda x: "test"})
+        assert_equal(repr(x), "array(test)")
+        # str is unaffected
+        assert_equal(str(x), "1")
+
+        # check `style` arg raises
+        assert_warns(DeprecationWarning, np.array2string,
+                                         np.array(1.), style=repr)
+        # but not in legacy mode
+        np.array2string(np.array(1.), style=repr, legacy='1.13')
+        # gh-10934 style was broken in legacy mode, check it works
+        np.array2string(np.array(1.), legacy='1.13')
+
+    def test_float_spacing(self):
+        x = np.array([1., 2., 3.])
+        y = np.array([1., 2., -10.])
+        z = np.array([100., 2., -1.])
+        w = np.array([-100., 2., 1.])
+
+        assert_equal(repr(x), 'array([1., 2., 3.])')
+        assert_equal(repr(y), 'array([  1.,   2., -10.])')
+        assert_equal(repr(np.array(y[0])), 'array(1.)')
+        assert_equal(repr(np.array(y[-1])), 'array(-10.)')
+        assert_equal(repr(z), 'array([100.,   2.,  -1.])')
+        assert_equal(repr(w), 'array([-100.,    2.,    1.])')
+
+        assert_equal(repr(np.array([np.nan, np.inf])), 'array([nan, inf])')
+        assert_equal(repr(np.array([np.nan, -np.inf])), 'array([ nan, -inf])')
+
+        x = np.array([np.inf, 100000, 1.1234])
+        y = np.array([np.inf, 100000, -1.1234])
+        z = np.array([np.inf, 1.1234, -1e120])
+        np.set_printoptions(precision=2)
+        assert_equal(repr(x), 'array([     inf, 1.00e+05, 1.12e+00])')
+        assert_equal(repr(y), 'array([      inf,  1.00e+05, -1.12e+00])')
+        assert_equal(repr(z), 'array([       inf,  1.12e+000, -1.00e+120])')
+
+    def test_bool_spacing(self):
+        assert_equal(repr(np.array([True,  True])),
+                     'array([ True,  True])')
+        assert_equal(repr(np.array([True, False])),
+                     'array([ True, False])')
+        assert_equal(repr(np.array([True])),
+                     'array([ True])')
+        assert_equal(repr(np.array(True)),
+                     'array(True)')
+        assert_equal(repr(np.array(False)),
+                     'array(False)')
+
+    def test_sign_spacing(self):
+        a = np.arange(4.)
+        b = np.array([1.234e9])
+        c = np.array([1.0 + 1.0j, 1.123456789 + 1.123456789j], dtype='c16')
+
+        assert_equal(repr(a), 'array([0., 1., 2., 3.])')
+        assert_equal(repr(np.array(1.)), 'array(1.)')
+        assert_equal(repr(b), 'array([1.234e+09])')
+        assert_equal(repr(np.array([0.])), 'array([0.])')
+        assert_equal(repr(c),
+            "array([1.        +1.j        , 1.12345679+1.12345679j])")
+        assert_equal(repr(np.array([0., -0.])), 'array([ 0., -0.])')
+
+        np.set_printoptions(sign=' ')
+        assert_equal(repr(a), 'array([ 0.,  1.,  2.,  3.])')
+        assert_equal(repr(np.array(1.)), 'array( 1.)')
+        assert_equal(repr(b), 'array([ 1.234e+09])')
+        assert_equal(repr(c),
+            "array([ 1.        +1.j        ,  1.12345679+1.12345679j])")
+        assert_equal(repr(np.array([0., -0.])), 'array([ 0., -0.])')
+
+        np.set_printoptions(sign='+')
+        assert_equal(repr(a), 'array([+0., +1., +2., +3.])')
+        assert_equal(repr(np.array(1.)), 'array(+1.)')
+        assert_equal(repr(b), 'array([+1.234e+09])')
+        assert_equal(repr(c),
+            "array([+1.        +1.j        , +1.12345679+1.12345679j])")
+
+        np.set_printoptions(legacy='1.13')
+        assert_equal(repr(a), 'array([ 0.,  1.,  2.,  3.])')
+        assert_equal(repr(b),  'array([  1.23400000e+09])')
+        assert_equal(repr(-b), 'array([ -1.23400000e+09])')
+        assert_equal(repr(np.array(1.)), 'array(1.0)')
+        assert_equal(repr(np.array([0.])), 'array([ 0.])')
+        assert_equal(repr(c),
+            "array([ 1.00000000+1.j        ,  1.12345679+1.12345679j])")
+        # gh-10383
+        assert_equal(str(np.array([-1., 10])), "[ -1.  10.]")
+
+        assert_raises(TypeError, np.set_printoptions, wrongarg=True)
+
+    def test_float_overflow_nowarn(self):
+        # make sure internal computations in FloatingFormat don't
+        # warn about overflow
+        repr(np.array([1e4, 0.1], dtype='f2'))
+
+    def test_sign_spacing_structured(self):
+        a = np.ones(2, dtype='<f,<f')
+        assert_equal(repr(a),
+            "array([(1., 1.), (1., 1.)], dtype=[('f0', '<f4'), ('f1', '<f4')])")
+        assert_equal(repr(a[0]), "(1., 1.)")
+
+    def test_floatmode(self):
+        x = np.array([0.6104, 0.922, 0.457, 0.0906, 0.3733, 0.007244,
+                      0.5933, 0.947, 0.2383, 0.4226], dtype=np.float16)
+        y = np.array([0.2918820979355541, 0.5064172631089138,
+                      0.2848750619642916, 0.4342965294660567,
+                      0.7326538397312751, 0.3459503329096204,
+                      0.0862072768214508, 0.39112753029631175],
+                      dtype=np.float64)
+        z = np.arange(6, dtype=np.float16)/10
+        c = np.array([1.0 + 1.0j, 1.123456789 + 1.123456789j], dtype='c16')
+
+        # also make sure 1e23 is right (is between two fp numbers)
+        w = np.array(['1e{}'.format(i) for i in range(25)], dtype=np.float64)
+        # note: we construct w from the strings `1eXX` instead of doing
+        # `10.**arange(24)` because it turns out the two are not equivalent in
+        # python. On some architectures `1e23 != 10.**23`.
+        wp = np.array([1.234e1, 1e2, 1e123])
+
+        # unique mode
+        np.set_printoptions(floatmode='unique')
+        assert_equal(repr(x),
+            "array([0.6104  , 0.922   , 0.457   , 0.0906  , 0.3733  , 0.007244,\n"
+            "       0.5933  , 0.947   , 0.2383  , 0.4226  ], dtype=float16)")
+        assert_equal(repr(y),
+            "array([0.2918820979355541 , 0.5064172631089138 , 0.2848750619642916 ,\n"
+            "       0.4342965294660567 , 0.7326538397312751 , 0.3459503329096204 ,\n"
+            "       0.0862072768214508 , 0.39112753029631175])")
+        assert_equal(repr(z),
+            "array([0. , 0.1, 0.2, 0.3, 0.4, 0.5], dtype=float16)")
+        assert_equal(repr(w),
+            "array([1.e+00, 1.e+01, 1.e+02, 1.e+03, 1.e+04, 1.e+05, 1.e+06, 1.e+07,\n"
+            "       1.e+08, 1.e+09, 1.e+10, 1.e+11, 1.e+12, 1.e+13, 1.e+14, 1.e+15,\n"
+            "       1.e+16, 1.e+17, 1.e+18, 1.e+19, 1.e+20, 1.e+21, 1.e+22, 1.e+23,\n"
+            "       1.e+24])")
+        assert_equal(repr(wp), "array([1.234e+001, 1.000e+002, 1.000e+123])")
+        assert_equal(repr(c),
+            "array([1.         +1.j         , 1.123456789+1.123456789j])")
+
+        # maxprec mode, precision=8
+        np.set_printoptions(floatmode='maxprec', precision=8)
+        assert_equal(repr(x),
+            "array([0.6104  , 0.922   , 0.457   , 0.0906  , 0.3733  , 0.007244,\n"
+            "       0.5933  , 0.947   , 0.2383  , 0.4226  ], dtype=float16)")
+        assert_equal(repr(y),
+            "array([0.2918821 , 0.50641726, 0.28487506, 0.43429653, 0.73265384,\n"
+            "       0.34595033, 0.08620728, 0.39112753])")
+        assert_equal(repr(z),
+            "array([0. , 0.1, 0.2, 0.3, 0.4, 0.5], dtype=float16)")
+        assert_equal(repr(w[::5]),
+            "array([1.e+00, 1.e+05, 1.e+10, 1.e+15, 1.e+20])")
+        assert_equal(repr(wp), "array([1.234e+001, 1.000e+002, 1.000e+123])")
+        assert_equal(repr(c),
+            "array([1.        +1.j        , 1.12345679+1.12345679j])")
+
+        # fixed mode, precision=4
+        np.set_printoptions(floatmode='fixed', precision=4)
+        assert_equal(repr(x),
+            "array([0.6104, 0.9219, 0.4570, 0.0906, 0.3733, 0.0072, 0.5933, 0.9468,\n"
+            "       0.2383, 0.4226], dtype=float16)")
+        assert_equal(repr(y),
+            "array([0.2919, 0.5064, 0.2849, 0.4343, 0.7327, 0.3460, 0.0862, 0.3911])")
+        assert_equal(repr(z),
+            "array([0.0000, 0.1000, 0.2000, 0.3000, 0.3999, 0.5000], dtype=float16)")
+        assert_equal(repr(w[::5]),
+            "array([1.0000e+00, 1.0000e+05, 1.0000e+10, 1.0000e+15, 1.0000e+20])")
+        assert_equal(repr(wp), "array([1.2340e+001, 1.0000e+002, 1.0000e+123])")
+        assert_equal(repr(np.zeros(3)), "array([0.0000, 0.0000, 0.0000])")
+        assert_equal(repr(c),
+            "array([1.0000+1.0000j, 1.1235+1.1235j])")
+        # for larger precision, representation error becomes more apparent:
+        np.set_printoptions(floatmode='fixed', precision=8)
+        assert_equal(repr(z),
+            "array([0.00000000, 0.09997559, 0.19995117, 0.30004883, 0.39990234,\n"
+            "       0.50000000], dtype=float16)")
+
+        # maxprec_equal  mode, precision=8
+        np.set_printoptions(floatmode='maxprec_equal', precision=8)
+        assert_equal(repr(x),
+            "array([0.610352, 0.921875, 0.457031, 0.090576, 0.373291, 0.007244,\n"
+            "       0.593262, 0.946777, 0.238281, 0.422607], dtype=float16)")
+        assert_equal(repr(y),
+            "array([0.29188210, 0.50641726, 0.28487506, 0.43429653, 0.73265384,\n"
+            "       0.34595033, 0.08620728, 0.39112753])")
+        assert_equal(repr(z),
+            "array([0.0, 0.1, 0.2, 0.3, 0.4, 0.5], dtype=float16)")
+        assert_equal(repr(w[::5]),
+            "array([1.e+00, 1.e+05, 1.e+10, 1.e+15, 1.e+20])")
+        assert_equal(repr(wp), "array([1.234e+001, 1.000e+002, 1.000e+123])")
+        assert_equal(repr(c),
+            "array([1.00000000+1.00000000j, 1.12345679+1.12345679j])")
+
+        # test unique special case (gh-18609)
+        a = np.float64.fromhex('-1p-97')
+        assert_equal(np.float64(np.array2string(a, floatmode='unique')), a)
+
+    def test_legacy_mode_scalars(self):
+        # in legacy mode, str of floats get truncated, and complex scalars
+        # use * for non-finite imaginary part
+        np.set_printoptions(legacy='1.13')
+        assert_equal(str(np.float64(1.123456789123456789)), '1.12345678912')
+        assert_equal(str(np.complex128(complex(1, np.nan))), '(1+nan*j)')
+
+        np.set_printoptions(legacy=False)
+        assert_equal(str(np.float64(1.123456789123456789)),
+                     '1.1234567891234568')
+        assert_equal(str(np.complex128(complex(1, np.nan))), '(1+nanj)')
+
+    def test_legacy_stray_comma(self):
+        np.set_printoptions(legacy='1.13')
+        assert_equal(str(np.arange(10000)), '[   0    1    2 ..., 9997 9998 9999]')
+
+        np.set_printoptions(legacy=False)
+        assert_equal(str(np.arange(10000)), '[   0    1    2 ... 9997 9998 9999]')
+
+    def test_dtype_linewidth_wrapping(self):
+        np.set_printoptions(linewidth=75)
+        assert_equal(repr(np.arange(10,20., dtype='f4')),
+            "array([10., 11., 12., 13., 14., 15., 16., 17., 18., 19.], dtype=float32)")
+        assert_equal(repr(np.arange(10,23., dtype='f4')), textwrap.dedent("""\
+            array([10., 11., 12., 13., 14., 15., 16., 17., 18., 19., 20., 21., 22.],
+                  dtype=float32)"""))
+
+        styp = '<U4'
+        assert_equal(repr(np.ones(3, dtype=styp)),
+            "array(['1', '1', '1'], dtype='{}')".format(styp))
+        assert_equal(repr(np.ones(12, dtype=styp)), textwrap.dedent("""\
+            array(['1', '1', '1', '1', '1', '1', '1', '1', '1', '1', '1', '1'],
+                  dtype='{}')""".format(styp)))
+
+    @pytest.mark.parametrize(
+        ['native'],
+        [
+            ('bool',),
+            ('uint8',),
+            ('uint16',),
+            ('uint32',),
+            ('uint64',),
+            ('int8',),
+            ('int16',),
+            ('int32',),
+            ('int64',),
+            ('float16',),
+            ('float32',),
+            ('float64',),
+            ('U1',),     # 4-byte width string
+        ],
+    )
+    def test_dtype_endianness_repr(self, native):
+        '''
+        there was an issue where
+        repr(array([0], dtype='<u2')) and repr(array([0], dtype='>u2'))
+        both returned the same thing:
+        array([0], dtype=uint16)
+        even though their dtypes have different endianness.
+        '''
+        native_dtype = np.dtype(native)
+        non_native_dtype = native_dtype.newbyteorder()
+        non_native_repr = repr(np.array([1], non_native_dtype))
+        native_repr = repr(np.array([1], native_dtype))
+        # preserve the sensible default of only showing dtype if nonstandard
+        assert ('dtype' in native_repr) ^ (native_dtype in _typelessdata),\
+                ("an array's repr should show dtype if and only if the type "
+                 'of the array is NOT one of the standard types '
+                 '(e.g., int32, bool, float64).')
+        if non_native_dtype.itemsize > 1:
+            # if the type is >1 byte, the non-native endian version
+            # must show endianness.
+            assert non_native_repr != native_repr
+            assert f"dtype='{non_native_dtype.byteorder}" in non_native_repr
+
+    def test_linewidth_repr(self):
+        a = np.full(7, fill_value=2)
+        np.set_printoptions(linewidth=17)
+        assert_equal(
+            repr(a),
+            textwrap.dedent("""\
+            array([2, 2, 2,
+                   2, 2, 2,
+                   2])""")
+        )
+        np.set_printoptions(linewidth=17, legacy='1.13')
+        assert_equal(
+            repr(a),
+            textwrap.dedent("""\
+            array([2, 2, 2,
+                   2, 2, 2, 2])""")
+        )
+
+        a = np.full(8, fill_value=2)
+
+        np.set_printoptions(linewidth=18, legacy=False)
+        assert_equal(
+            repr(a),
+            textwrap.dedent("""\
+            array([2, 2, 2,
+                   2, 2, 2,
+                   2, 2])""")
+        )
+
+        np.set_printoptions(linewidth=18, legacy='1.13')
+        assert_equal(
+            repr(a),
+            textwrap.dedent("""\
+            array([2, 2, 2, 2,
+                   2, 2, 2, 2])""")
+        )
+
+    def test_linewidth_str(self):
+        a = np.full(18, fill_value=2)
+        np.set_printoptions(linewidth=18)
+        assert_equal(
+            str(a),
+            textwrap.dedent("""\
+            [2 2 2 2 2 2 2 2
+             2 2 2 2 2 2 2 2
+             2 2]""")
+        )
+        np.set_printoptions(linewidth=18, legacy='1.13')
+        assert_equal(
+            str(a),
+            textwrap.dedent("""\
+            [2 2 2 2 2 2 2 2 2
+             2 2 2 2 2 2 2 2 2]""")
+        )
+
+    def test_edgeitems(self):
+        np.set_printoptions(edgeitems=1, threshold=1)
+        a = np.arange(27).reshape((3, 3, 3))
+        assert_equal(
+            repr(a),
+            textwrap.dedent("""\
+            array([[[ 0, ...,  2],
+                    ...,
+                    [ 6, ...,  8]],
+
+                   ...,
+
+                   [[18, ..., 20],
+                    ...,
+                    [24, ..., 26]]])""")
+        )
+
+        b = np.zeros((3, 3, 1, 1))
+        assert_equal(
+            repr(b),
+            textwrap.dedent("""\
+            array([[[[0.]],
+
+                    ...,
+
+                    [[0.]]],
+
+
+                   ...,
+
+
+                   [[[0.]],
+
+                    ...,
+
+                    [[0.]]]])""")
+        )
+
+        # 1.13 had extra trailing spaces, and was missing newlines
+        np.set_printoptions(legacy='1.13')
+
+        assert_equal(
+            repr(a),
+            textwrap.dedent("""\
+            array([[[ 0, ...,  2],
+                    ..., 
+                    [ 6, ...,  8]],
+
+                   ..., 
+                   [[18, ..., 20],
+                    ..., 
+                    [24, ..., 26]]])""")
+        )
+
+        assert_equal(
+            repr(b),
+            textwrap.dedent("""\
+            array([[[[ 0.]],
+
+                    ..., 
+                    [[ 0.]]],
+
+
+                   ..., 
+                   [[[ 0.]],
+
+                    ..., 
+                    [[ 0.]]]])""")
+        )
+
+    def test_edgeitems_structured(self):
+        np.set_printoptions(edgeitems=1, threshold=1)
+        A = np.arange(5*2*3, dtype="<i8").view([('i', "<i8", (5, 2, 3))])
+        reprA = (
+            "array([([[[ 0, ...,  2], [ 3, ...,  5]], ..., "
+            "[[24, ..., 26], [27, ..., 29]]],)],\n"
+            "      dtype=[('i', '<i8', (5, 2, 3))])"
+        )
+        assert_equal(repr(A), reprA)
+
+    def test_bad_args(self):
+        assert_raises(ValueError, np.set_printoptions, threshold=float('nan'))
+        assert_raises(TypeError, np.set_printoptions, threshold='1')
+        assert_raises(TypeError, np.set_printoptions, threshold=b'1')
+
+        assert_raises(TypeError, np.set_printoptions, precision='1')
+        assert_raises(TypeError, np.set_printoptions, precision=1.5)
+
+def test_unicode_object_array():
+    expected = "array(['é'], dtype=object)"
+    x = np.array(['\xe9'], dtype=object)
+    assert_equal(repr(x), expected)
+
+
+class TestContextManager:
+    def test_ctx_mgr(self):
+        # test that context manager actually works
+        with np.printoptions(precision=2):
+            s = str(np.array([2.0]) / 3)
+        assert_equal(s, '[0.67]')
+
+    def test_ctx_mgr_restores(self):
+        # test that print options are actually restrored
+        opts = np.get_printoptions()
+        with np.printoptions(precision=opts['precision'] - 1,
+                             linewidth=opts['linewidth'] - 4):
+            pass
+        assert_equal(np.get_printoptions(), opts)
+
+    def test_ctx_mgr_exceptions(self):
+        # test that print options are restored even if an exception is raised
+        opts = np.get_printoptions()
+        try:
+            with np.printoptions(precision=2, linewidth=11):
+                raise ValueError
+        except ValueError:
+            pass
+        assert_equal(np.get_printoptions(), opts)
+
+    def test_ctx_mgr_as_smth(self):
+        opts = {"precision": 2}
+        with np.printoptions(**opts) as ctx:
+            saved_opts = ctx.copy()
+        assert_equal({k: saved_opts[k] for k in opts}, opts)

.venv/lib/python3.11/site-packages/numpy/core/tests/test_casting_floatingpoint_errors.py

@@ -0,0 +1,154 @@
+import pytest
+from pytest import param
+from numpy.testing import IS_WASM
+import numpy as np
+
+
+def values_and_dtypes():
+    """
+    Generate value+dtype pairs that generate floating point errors during
+    casts.  The invalid casts to integers will generate "invalid" value
+    warnings, the float casts all generate "overflow".
+
+    (The Python int/float paths don't need to get tested in all the same
+    situations, but it does not hurt.)
+    """
+    # Casting to float16:
+    yield param(70000, "float16", id="int-to-f2")
+    yield param("70000", "float16", id="str-to-f2")
+    yield param(70000.0, "float16", id="float-to-f2")
+    yield param(np.longdouble(70000.), "float16", id="longdouble-to-f2")
+    yield param(np.float64(70000.), "float16", id="double-to-f2")
+    yield param(np.float32(70000.), "float16", id="float-to-f2")
+    # Casting to float32:
+    yield param(10**100, "float32", id="int-to-f4")
+    yield param(1e100, "float32", id="float-to-f2")
+    yield param(np.longdouble(1e300), "float32", id="longdouble-to-f2")
+    yield param(np.float64(1e300), "float32", id="double-to-f2")
+    # Casting to float64:
+    # If longdouble is double-double, its max can be rounded down to the double
+    # max.  So we correct the double spacing (a bit weird, admittedly):
+    max_ld = np.finfo(np.longdouble).max
+    spacing = np.spacing(np.nextafter(np.finfo("f8").max, 0))
+    if max_ld - spacing > np.finfo("f8").max:
+        yield param(np.finfo(np.longdouble).max, "float64",
+                    id="longdouble-to-f8")
+
+    # Cast to complex32:
+    yield param(2e300, "complex64", id="float-to-c8")
+    yield param(2e300+0j, "complex64", id="complex-to-c8")
+    yield param(2e300j, "complex64", id="complex-to-c8")
+    yield param(np.longdouble(2e300), "complex64", id="longdouble-to-c8")
+
+    # Invalid float to integer casts:
+    with np.errstate(over="ignore"):
+        for to_dt in np.typecodes["AllInteger"]:
+            for value in [np.inf, np.nan]:
+                for from_dt in np.typecodes["AllFloat"]:
+                    from_dt = np.dtype(from_dt)
+                    from_val = from_dt.type(value)
+
+                    yield param(from_val, to_dt, id=f"{from_val}-to-{to_dt}")
+
+
+def check_operations(dtype, value):
+    """
+    There are many dedicated paths in NumPy which cast and should check for
+    floating point errors which occurred during those casts.
+    """
+    if dtype.kind != 'i':
+        # These assignments use the stricter setitem logic:
+        def assignment():
+            arr = np.empty(3, dtype=dtype)
+            arr[0] = value
+
+        yield assignment
+
+        def fill():
+            arr = np.empty(3, dtype=dtype)
+            arr.fill(value)
+
+        yield fill
+
+    def copyto_scalar():
+        arr = np.empty(3, dtype=dtype)
+        np.copyto(arr, value, casting="unsafe")
+
+    yield copyto_scalar
+
+    def copyto():
+        arr = np.empty(3, dtype=dtype)
+        np.copyto(arr, np.array([value, value, value]), casting="unsafe")
+
+    yield copyto
+
+    def copyto_scalar_masked():
+        arr = np.empty(3, dtype=dtype)
+        np.copyto(arr, value, casting="unsafe",
+                  where=[True, False, True])
+
+    yield copyto_scalar_masked
+
+    def copyto_masked():
+        arr = np.empty(3, dtype=dtype)
+        np.copyto(arr, np.array([value, value, value]), casting="unsafe",
+                  where=[True, False, True])
+
+    yield copyto_masked
+
+    def direct_cast():
+        np.array([value, value, value]).astype(dtype)
+
+    yield direct_cast
+
+    def direct_cast_nd_strided():
+        arr = np.full((5, 5, 5), fill_value=value)[:, ::2, :]
+        arr.astype(dtype)
+
+    yield direct_cast_nd_strided
+
+    def boolean_array_assignment():
+        arr = np.empty(3, dtype=dtype)
+        arr[[True, False, True]] = np.array([value, value])
+
+    yield boolean_array_assignment
+
+    def integer_array_assignment():
+        arr = np.empty(3, dtype=dtype)
+        values = np.array([value, value])
+
+        arr[[0, 1]] = values
+
+    yield integer_array_assignment
+
+    def integer_array_assignment_with_subspace():
+        arr = np.empty((5, 3), dtype=dtype)
+        values = np.array([value, value, value])
+
+        arr[[0, 2]] = values
+
+    yield integer_array_assignment_with_subspace
+
+    def flat_assignment():
+        arr = np.empty((3,), dtype=dtype)
+        values = np.array([value, value, value])
+        arr.flat[:] = values
+
+    yield flat_assignment
+
+@pytest.mark.skipif(IS_WASM, reason="no wasm fp exception support")
+@pytest.mark.parametrize(["value", "dtype"], values_and_dtypes())
+@pytest.mark.filterwarnings("ignore::numpy.ComplexWarning")
+def test_floatingpoint_errors_casting(dtype, value):
+    dtype = np.dtype(dtype)
+    for operation in check_operations(dtype, value):
+        dtype = np.dtype(dtype)
+
+        match = "invalid" if dtype.kind in 'iu' else "overflow"
+        with pytest.warns(RuntimeWarning, match=match):
+            operation()
+
+        with np.errstate(all="raise"):
+            with pytest.raises(FloatingPointError, match=match):
+                operation()
+

.venv/lib/python3.11/site-packages/numpy/core/tests/test_cpu_features.py

@@ -0,0 +1,404 @@
+import sys, platform, re, pytest
+from numpy.core._multiarray_umath import (
+    __cpu_features__,
+    __cpu_baseline__,
+    __cpu_dispatch__,
+)
+import numpy as np
+import subprocess
+import pathlib
+import os
+import re
+
+def assert_features_equal(actual, desired, fname):
+    __tracebackhide__ = True  # Hide traceback for py.test
+    actual, desired = str(actual), str(desired)
+    if actual == desired:
+        return
+    detected = str(__cpu_features__).replace("'", "")
+    try:
+        with open("/proc/cpuinfo") as fd:
+            cpuinfo = fd.read(2048)
+    except Exception as err:
+        cpuinfo = str(err)
+
+    try:
+        import subprocess
+        auxv = subprocess.check_output(['/bin/true'], env=dict(LD_SHOW_AUXV="1"))
+        auxv = auxv.decode()
+    except Exception as err:
+        auxv = str(err)
+
+    import textwrap
+    error_report = textwrap.indent(
+"""
+###########################################
+### Extra debugging information
+###########################################
+-------------------------------------------
+--- NumPy Detections
+-------------------------------------------
+%s
+-------------------------------------------
+--- SYS / CPUINFO
+-------------------------------------------
+%s....
+-------------------------------------------
+--- SYS / AUXV
+-------------------------------------------
+%s
+""" % (detected, cpuinfo, auxv), prefix='\r')
+
+    raise AssertionError((
+        "Failure Detection\n"
+        " NAME: '%s'\n"
+        " ACTUAL: %s\n"
+        " DESIRED: %s\n"
+        "%s"
+    ) % (fname, actual, desired, error_report))
+
+def _text_to_list(txt):
+    out = txt.strip("][\n").replace("'", "").split(', ')
+    return None if out[0] == "" else out
+
+class AbstractTest:
+    features = []
+    features_groups = {}
+    features_map = {}
+    features_flags = set()
+
+    def load_flags(self):
+        # a hook
+        pass
+    def test_features(self):
+        self.load_flags()
+        for gname, features in self.features_groups.items():
+            test_features = [self.cpu_have(f) for f in features]
+            assert_features_equal(__cpu_features__.get(gname), all(test_features), gname)
+
+        for feature_name in self.features:
+            cpu_have = self.cpu_have(feature_name)
+            npy_have = __cpu_features__.get(feature_name)
+            assert_features_equal(npy_have, cpu_have, feature_name)
+
+    def cpu_have(self, feature_name):
+        map_names = self.features_map.get(feature_name, feature_name)
+        if isinstance(map_names, str):
+            return map_names in self.features_flags
+        for f in map_names:
+            if f in self.features_flags:
+                return True
+        return False
+
+    def load_flags_cpuinfo(self, magic_key):
+        self.features_flags = self.get_cpuinfo_item(magic_key)
+
+    def get_cpuinfo_item(self, magic_key):
+        values = set()
+        with open('/proc/cpuinfo') as fd:
+            for line in fd:
+                if not line.startswith(magic_key):
+                    continue
+                flags_value = [s.strip() for s in line.split(':', 1)]
+                if len(flags_value) == 2:
+                    values = values.union(flags_value[1].upper().split())
+        return values
+
+    def load_flags_auxv(self):
+        auxv = subprocess.check_output(['/bin/true'], env=dict(LD_SHOW_AUXV="1"))
+        for at in auxv.split(b'\n'):
+            if not at.startswith(b"AT_HWCAP"):
+                continue
+            hwcap_value = [s.strip() for s in at.split(b':', 1)]
+            if len(hwcap_value) == 2:
+                self.features_flags = self.features_flags.union(
+                    hwcap_value[1].upper().decode().split()
+                )
+
+@pytest.mark.skipif(
+    sys.platform == 'emscripten',
+    reason= (
+        "The subprocess module is not available on WASM platforms and"
+        " therefore this test class cannot be properly executed."
+    ),
+)
+class TestEnvPrivation:
+    cwd = pathlib.Path(__file__).parent.resolve()
+    env = os.environ.copy()
+    _enable = os.environ.pop('NPY_ENABLE_CPU_FEATURES', None)
+    _disable = os.environ.pop('NPY_DISABLE_CPU_FEATURES', None)
+    SUBPROCESS_ARGS = dict(cwd=cwd, capture_output=True, text=True, check=True)
+    unavailable_feats = [
+        feat for feat in __cpu_dispatch__ if not __cpu_features__[feat]
+    ]
+    UNAVAILABLE_FEAT = (
+        None if len(unavailable_feats) == 0
+        else unavailable_feats[0]
+    )
+    BASELINE_FEAT = None if len(__cpu_baseline__) == 0 else __cpu_baseline__[0]
+    SCRIPT = """
+def main():
+    from numpy.core._multiarray_umath import __cpu_features__, __cpu_dispatch__
+
+    detected = [feat for feat in __cpu_dispatch__ if __cpu_features__[feat]]
+    print(detected)
+
+if __name__ == "__main__":
+    main()
+    """
+
+    @pytest.fixture(autouse=True)
+    def setup_class(self, tmp_path_factory):
+        file = tmp_path_factory.mktemp("runtime_test_script")
+        file /= "_runtime_detect.py"
+        file.write_text(self.SCRIPT)
+        self.file = file
+        return
+
+    def _run(self):
+        return subprocess.run(
+            [sys.executable, self.file],
+            env=self.env,
+            **self.SUBPROCESS_ARGS,
+            )
+
+    # Helper function mimicing pytest.raises for subprocess call
+    def _expect_error(
+        self,
+        msg,
+        err_type,
+        no_error_msg="Failed to generate error"
+    ):
+        try:
+            self._run()
+        except subprocess.CalledProcessError as e:
+            assertion_message = f"Expected: {msg}\nGot: {e.stderr}"
+            assert re.search(msg, e.stderr), assertion_message
+
+            assertion_message = (
+                f"Expected error of type: {err_type}; see full "
+                f"error:\n{e.stderr}"
+            )
+            assert re.search(err_type, e.stderr), assertion_message
+        else:
+            assert False, no_error_msg
+
+    def setup_method(self):
+        """Ensure that the environment is reset"""
+        self.env = os.environ.copy()
+        return
+
+    def test_runtime_feature_selection(self):
+        """
+        Ensure that when selecting `NPY_ENABLE_CPU_FEATURES`, only the
+        features exactly specified are dispatched.
+        """
+
+        # Capture runtime-enabled features
+        out = self._run()
+        non_baseline_features = _text_to_list(out.stdout)
+
+        if non_baseline_features is None:
+            pytest.skip(
+                "No dispatchable features outside of baseline detected."
+            )
+        feature = non_baseline_features[0]
+
+        # Capture runtime-enabled features when `NPY_ENABLE_CPU_FEATURES` is
+        # specified
+        self.env['NPY_ENABLE_CPU_FEATURES'] = feature
+        out = self._run()
+        enabled_features = _text_to_list(out.stdout)
+
+        # Ensure that only one feature is enabled, and it is exactly the one
+        # specified by `NPY_ENABLE_CPU_FEATURES`
+        assert set(enabled_features) == {feature}
+
+        if len(non_baseline_features) < 2:
+            pytest.skip("Only one non-baseline feature detected.")
+        # Capture runtime-enabled features when `NPY_ENABLE_CPU_FEATURES` is
+        # specified
+        self.env['NPY_ENABLE_CPU_FEATURES'] = ",".join(non_baseline_features)
+        out = self._run()
+        enabled_features = _text_to_list(out.stdout)
+
+        # Ensure that both features are enabled, and they are exactly the ones
+        # specified by `NPY_ENABLE_CPU_FEATURES`
+        assert set(enabled_features) == set(non_baseline_features)
+        return
+
+    @pytest.mark.parametrize("enabled, disabled",
+    [
+        ("feature", "feature"),
+        ("feature", "same"),
+    ])
+    def test_both_enable_disable_set(self, enabled, disabled):
+        """
+        Ensure that when both environment variables are set then an
+        ImportError is thrown
+        """
+        self.env['NPY_ENABLE_CPU_FEATURES'] = enabled
+        self.env['NPY_DISABLE_CPU_FEATURES'] = disabled
+        msg = "Both NPY_DISABLE_CPU_FEATURES and NPY_ENABLE_CPU_FEATURES"
+        err_type = "ImportError"
+        self._expect_error(msg, err_type)
+
+    @pytest.mark.skipif(
+        not __cpu_dispatch__,
+        reason=(
+            "NPY_*_CPU_FEATURES only parsed if "
+            "`__cpu_dispatch__` is non-empty"
+        )
+    )
+    @pytest.mark.parametrize("action", ["ENABLE", "DISABLE"])
+    def test_variable_too_long(self, action):
+        """
+        Test that an error is thrown if the environment variables are too long
+        to be processed. Current limit is 1024, but this may change later.
+        """
+        MAX_VAR_LENGTH = 1024
+        # Actual length is MAX_VAR_LENGTH + 1 due to null-termination
+        self.env[f'NPY_{action}_CPU_FEATURES'] = "t" * MAX_VAR_LENGTH
+        msg = (
+            f"Length of environment variable 'NPY_{action}_CPU_FEATURES' is "
+            f"{MAX_VAR_LENGTH + 1}, only {MAX_VAR_LENGTH} accepted"
+        )
+        err_type = "RuntimeError"
+        self._expect_error(msg, err_type)
+
+    @pytest.mark.skipif(
+        not __cpu_dispatch__,
+        reason=(
+            "NPY_*_CPU_FEATURES only parsed if "
+            "`__cpu_dispatch__` is non-empty"
+        )
+    )
+    def test_impossible_feature_disable(self):
+        """
+        Test that a RuntimeError is thrown if an impossible feature-disabling
+        request is made. This includes disabling a baseline feature.
+        """
+
+        if self.BASELINE_FEAT is None:
+            pytest.skip("There are no unavailable features to test with")
+        bad_feature = self.BASELINE_FEAT
+        self.env['NPY_DISABLE_CPU_FEATURES'] = bad_feature
+        msg = (
+            f"You cannot disable CPU feature '{bad_feature}', since it is "
+            "part of the baseline optimizations"
+        )
+        err_type = "RuntimeError"
+        self._expect_error(msg, err_type)
+
+    def test_impossible_feature_enable(self):
+        """
+        Test that a RuntimeError is thrown if an impossible feature-enabling
+        request is made. This includes enabling a feature not supported by the
+        machine, or disabling a baseline optimization.
+        """
+
+        if self.UNAVAILABLE_FEAT is None:
+            pytest.skip("There are no unavailable features to test with")
+        bad_feature = self.UNAVAILABLE_FEAT
+        self.env['NPY_ENABLE_CPU_FEATURES'] = bad_feature
+        msg = (
+            f"You cannot enable CPU features \\({bad_feature}\\), since "
+            "they are not supported by your machine."
+        )
+        err_type = "RuntimeError"
+        self._expect_error(msg, err_type)
+
+        # Ensure that only the bad feature gets reported
+        feats = f"{bad_feature}, {self.BASELINE_FEAT}"
+        self.env['NPY_ENABLE_CPU_FEATURES'] = feats
+        msg = (
+            f"You cannot enable CPU features \\({bad_feature}\\), since they "
+            "are not supported by your machine."
+        )
+        self._expect_error(msg, err_type)
+
+is_linux = sys.platform.startswith('linux')
+is_cygwin = sys.platform.startswith('cygwin')
+machine  = platform.machine()
+is_x86   = re.match("^(amd64|x86|i386|i686)", machine, re.IGNORECASE)
+@pytest.mark.skipif(
+    not (is_linux or is_cygwin) or not is_x86, reason="Only for Linux and x86"
+)
+class Test_X86_Features(AbstractTest):
+    features = [
+        "MMX", "SSE", "SSE2", "SSE3", "SSSE3", "SSE41", "POPCNT", "SSE42",
+        "AVX", "F16C", "XOP", "FMA4", "FMA3", "AVX2", "AVX512F", "AVX512CD",
+        "AVX512ER", "AVX512PF", "AVX5124FMAPS", "AVX5124VNNIW", "AVX512VPOPCNTDQ",
+        "AVX512VL", "AVX512BW", "AVX512DQ", "AVX512VNNI", "AVX512IFMA",
+        "AVX512VBMI", "AVX512VBMI2", "AVX512BITALG", "AVX512FP16",
+    ]
+    features_groups = dict(
+        AVX512_KNL = ["AVX512F", "AVX512CD", "AVX512ER", "AVX512PF"],
+        AVX512_KNM = ["AVX512F", "AVX512CD", "AVX512ER", "AVX512PF", "AVX5124FMAPS",
+                      "AVX5124VNNIW", "AVX512VPOPCNTDQ"],
+        AVX512_SKX = ["AVX512F", "AVX512CD", "AVX512BW", "AVX512DQ", "AVX512VL"],
+        AVX512_CLX = ["AVX512F", "AVX512CD", "AVX512BW", "AVX512DQ", "AVX512VL", "AVX512VNNI"],
+        AVX512_CNL = ["AVX512F", "AVX512CD", "AVX512BW", "AVX512DQ", "AVX512VL", "AVX512IFMA",
+                      "AVX512VBMI"],
+        AVX512_ICL = ["AVX512F", "AVX512CD", "AVX512BW", "AVX512DQ", "AVX512VL", "AVX512IFMA",
+                      "AVX512VBMI", "AVX512VNNI", "AVX512VBMI2", "AVX512BITALG", "AVX512VPOPCNTDQ"],
+        AVX512_SPR = ["AVX512F", "AVX512CD", "AVX512BW", "AVX512DQ",
+                      "AVX512VL", "AVX512IFMA", "AVX512VBMI", "AVX512VNNI",
+                      "AVX512VBMI2", "AVX512BITALG", "AVX512VPOPCNTDQ",
+                      "AVX512FP16"],
+    )
+    features_map = dict(
+        SSE3="PNI", SSE41="SSE4_1", SSE42="SSE4_2", FMA3="FMA",
+        AVX512VNNI="AVX512_VNNI", AVX512BITALG="AVX512_BITALG", AVX512VBMI2="AVX512_VBMI2",
+        AVX5124FMAPS="AVX512_4FMAPS", AVX5124VNNIW="AVX512_4VNNIW", AVX512VPOPCNTDQ="AVX512_VPOPCNTDQ",
+        AVX512FP16="AVX512_FP16",
+    )
+    def load_flags(self):
+        self.load_flags_cpuinfo("flags")
+
+is_power = re.match("^(powerpc|ppc)64", machine, re.IGNORECASE)
+@pytest.mark.skipif(not is_linux or not is_power, reason="Only for Linux and Power")
+class Test_POWER_Features(AbstractTest):
+    features = ["VSX", "VSX2", "VSX3", "VSX4"]
+    features_map = dict(VSX2="ARCH_2_07", VSX3="ARCH_3_00", VSX4="ARCH_3_1")
+
+    def load_flags(self):
+        self.load_flags_auxv()
+
+
+is_zarch = re.match("^(s390x)", machine, re.IGNORECASE)
+@pytest.mark.skipif(not is_linux or not is_zarch,
+                    reason="Only for Linux and IBM Z")
+class Test_ZARCH_Features(AbstractTest):
+    features = ["VX", "VXE", "VXE2"]
+
+    def load_flags(self):
+        self.load_flags_auxv()
+
+
+is_arm = re.match("^(arm|aarch64)", machine, re.IGNORECASE)
+@pytest.mark.skipif(not is_linux or not is_arm, reason="Only for Linux and ARM")
+class Test_ARM_Features(AbstractTest):
+    features = [
+        "NEON", "ASIMD", "FPHP", "ASIMDHP", "ASIMDDP", "ASIMDFHM"
+    ]
+    features_groups = dict(
+        NEON_FP16  = ["NEON", "HALF"],
+        NEON_VFPV4 = ["NEON", "VFPV4"],
+    )
+    def load_flags(self):
+        self.load_flags_cpuinfo("Features")
+        arch = self.get_cpuinfo_item("CPU architecture")
+        # in case of mounting virtual filesystem of aarch64 kernel
+        is_rootfs_v8 = int('0'+next(iter(arch))) > 7 if arch else 0
+        if  re.match("^(aarch64|AARCH64)", machine) or is_rootfs_v8:
+            self.features_map = dict(
+                NEON="ASIMD", HALF="ASIMD", VFPV4="ASIMD"
+            )
+        else:
+            self.features_map = dict(
+                # ELF auxiliary vector and /proc/cpuinfo on Linux kernel(armv8 aarch32)
+                # doesn't provide information about ASIMD, so we assume that ASIMD is supported
+                # if the kernel reports any one of the following ARM8 features.
+                ASIMD=("AES", "SHA1", "SHA2", "PMULL", "CRC32")
+            )

.venv/lib/python3.11/site-packages/numpy/core/tests/test_custom_dtypes.py

@@ -0,0 +1,253 @@
+import pytest
+
+import numpy as np
+from numpy.testing import assert_array_equal
+from numpy.core._multiarray_umath import (
+    _discover_array_parameters as discover_array_params, _get_sfloat_dtype)
+
+
+SF = _get_sfloat_dtype()
+
+
+class TestSFloat:
+    def _get_array(self, scaling, aligned=True):
+        if not aligned:
+            a = np.empty(3*8 + 1, dtype=np.uint8)[1:]
+            a = a.view(np.float64)
+            a[:] = [1., 2., 3.]
+        else:
+            a = np.array([1., 2., 3.])
+
+        a *= 1./scaling  # the casting code also uses the reciprocal.
+        return a.view(SF(scaling))
+
+    def test_sfloat_rescaled(self):
+        sf = SF(1.)
+        sf2 = sf.scaled_by(2.)
+        assert sf2.get_scaling() == 2.
+        sf6 = sf2.scaled_by(3.)
+        assert sf6.get_scaling() == 6.
+
+    def test_class_discovery(self):
+        # This does not test much, since we always discover the scaling as 1.
+        # But most of NumPy (when writing) does not understand DType classes
+        dt, _ = discover_array_params([1., 2., 3.], dtype=SF)
+        assert dt == SF(1.)
+
+    @pytest.mark.parametrize("scaling", [1., -1., 2.])
+    def test_scaled_float_from_floats(self, scaling):
+        a = np.array([1., 2., 3.], dtype=SF(scaling))
+
+        assert a.dtype.get_scaling() == scaling
+        assert_array_equal(scaling * a.view(np.float64), [1., 2., 3.])
+
+    def test_repr(self):
+        # Check the repr, mainly to cover the code paths:
+        assert repr(SF(scaling=1.)) == "_ScaledFloatTestDType(scaling=1.0)"
+
+    def test_dtype_name(self):
+        assert SF(1.).name == "_ScaledFloatTestDType64"
+
+    @pytest.mark.parametrize("scaling", [1., -1., 2.])
+    def test_sfloat_from_float(self, scaling):
+        a = np.array([1., 2., 3.]).astype(dtype=SF(scaling))
+
+        assert a.dtype.get_scaling() == scaling
+        assert_array_equal(scaling * a.view(np.float64), [1., 2., 3.])
+
+    @pytest.mark.parametrize("aligned", [True, False])
+    @pytest.mark.parametrize("scaling", [1., -1., 2.])
+    def test_sfloat_getitem(self, aligned, scaling):
+        a = self._get_array(1., aligned)
+        assert a.tolist() == [1., 2., 3.]
+
+    @pytest.mark.parametrize("aligned", [True, False])
+    def test_sfloat_casts(self, aligned):
+        a = self._get_array(1., aligned)
+
+        assert np.can_cast(a, SF(-1.), casting="equiv")
+        assert not np.can_cast(a, SF(-1.), casting="no")
+        na = a.astype(SF(-1.))
+        assert_array_equal(-1 * na.view(np.float64), a.view(np.float64))
+
+        assert np.can_cast(a, SF(2.), casting="same_kind")
+        assert not np.can_cast(a, SF(2.), casting="safe")
+        a2 = a.astype(SF(2.))
+        assert_array_equal(2 * a2.view(np.float64), a.view(np.float64))
+
+    @pytest.mark.parametrize("aligned", [True, False])
+    def test_sfloat_cast_internal_errors(self, aligned):
+        a = self._get_array(2e300, aligned)
+
+        with pytest.raises(TypeError,
+                match="error raised inside the core-loop: non-finite factor!"):
+            a.astype(SF(2e-300))
+
+    def test_sfloat_promotion(self):
+        assert np.result_type(SF(2.), SF(3.)) == SF(3.)
+        assert np.result_type(SF(3.), SF(2.)) == SF(3.)
+        # Float64 -> SF(1.) and then promotes normally, so both of this work:
+        assert np.result_type(SF(3.), np.float64) == SF(3.)
+        assert np.result_type(np.float64, SF(0.5)) == SF(1.)
+
+        # Test an undefined promotion:
+        with pytest.raises(TypeError):
+            np.result_type(SF(1.), np.int64)
+
+    def test_basic_multiply(self):
+        a = self._get_array(2.)
+        b = self._get_array(4.)
+
+        res = a * b
+        # multiplies dtype scaling and content separately:
+        assert res.dtype.get_scaling() == 8.
+        expected_view = a.view(np.float64) * b.view(np.float64)
+        assert_array_equal(res.view(np.float64), expected_view)
+
+    def test_possible_and_impossible_reduce(self):
+        # For reductions to work, the first and last operand must have the
+        # same dtype.  For this parametric DType that is not necessarily true.
+        a = self._get_array(2.)
+        # Addition reductin works (as of writing requires to pass initial
+        # because setting a scaled-float from the default `0` fails).
+        res = np.add.reduce(a, initial=0.)
+        assert res == a.astype(np.float64).sum()
+
+        # But each multiplication changes the factor, so a reduction is not
+        # possible (the relaxed version of the old refusal to handle any
+        # flexible dtype).
+        with pytest.raises(TypeError,
+                match="the resolved dtypes are not compatible"):
+            np.multiply.reduce(a)
+
+    def test_basic_ufunc_at(self):
+        float_a = np.array([1., 2., 3.])
+        b = self._get_array(2.)
+
+        float_b = b.view(np.float64).copy()
+        np.multiply.at(float_b, [1, 1, 1], float_a)
+        np.multiply.at(b, [1, 1, 1], float_a)
+
+        assert_array_equal(b.view(np.float64), float_b)
+
+    def test_basic_multiply_promotion(self):
+        float_a = np.array([1., 2., 3.])
+        b = self._get_array(2.)
+
+        res1 = float_a * b
+        res2 = b * float_a
+
+        # one factor is one, so we get the factor of b:
+        assert res1.dtype == res2.dtype == b.dtype
+        expected_view = float_a * b.view(np.float64)
+        assert_array_equal(res1.view(np.float64), expected_view)
+        assert_array_equal(res2.view(np.float64), expected_view)
+
+        # Check that promotion works when `out` is used:
+        np.multiply(b, float_a, out=res2)
+        with pytest.raises(TypeError):
+            # The promoter accepts this (maybe it should not), but the SFloat
+            # result cannot be cast to integer:
+            np.multiply(b, float_a, out=np.arange(3))
+
+    def test_basic_addition(self):
+        a = self._get_array(2.)
+        b = self._get_array(4.)
+
+        res = a + b
+        # addition uses the type promotion rules for the result:
+        assert res.dtype == np.result_type(a.dtype, b.dtype)
+        expected_view = (a.astype(res.dtype).view(np.float64) +
+                         b.astype(res.dtype).view(np.float64))
+        assert_array_equal(res.view(np.float64), expected_view)
+
+    def test_addition_cast_safety(self):
+        """The addition method is special for the scaled float, because it
+        includes the "cast" between different factors, thus cast-safety
+        is influenced by the implementation.
+        """
+        a = self._get_array(2.)
+        b = self._get_array(-2.)
+        c = self._get_array(3.)
+
+        # sign change is "equiv":
+        np.add(a, b, casting="equiv")
+        with pytest.raises(TypeError):
+            np.add(a, b, casting="no")
+
+        # Different factor is "same_kind" (default) so check that "safe" fails
+        with pytest.raises(TypeError):
+            np.add(a, c, casting="safe")
+
+        # Check that casting the output fails also (done by the ufunc here)
+        with pytest.raises(TypeError):
+            np.add(a, a, out=c, casting="safe")
+
+    @pytest.mark.parametrize("ufunc",
+            [np.logical_and, np.logical_or, np.logical_xor])
+    def test_logical_ufuncs_casts_to_bool(self, ufunc):
+        a = self._get_array(2.)
+        a[0] = 0.  # make sure first element is considered False.
+
+        float_equiv = a.astype(float)
+        expected = ufunc(float_equiv, float_equiv)
+        res = ufunc(a, a)
+        assert_array_equal(res, expected)
+
+        # also check that the same works for reductions:
+        expected = ufunc.reduce(float_equiv)
+        res = ufunc.reduce(a)
+        assert_array_equal(res, expected)
+
+        # The output casting does not match the bool, bool -> bool loop:
+        with pytest.raises(TypeError):
+            ufunc(a, a, out=np.empty(a.shape, dtype=int), casting="equiv")
+
+    def test_wrapped_and_wrapped_reductions(self):
+        a = self._get_array(2.)
+        float_equiv = a.astype(float)
+
+        expected = np.hypot(float_equiv, float_equiv)
+        res = np.hypot(a, a)
+        assert res.dtype == a.dtype
+        res_float = res.view(np.float64) * 2
+        assert_array_equal(res_float, expected)
+
+        # Also check reduction (keepdims, due to incorrect getitem)
+        res = np.hypot.reduce(a, keepdims=True)
+        assert res.dtype == a.dtype
+        expected = np.hypot.reduce(float_equiv, keepdims=True)
+        assert res.view(np.float64) * 2 == expected
+
+    def test_astype_class(self):
+        # Very simple test that we accept `.astype()` also on the class.
+        # ScaledFloat always returns the default descriptor, but it does
+        # check the relevant code paths.
+        arr = np.array([1., 2., 3.], dtype=object)
+
+        res = arr.astype(SF)  # passing the class class
+        expected = arr.astype(SF(1.))  # above will have discovered 1. scaling
+        assert_array_equal(res.view(np.float64), expected.view(np.float64))
+
+    def test_creation_class(self):
+        arr1 = np.array([1., 2., 3.], dtype=SF)
+        assert arr1.dtype == SF(1.)
+        arr2 = np.array([1., 2., 3.], dtype=SF(1.))
+        assert_array_equal(arr1.view(np.float64), arr2.view(np.float64))
+
+
+def test_type_pickle():
+    # can't actually unpickle, but we can pickle (if in namespace)
+    import pickle
+
+    np._ScaledFloatTestDType = SF
+
+    s = pickle.dumps(SF)
+    res = pickle.loads(s)
+    assert res is SF
+
+    del np._ScaledFloatTestDType
+
+
+def test_is_numeric():
+    assert SF._is_numeric

.venv/lib/python3.11/site-packages/numpy/core/tests/test_defchararray.py

@@ -0,0 +1,686 @@
+import pytest
+
+import numpy as np
+from numpy.core.multiarray import _vec_string
+from numpy.testing import (
+    assert_, assert_equal, assert_array_equal, assert_raises,
+    assert_raises_regex
+    )
+
+kw_unicode_true = {'unicode': True}  # make 2to3 work properly
+kw_unicode_false = {'unicode': False}
+
+class TestBasic:
+    def test_from_object_array(self):
+        A = np.array([['abc', 2],
+                      ['long   ', '0123456789']], dtype='O')
+        B = np.char.array(A)
+        assert_equal(B.dtype.itemsize, 10)
+        assert_array_equal(B, [[b'abc', b'2'],
+                               [b'long', b'0123456789']])
+
+    def test_from_object_array_unicode(self):
+        A = np.array([['abc', 'Sigma \u03a3'],
+                      ['long   ', '0123456789']], dtype='O')
+        assert_raises(ValueError, np.char.array, (A,))
+        B = np.char.array(A, **kw_unicode_true)
+        assert_equal(B.dtype.itemsize, 10 * np.array('a', 'U').dtype.itemsize)
+        assert_array_equal(B, [['abc', 'Sigma \u03a3'],
+                               ['long', '0123456789']])
+
+    def test_from_string_array(self):
+        A = np.array([[b'abc', b'foo'],
+                      [b'long   ', b'0123456789']])
+        assert_equal(A.dtype.type, np.bytes_)
+        B = np.char.array(A)
+        assert_array_equal(B, A)
+        assert_equal(B.dtype, A.dtype)
+        assert_equal(B.shape, A.shape)
+        B[0, 0] = 'changed'
+        assert_(B[0, 0] != A[0, 0])
+        C = np.char.asarray(A)
+        assert_array_equal(C, A)
+        assert_equal(C.dtype, A.dtype)
+        C[0, 0] = 'changed again'
+        assert_(C[0, 0] != B[0, 0])
+        assert_(C[0, 0] == A[0, 0])
+
+    def test_from_unicode_array(self):
+        A = np.array([['abc', 'Sigma \u03a3'],
+                      ['long   ', '0123456789']])
+        assert_equal(A.dtype.type, np.str_)
+        B = np.char.array(A)
+        assert_array_equal(B, A)
+        assert_equal(B.dtype, A.dtype)
+        assert_equal(B.shape, A.shape)
+        B = np.char.array(A, **kw_unicode_true)
+        assert_array_equal(B, A)
+        assert_equal(B.dtype, A.dtype)
+        assert_equal(B.shape, A.shape)
+
+        def fail():
+            np.char.array(A, **kw_unicode_false)
+
+        assert_raises(UnicodeEncodeError, fail)
+
+    def test_unicode_upconvert(self):
+        A = np.char.array(['abc'])
+        B = np.char.array(['\u03a3'])
+        assert_(issubclass((A + B).dtype.type, np.str_))
+
+    def test_from_string(self):
+        A = np.char.array(b'abc')
+        assert_equal(len(A), 1)
+        assert_equal(len(A[0]), 3)
+        assert_(issubclass(A.dtype.type, np.bytes_))
+
+    def test_from_unicode(self):
+        A = np.char.array('\u03a3')
+        assert_equal(len(A), 1)
+        assert_equal(len(A[0]), 1)
+        assert_equal(A.itemsize, 4)
+        assert_(issubclass(A.dtype.type, np.str_))
+
+class TestVecString:
+    def test_non_existent_method(self):
+
+        def fail():
+            _vec_string('a', np.bytes_, 'bogus')
+
+        assert_raises(AttributeError, fail)
+
+    def test_non_string_array(self):
+
+        def fail():
+            _vec_string(1, np.bytes_, 'strip')
+
+        assert_raises(TypeError, fail)
+
+    def test_invalid_args_tuple(self):
+
+        def fail():
+            _vec_string(['a'], np.bytes_, 'strip', 1)
+
+        assert_raises(TypeError, fail)
+
+    def test_invalid_type_descr(self):
+
+        def fail():
+            _vec_string(['a'], 'BOGUS', 'strip')
+
+        assert_raises(TypeError, fail)
+
+    def test_invalid_function_args(self):
+
+        def fail():
+            _vec_string(['a'], np.bytes_, 'strip', (1,))
+
+        assert_raises(TypeError, fail)
+
+    def test_invalid_result_type(self):
+
+        def fail():
+            _vec_string(['a'], np.int_, 'strip')
+
+        assert_raises(TypeError, fail)
+
+    def test_broadcast_error(self):
+
+        def fail():
+            _vec_string([['abc', 'def']], np.int_, 'find', (['a', 'd', 'j'],))
+
+        assert_raises(ValueError, fail)
+
+
+class TestWhitespace:
+    def setup_method(self):
+        self.A = np.array([['abc ', '123  '],
+                           ['789 ', 'xyz ']]).view(np.chararray)
+        self.B = np.array([['abc', '123'],
+                           ['789', 'xyz']]).view(np.chararray)
+
+    def test1(self):
+        assert_(np.all(self.A == self.B))
+        assert_(np.all(self.A >= self.B))
+        assert_(np.all(self.A <= self.B))
+        assert_(not np.any(self.A > self.B))
+        assert_(not np.any(self.A < self.B))
+        assert_(not np.any(self.A != self.B))
+
+class TestChar:
+    def setup_method(self):
+        self.A = np.array('abc1', dtype='c').view(np.chararray)
+
+    def test_it(self):
+        assert_equal(self.A.shape, (4,))
+        assert_equal(self.A.upper()[:2].tobytes(), b'AB')
+
+class TestComparisons:
+    def setup_method(self):
+        self.A = np.array([['abc', '123'],
+                           ['789', 'xyz']]).view(np.chararray)
+        self.B = np.array([['efg', '123  '],
+                           ['051', 'tuv']]).view(np.chararray)
+
+    def test_not_equal(self):
+        assert_array_equal((self.A != self.B), [[True, False], [True, True]])
+
+    def test_equal(self):
+        assert_array_equal((self.A == self.B), [[False, True], [False, False]])
+
+    def test_greater_equal(self):
+        assert_array_equal((self.A >= self.B), [[False, True], [True, True]])
+
+    def test_less_equal(self):
+        assert_array_equal((self.A <= self.B), [[True, True], [False, False]])
+
+    def test_greater(self):
+        assert_array_equal((self.A > self.B), [[False, False], [True, True]])
+
+    def test_less(self):
+        assert_array_equal((self.A < self.B), [[True, False], [False, False]])
+
+    def test_type(self):
+        out1 = np.char.equal(self.A, self.B)
+        out2 = np.char.equal('a', 'a')
+        assert_(isinstance(out1, np.ndarray))
+        assert_(isinstance(out2, np.ndarray))
+
+class TestComparisonsMixed1(TestComparisons):
+    """Ticket #1276"""
+
+    def setup_method(self):
+        TestComparisons.setup_method(self)
+        self.B = np.array([['efg', '123  '],
+                           ['051', 'tuv']], np.str_).view(np.chararray)
+
+class TestComparisonsMixed2(TestComparisons):
+    """Ticket #1276"""
+
+    def setup_method(self):
+        TestComparisons.setup_method(self)
+        self.A = np.array([['abc', '123'],
+                           ['789', 'xyz']], np.str_).view(np.chararray)
+
+class TestInformation:
+    def setup_method(self):
+        self.A = np.array([[' abc ', ''],
+                           ['12345', 'MixedCase'],
+                           ['123 \t 345 \0 ', 'UPPER']]).view(np.chararray)
+        self.B = np.array([[' \u03a3 ', ''],
+                           ['12345', 'MixedCase'],
+                           ['123 \t 345 \0 ', 'UPPER']]).view(np.chararray)
+
+    def test_len(self):
+        assert_(issubclass(np.char.str_len(self.A).dtype.type, np.integer))
+        assert_array_equal(np.char.str_len(self.A), [[5, 0], [5, 9], [12, 5]])
+        assert_array_equal(np.char.str_len(self.B), [[3, 0], [5, 9], [12, 5]])
+
+    def test_count(self):
+        assert_(issubclass(self.A.count('').dtype.type, np.integer))
+        assert_array_equal(self.A.count('a'), [[1, 0], [0, 1], [0, 0]])
+        assert_array_equal(self.A.count('123'), [[0, 0], [1, 0], [1, 0]])
+        # Python doesn't seem to like counting NULL characters
+        # assert_array_equal(self.A.count('\0'), [[0, 0], [0, 0], [1, 0]])
+        assert_array_equal(self.A.count('a', 0, 2), [[1, 0], [0, 0], [0, 0]])
+        assert_array_equal(self.B.count('a'), [[0, 0], [0, 1], [0, 0]])
+        assert_array_equal(self.B.count('123'), [[0, 0], [1, 0], [1, 0]])
+        # assert_array_equal(self.B.count('\0'), [[0, 0], [0, 0], [1, 0]])
+
+    def test_endswith(self):
+        assert_(issubclass(self.A.endswith('').dtype.type, np.bool_))
+        assert_array_equal(self.A.endswith(' '), [[1, 0], [0, 0], [1, 0]])
+        assert_array_equal(self.A.endswith('3', 0, 3), [[0, 0], [1, 0], [1, 0]])
+
+        def fail():
+            self.A.endswith('3', 'fdjk')
+
+        assert_raises(TypeError, fail)
+
+    def test_find(self):
+        assert_(issubclass(self.A.find('a').dtype.type, np.integer))
+        assert_array_equal(self.A.find('a'), [[1, -1], [-1, 6], [-1, -1]])
+        assert_array_equal(self.A.find('3'), [[-1, -1], [2, -1], [2, -1]])
+        assert_array_equal(self.A.find('a', 0, 2), [[1, -1], [-1, -1], [-1, -1]])
+        assert_array_equal(self.A.find(['1', 'P']), [[-1, -1], [0, -1], [0, 1]])
+
+    def test_index(self):
+
+        def fail():
+            self.A.index('a')
+
+        assert_raises(ValueError, fail)
+        assert_(np.char.index('abcba', 'b') == 1)
+        assert_(issubclass(np.char.index('abcba', 'b').dtype.type, np.integer))
+
+    def test_isalnum(self):
+        assert_(issubclass(self.A.isalnum().dtype.type, np.bool_))
+        assert_array_equal(self.A.isalnum(), [[False, False], [True, True], [False, True]])
+
+    def test_isalpha(self):
+        assert_(issubclass(self.A.isalpha().dtype.type, np.bool_))
+        assert_array_equal(self.A.isalpha(), [[False, False], [False, True], [False, True]])
+
+    def test_isdigit(self):
+        assert_(issubclass(self.A.isdigit().dtype.type, np.bool_))
+        assert_array_equal(self.A.isdigit(), [[False, False], [True, False], [False, False]])
+
+    def test_islower(self):
+        assert_(issubclass(self.A.islower().dtype.type, np.bool_))
+        assert_array_equal(self.A.islower(), [[True, False], [False, False], [False, False]])
+
+    def test_isspace(self):
+        assert_(issubclass(self.A.isspace().dtype.type, np.bool_))
+        assert_array_equal(self.A.isspace(), [[False, False], [False, False], [False, False]])
+
+    def test_istitle(self):
+        assert_(issubclass(self.A.istitle().dtype.type, np.bool_))
+        assert_array_equal(self.A.istitle(), [[False, False], [False, False], [False, False]])
+
+    def test_isupper(self):
+        assert_(issubclass(self.A.isupper().dtype.type, np.bool_))
+        assert_array_equal(self.A.isupper(), [[False, False], [False, False], [False, True]])
+
+    def test_rfind(self):
+        assert_(issubclass(self.A.rfind('a').dtype.type, np.integer))
+        assert_array_equal(self.A.rfind('a'), [[1, -1], [-1, 6], [-1, -1]])
+        assert_array_equal(self.A.rfind('3'), [[-1, -1], [2, -1], [6, -1]])
+        assert_array_equal(self.A.rfind('a', 0, 2), [[1, -1], [-1, -1], [-1, -1]])
+        assert_array_equal(self.A.rfind(['1', 'P']), [[-1, -1], [0, -1], [0, 2]])
+
+    def test_rindex(self):
+
+        def fail():
+            self.A.rindex('a')
+
+        assert_raises(ValueError, fail)
+        assert_(np.char.rindex('abcba', 'b') == 3)
+        assert_(issubclass(np.char.rindex('abcba', 'b').dtype.type, np.integer))
+
+    def test_startswith(self):
+        assert_(issubclass(self.A.startswith('').dtype.type, np.bool_))
+        assert_array_equal(self.A.startswith(' '), [[1, 0], [0, 0], [0, 0]])
+        assert_array_equal(self.A.startswith('1', 0, 3), [[0, 0], [1, 0], [1, 0]])
+
+        def fail():
+            self.A.startswith('3', 'fdjk')
+
+        assert_raises(TypeError, fail)
+
+
+class TestMethods:
+    def setup_method(self):
+        self.A = np.array([[' abc ', ''],
+                           ['12345', 'MixedCase'],
+                           ['123 \t 345 \0 ', 'UPPER']],
+                          dtype='S').view(np.chararray)
+        self.B = np.array([[' \u03a3 ', ''],
+                           ['12345', 'MixedCase'],
+                           ['123 \t 345 \0 ', 'UPPER']]).view(np.chararray)
+
+    def test_capitalize(self):
+        tgt = [[b' abc ', b''],
+               [b'12345', b'Mixedcase'],
+               [b'123 \t 345 \0 ', b'Upper']]
+        assert_(issubclass(self.A.capitalize().dtype.type, np.bytes_))
+        assert_array_equal(self.A.capitalize(), tgt)
+
+        tgt = [[' \u03c3 ', ''],
+               ['12345', 'Mixedcase'],
+               ['123 \t 345 \0 ', 'Upper']]
+        assert_(issubclass(self.B.capitalize().dtype.type, np.str_))
+        assert_array_equal(self.B.capitalize(), tgt)
+
+    def test_center(self):
+        assert_(issubclass(self.A.center(10).dtype.type, np.bytes_))
+        C = self.A.center([10, 20])
+        assert_array_equal(np.char.str_len(C), [[10, 20], [10, 20], [12, 20]])
+
+        C = self.A.center(20, b'#')
+        assert_(np.all(C.startswith(b'#')))
+        assert_(np.all(C.endswith(b'#')))
+
+        C = np.char.center(b'FOO', [[10, 20], [15, 8]])
+        tgt = [[b'   FOO    ', b'        FOO         '],
+               [b'      FOO      ', b'  FOO   ']]
+        assert_(issubclass(C.dtype.type, np.bytes_))
+        assert_array_equal(C, tgt)
+
+    def test_decode(self):
+        A = np.char.array([b'\\u03a3'])
+        assert_(A.decode('unicode-escape')[0] == '\u03a3')
+
+    def test_encode(self):
+        B = self.B.encode('unicode_escape')
+        assert_(B[0][0] == str(' \\u03a3 ').encode('latin1'))
+
+    def test_expandtabs(self):
+        T = self.A.expandtabs()
+        assert_(T[2, 0] == b'123      345 \0')
+
+    def test_join(self):
+        # NOTE: list(b'123') == [49, 50, 51]
+        #       so that b','.join(b'123') results to an error on Py3
+        A0 = self.A.decode('ascii')
+
+        A = np.char.join([',', '#'], A0)
+        assert_(issubclass(A.dtype.type, np.str_))
+        tgt = np.array([[' ,a,b,c, ', ''],
+                        ['1,2,3,4,5', 'M#i#x#e#d#C#a#s#e'],
+                        ['1,2,3, ,\t, ,3,4,5, ,\x00, ', 'U#P#P#E#R']])
+        assert_array_equal(np.char.join([',', '#'], A0), tgt)
+
+    def test_ljust(self):
+        assert_(issubclass(self.A.ljust(10).dtype.type, np.bytes_))
+
+        C = self.A.ljust([10, 20])
+        assert_array_equal(np.char.str_len(C), [[10, 20], [10, 20], [12, 20]])
+
+        C = self.A.ljust(20, b'#')
+        assert_array_equal(C.startswith(b'#'), [
+                [False, True], [False, False], [False, False]])
+        assert_(np.all(C.endswith(b'#')))
+
+        C = np.char.ljust(b'FOO', [[10, 20], [15, 8]])
+        tgt = [[b'FOO       ', b'FOO                 '],
+               [b'FOO            ', b'FOO     ']]
+        assert_(issubclass(C.dtype.type, np.bytes_))
+        assert_array_equal(C, tgt)
+
+    def test_lower(self):
+        tgt = [[b' abc ', b''],
+               [b'12345', b'mixedcase'],
+               [b'123 \t 345 \0 ', b'upper']]
+        assert_(issubclass(self.A.lower().dtype.type, np.bytes_))
+        assert_array_equal(self.A.lower(), tgt)
+
+        tgt = [[' \u03c3 ', ''],
+               ['12345', 'mixedcase'],
+               ['123 \t 345 \0 ', 'upper']]
+        assert_(issubclass(self.B.lower().dtype.type, np.str_))
+        assert_array_equal(self.B.lower(), tgt)
+
+    def test_lstrip(self):
+        tgt = [[b'abc ', b''],
+               [b'12345', b'MixedCase'],
+               [b'123 \t 345 \0 ', b'UPPER']]
+        assert_(issubclass(self.A.lstrip().dtype.type, np.bytes_))
+        assert_array_equal(self.A.lstrip(), tgt)
+
+        tgt = [[b' abc', b''],
+               [b'2345', b'ixedCase'],
+               [b'23 \t 345 \x00', b'UPPER']]
+        assert_array_equal(self.A.lstrip([b'1', b'M']), tgt)
+
+        tgt = [['\u03a3 ', ''],
+               ['12345', 'MixedCase'],
+               ['123 \t 345 \0 ', 'UPPER']]
+        assert_(issubclass(self.B.lstrip().dtype.type, np.str_))
+        assert_array_equal(self.B.lstrip(), tgt)
+
+    def test_partition(self):
+        P = self.A.partition([b'3', b'M'])
+        tgt = [[(b' abc ', b'', b''), (b'', b'', b'')],
+               [(b'12', b'3', b'45'), (b'', b'M', b'ixedCase')],
+               [(b'12', b'3', b' \t 345 \0 '), (b'UPPER', b'', b'')]]
+        assert_(issubclass(P.dtype.type, np.bytes_))
+        assert_array_equal(P, tgt)
+
+    def test_replace(self):
+        R = self.A.replace([b'3', b'a'],
+                           [b'##########', b'@'])
+        tgt = [[b' abc ', b''],
+               [b'12##########45', b'MixedC@se'],
+               [b'12########## \t ##########45 \x00', b'UPPER']]
+        assert_(issubclass(R.dtype.type, np.bytes_))
+        assert_array_equal(R, tgt)
+
+    def test_rjust(self):
+        assert_(issubclass(self.A.rjust(10).dtype.type, np.bytes_))
+
+        C = self.A.rjust([10, 20])
+        assert_array_equal(np.char.str_len(C), [[10, 20], [10, 20], [12, 20]])
+
+        C = self.A.rjust(20, b'#')
+        assert_(np.all(C.startswith(b'#')))
+        assert_array_equal(C.endswith(b'#'),
+                           [[False, True], [False, False], [False, False]])
+
+        C = np.char.rjust(b'FOO', [[10, 20], [15, 8]])
+        tgt = [[b'       FOO', b'                 FOO'],
+               [b'            FOO', b'     FOO']]
+        assert_(issubclass(C.dtype.type, np.bytes_))
+        assert_array_equal(C, tgt)
+
+    def test_rpartition(self):
+        P = self.A.rpartition([b'3', b'M'])
+        tgt = [[(b'', b'', b' abc '), (b'', b'', b'')],
+               [(b'12', b'3', b'45'), (b'', b'M', b'ixedCase')],
+               [(b'123 \t ', b'3', b'45 \0 '), (b'', b'', b'UPPER')]]
+        assert_(issubclass(P.dtype.type, np.bytes_))
+        assert_array_equal(P, tgt)
+
+    def test_rsplit(self):
+        A = self.A.rsplit(b'3')
+        tgt = [[[b' abc '], [b'']],
+               [[b'12', b'45'], [b'MixedCase']],
+               [[b'12', b' \t ', b'45 \x00 '], [b'UPPER']]]
+        assert_(issubclass(A.dtype.type, np.object_))
+        assert_equal(A.tolist(), tgt)
+
+    def test_rstrip(self):
+        assert_(issubclass(self.A.rstrip().dtype.type, np.bytes_))
+
+        tgt = [[b' abc', b''],
+               [b'12345', b'MixedCase'],
+               [b'123 \t 345', b'UPPER']]
+        assert_array_equal(self.A.rstrip(), tgt)
+
+        tgt = [[b' abc ', b''],
+               [b'1234', b'MixedCase'],
+               [b'123 \t 345 \x00', b'UPP']
+               ]
+        assert_array_equal(self.A.rstrip([b'5', b'ER']), tgt)
+
+        tgt = [[' \u03a3', ''],
+               ['12345', 'MixedCase'],
+               ['123 \t 345', 'UPPER']]
+        assert_(issubclass(self.B.rstrip().dtype.type, np.str_))
+        assert_array_equal(self.B.rstrip(), tgt)
+
+    def test_strip(self):
+        tgt = [[b'abc', b''],
+               [b'12345', b'MixedCase'],
+               [b'123 \t 345', b'UPPER']]
+        assert_(issubclass(self.A.strip().dtype.type, np.bytes_))
+        assert_array_equal(self.A.strip(), tgt)
+
+        tgt = [[b' abc ', b''],
+               [b'234', b'ixedCas'],
+               [b'23 \t 345 \x00', b'UPP']]
+        assert_array_equal(self.A.strip([b'15', b'EReM']), tgt)
+
+        tgt = [['\u03a3', ''],
+               ['12345', 'MixedCase'],
+               ['123 \t 345', 'UPPER']]
+        assert_(issubclass(self.B.strip().dtype.type, np.str_))
+        assert_array_equal(self.B.strip(), tgt)
+
+    def test_split(self):
+        A = self.A.split(b'3')
+        tgt = [
+               [[b' abc '], [b'']],
+               [[b'12', b'45'], [b'MixedCase']],
+               [[b'12', b' \t ', b'45 \x00 '], [b'UPPER']]]
+        assert_(issubclass(A.dtype.type, np.object_))
+        assert_equal(A.tolist(), tgt)
+
+    def test_splitlines(self):
+        A = np.char.array(['abc\nfds\nwer']).splitlines()
+        assert_(issubclass(A.dtype.type, np.object_))
+        assert_(A.shape == (1,))
+        assert_(len(A[0]) == 3)
+
+    def test_swapcase(self):
+        tgt = [[b' ABC ', b''],
+               [b'12345', b'mIXEDcASE'],
+               [b'123 \t 345 \0 ', b'upper']]
+        assert_(issubclass(self.A.swapcase().dtype.type, np.bytes_))
+        assert_array_equal(self.A.swapcase(), tgt)
+
+        tgt = [[' \u03c3 ', ''],
+               ['12345', 'mIXEDcASE'],
+               ['123 \t 345 \0 ', 'upper']]
+        assert_(issubclass(self.B.swapcase().dtype.type, np.str_))
+        assert_array_equal(self.B.swapcase(), tgt)
+
+    def test_title(self):
+        tgt = [[b' Abc ', b''],
+               [b'12345', b'Mixedcase'],
+               [b'123 \t 345 \0 ', b'Upper']]
+        assert_(issubclass(self.A.title().dtype.type, np.bytes_))
+        assert_array_equal(self.A.title(), tgt)
+
+        tgt = [[' \u03a3 ', ''],
+               ['12345', 'Mixedcase'],
+               ['123 \t 345 \0 ', 'Upper']]
+        assert_(issubclass(self.B.title().dtype.type, np.str_))
+        assert_array_equal(self.B.title(), tgt)
+
+    def test_upper(self):
+        tgt = [[b' ABC ', b''],
+               [b'12345', b'MIXEDCASE'],
+               [b'123 \t 345 \0 ', b'UPPER']]
+        assert_(issubclass(self.A.upper().dtype.type, np.bytes_))
+        assert_array_equal(self.A.upper(), tgt)
+
+        tgt = [[' \u03a3 ', ''],
+               ['12345', 'MIXEDCASE'],
+               ['123 \t 345 \0 ', 'UPPER']]
+        assert_(issubclass(self.B.upper().dtype.type, np.str_))
+        assert_array_equal(self.B.upper(), tgt)
+
+    def test_isnumeric(self):
+
+        def fail():
+            self.A.isnumeric()
+
+        assert_raises(TypeError, fail)
+        assert_(issubclass(self.B.isnumeric().dtype.type, np.bool_))
+        assert_array_equal(self.B.isnumeric(), [
+                [False, False], [True, False], [False, False]])
+
+    def test_isdecimal(self):
+
+        def fail():
+            self.A.isdecimal()
+
+        assert_raises(TypeError, fail)
+        assert_(issubclass(self.B.isdecimal().dtype.type, np.bool_))
+        assert_array_equal(self.B.isdecimal(), [
+                [False, False], [True, False], [False, False]])
+
+
+class TestOperations:
+    def setup_method(self):
+        self.A = np.array([['abc', '123'],
+                           ['789', 'xyz']]).view(np.chararray)
+        self.B = np.array([['efg', '456'],
+                           ['051', 'tuv']]).view(np.chararray)
+
+    def test_add(self):
+        AB = np.array([['abcefg', '123456'],
+                       ['789051', 'xyztuv']]).view(np.chararray)
+        assert_array_equal(AB, (self.A + self.B))
+        assert_(len((self.A + self.B)[0][0]) == 6)
+
+    def test_radd(self):
+        QA = np.array([['qabc', 'q123'],
+                       ['q789', 'qxyz']]).view(np.chararray)
+        assert_array_equal(QA, ('q' + self.A))
+
+    def test_mul(self):
+        A = self.A
+        for r in (2, 3, 5, 7, 197):
+            Ar = np.array([[A[0, 0]*r, A[0, 1]*r],
+                           [A[1, 0]*r, A[1, 1]*r]]).view(np.chararray)
+
+            assert_array_equal(Ar, (self.A * r))
+
+        for ob in [object(), 'qrs']:
+            with assert_raises_regex(ValueError,
+                                     'Can only multiply by integers'):
+                A*ob
+
+    def test_rmul(self):
+        A = self.A
+        for r in (2, 3, 5, 7, 197):
+            Ar = np.array([[A[0, 0]*r, A[0, 1]*r],
+                           [A[1, 0]*r, A[1, 1]*r]]).view(np.chararray)
+            assert_array_equal(Ar, (r * self.A))
+
+        for ob in [object(), 'qrs']:
+            with assert_raises_regex(ValueError,
+                                     'Can only multiply by integers'):
+                ob * A
+
+    def test_mod(self):
+        """Ticket #856"""
+        F = np.array([['%d', '%f'], ['%s', '%r']]).view(np.chararray)
+        C = np.array([[3, 7], [19, 1]])
+        FC = np.array([['3', '7.000000'],
+                       ['19', '1']]).view(np.chararray)
+        assert_array_equal(FC, F % C)
+
+        A = np.array([['%.3f', '%d'], ['%s', '%r']]).view(np.chararray)
+        A1 = np.array([['1.000', '1'], ['1', '1']]).view(np.chararray)
+        assert_array_equal(A1, (A % 1))
+
+        A2 = np.array([['1.000', '2'], ['3', '4']]).view(np.chararray)
+        assert_array_equal(A2, (A % [[1, 2], [3, 4]]))
+
+    def test_rmod(self):
+        assert_(("%s" % self.A) == str(self.A))
+        assert_(("%r" % self.A) == repr(self.A))
+
+        for ob in [42, object()]:
+            with assert_raises_regex(
+                    TypeError, "unsupported operand type.* and 'chararray'"):
+                ob % self.A
+
+    def test_slice(self):
+        """Regression test for https://github.com/numpy/numpy/issues/5982"""
+
+        arr = np.array([['abc ', 'def '], ['geh ', 'ijk ']],
+                       dtype='S4').view(np.chararray)
+        sl1 = arr[:]
+        assert_array_equal(sl1, arr)
+        assert_(sl1.base is arr)
+        assert_(sl1.base.base is arr.base)
+
+        sl2 = arr[:, :]
+        assert_array_equal(sl2, arr)
+        assert_(sl2.base is arr)
+        assert_(sl2.base.base is arr.base)
+
+        assert_(arr[0, 0] == b'abc')
+
+
+def test_empty_indexing():
+    """Regression test for ticket 1948."""
+    # Check that indexing a chararray with an empty list/array returns an
+    # empty chararray instead of a chararray with a single empty string in it.
+    s = np.chararray((4,))
+    assert_(s[[]].size == 0)
+
+
+@pytest.mark.parametrize(["dt1", "dt2"],
+        [("S", "U"), ("U", "S"), ("S", "O"), ("U", "O"),
+         ("S", "d"), ("S", "V")])
+def test_add_types(dt1, dt2):
+    arr1 = np.array([1234234], dtype=dt1)
+    # If the following fails, e.g. use a number and test "V" explicitly
+    arr2 = np.array([b"423"], dtype=dt2)
+    with pytest.raises(TypeError,
+            match=f".*same dtype kind.*{arr1.dtype}.*{arr2.dtype}"):
+        np.char.add(arr1, arr2)

.venv/lib/python3.11/site-packages/numpy/core/tests/test_deprecations.py

@@ -0,0 +1,817 @@
+"""
+Tests related to deprecation warnings. Also a convenient place
+to document how deprecations should eventually be turned into errors.
+
+"""
+import datetime
+import operator
+import warnings
+import pytest
+import tempfile
+import re
+import sys
+
+import numpy as np
+from numpy.testing import (
+    assert_raises, assert_warns, assert_, assert_array_equal, SkipTest,
+    KnownFailureException, break_cycles,
+    )
+
+from numpy.core._multiarray_tests import fromstring_null_term_c_api
+
+try:
+    import pytz
+    _has_pytz = True
+except ImportError:
+    _has_pytz = False
+
+
+class _DeprecationTestCase:
+    # Just as warning: warnings uses re.match, so the start of this message
+    # must match.
+    message = ''
+    warning_cls = DeprecationWarning
+
+    def setup_method(self):
+        self.warn_ctx = warnings.catch_warnings(record=True)
+        self.log = self.warn_ctx.__enter__()
+
+        # Do *not* ignore other DeprecationWarnings. Ignoring warnings
+        # can give very confusing results because of
+        # https://bugs.python.org/issue4180 and it is probably simplest to
+        # try to keep the tests cleanly giving only the right warning type.
+        # (While checking them set to "error" those are ignored anyway)
+        # We still have them show up, because otherwise they would be raised
+        warnings.filterwarnings("always", category=self.warning_cls)
+        warnings.filterwarnings("always", message=self.message,
+                                category=self.warning_cls)
+
+    def teardown_method(self):
+        self.warn_ctx.__exit__()
+
+    def assert_deprecated(self, function, num=1, ignore_others=False,
+                          function_fails=False,
+                          exceptions=np._NoValue,
+                          args=(), kwargs={}):
+        """Test if DeprecationWarnings are given and raised.
+
+        This first checks if the function when called gives `num`
+        DeprecationWarnings, after that it tries to raise these
+        DeprecationWarnings and compares them with `exceptions`.
+        The exceptions can be different for cases where this code path
+        is simply not anticipated and the exception is replaced.
+
+        Parameters
+        ----------
+        function : callable
+            The function to test
+        num : int
+            Number of DeprecationWarnings to expect. This should normally be 1.
+        ignore_others : bool
+            Whether warnings of the wrong type should be ignored (note that
+            the message is not checked)
+        function_fails : bool
+            If the function would normally fail, setting this will check for
+            warnings inside a try/except block.
+        exceptions : Exception or tuple of Exceptions
+            Exception to expect when turning the warnings into an error.
+            The default checks for DeprecationWarnings. If exceptions is
+            empty the function is expected to run successfully.
+        args : tuple
+            Arguments for `function`
+        kwargs : dict
+            Keyword arguments for `function`
+        """
+        __tracebackhide__ = True  # Hide traceback for py.test
+
+        # reset the log
+        self.log[:] = []
+
+        if exceptions is np._NoValue:
+            exceptions = (self.warning_cls,)
+
+        try:
+            function(*args, **kwargs)
+        except (Exception if function_fails else tuple()):
+            pass
+
+        # just in case, clear the registry
+        num_found = 0
+        for warning in self.log:
+            if warning.category is self.warning_cls:
+                num_found += 1
+            elif not ignore_others:
+                raise AssertionError(
+                        "expected %s but got: %s" %
+                        (self.warning_cls.__name__, warning.category))
+        if num is not None and num_found != num:
+            msg = "%i warnings found but %i expected." % (len(self.log), num)
+            lst = [str(w) for w in self.log]
+            raise AssertionError("\n".join([msg] + lst))
+
+        with warnings.catch_warnings():
+            warnings.filterwarnings("error", message=self.message,
+                                    category=self.warning_cls)
+            try:
+                function(*args, **kwargs)
+                if exceptions != tuple():
+                    raise AssertionError(
+                            "No error raised during function call")
+            except exceptions:
+                if exceptions == tuple():
+                    raise AssertionError(
+                            "Error raised during function call")
+
+    def assert_not_deprecated(self, function, args=(), kwargs={}):
+        """Test that warnings are not raised.
+
+        This is just a shorthand for:
+
+        self.assert_deprecated(function, num=0, ignore_others=True,
+                        exceptions=tuple(), args=args, kwargs=kwargs)
+        """
+        self.assert_deprecated(function, num=0, ignore_others=True,
+                        exceptions=tuple(), args=args, kwargs=kwargs)
+
+
+class _VisibleDeprecationTestCase(_DeprecationTestCase):
+    warning_cls = np.VisibleDeprecationWarning
+
+
+class TestDatetime64Timezone(_DeprecationTestCase):
+    """Parsing of datetime64 with timezones deprecated in 1.11.0, because
+    datetime64 is now timezone naive rather than UTC only.
+
+    It will be quite a while before we can remove this, because, at the very
+    least, a lot of existing code uses the 'Z' modifier to avoid conversion
+    from local time to UTC, even if otherwise it handles time in a timezone
+    naive fashion.
+    """
+    def test_string(self):
+        self.assert_deprecated(np.datetime64, args=('2000-01-01T00+01',))
+        self.assert_deprecated(np.datetime64, args=('2000-01-01T00Z',))
+
+    @pytest.mark.skipif(not _has_pytz,
+                        reason="The pytz module is not available.")
+    def test_datetime(self):
+        tz = pytz.timezone('US/Eastern')
+        dt = datetime.datetime(2000, 1, 1, 0, 0, tzinfo=tz)
+        self.assert_deprecated(np.datetime64, args=(dt,))
+
+
+class TestArrayDataAttributeAssignmentDeprecation(_DeprecationTestCase):
+    """Assigning the 'data' attribute of an ndarray is unsafe as pointed
+     out in gh-7093. Eventually, such assignment should NOT be allowed, but
+     in the interests of maintaining backwards compatibility, only a Deprecation-
+     Warning will be raised instead for the time being to give developers time to
+     refactor relevant code.
+    """
+
+    def test_data_attr_assignment(self):
+        a = np.arange(10)
+        b = np.linspace(0, 1, 10)
+
+        self.message = ("Assigning the 'data' attribute is an "
+                        "inherently unsafe operation and will "
+                        "be removed in the future.")
+        self.assert_deprecated(a.__setattr__, args=('data', b.data))
+
+
+class TestBinaryReprInsufficientWidthParameterForRepresentation(_DeprecationTestCase):
+    """
+    If a 'width' parameter is passed into ``binary_repr`` that is insufficient to
+    represent the number in base 2 (positive) or 2's complement (negative) form,
+    the function used to silently ignore the parameter and return a representation
+    using the minimal number of bits needed for the form in question. Such behavior
+    is now considered unsafe from a user perspective and will raise an error in the future.
+    """
+
+    def test_insufficient_width_positive(self):
+        args = (10,)
+        kwargs = {'width': 2}
+
+        self.message = ("Insufficient bit width provided. This behavior "
+                        "will raise an error in the future.")
+        self.assert_deprecated(np.binary_repr, args=args, kwargs=kwargs)
+
+    def test_insufficient_width_negative(self):
+        args = (-5,)
+        kwargs = {'width': 2}
+
+        self.message = ("Insufficient bit width provided. This behavior "
+                        "will raise an error in the future.")
+        self.assert_deprecated(np.binary_repr, args=args, kwargs=kwargs)
+
+
+class TestDTypeAttributeIsDTypeDeprecation(_DeprecationTestCase):
+    # Deprecated 2021-01-05, NumPy 1.21
+    message = r".*`.dtype` attribute"
+
+    def test_deprecation_dtype_attribute_is_dtype(self):
+        class dt:
+            dtype = "f8"
+
+        class vdt(np.void):
+            dtype = "f,f"
+
+        self.assert_deprecated(lambda: np.dtype(dt))
+        self.assert_deprecated(lambda: np.dtype(dt()))
+        self.assert_deprecated(lambda: np.dtype(vdt))
+        self.assert_deprecated(lambda: np.dtype(vdt(1)))
+
+
+class TestTestDeprecated:
+    def test_assert_deprecated(self):
+        test_case_instance = _DeprecationTestCase()
+        test_case_instance.setup_method()
+        assert_raises(AssertionError,
+                      test_case_instance.assert_deprecated,
+                      lambda: None)
+
+        def foo():
+            warnings.warn("foo", category=DeprecationWarning, stacklevel=2)
+
+        test_case_instance.assert_deprecated(foo)
+        test_case_instance.teardown_method()
+
+
+class TestNonNumericConjugate(_DeprecationTestCase):
+    """
+    Deprecate no-op behavior of ndarray.conjugate on non-numeric dtypes,
+    which conflicts with the error behavior of np.conjugate.
+    """
+    def test_conjugate(self):
+        for a in np.array(5), np.array(5j):
+            self.assert_not_deprecated(a.conjugate)
+        for a in (np.array('s'), np.array('2016', 'M'),
+                np.array((1, 2), [('a', int), ('b', int)])):
+            self.assert_deprecated(a.conjugate)
+
+
+class TestNPY_CHAR(_DeprecationTestCase):
+    # 2017-05-03, 1.13.0
+    def test_npy_char_deprecation(self):
+        from numpy.core._multiarray_tests import npy_char_deprecation
+        self.assert_deprecated(npy_char_deprecation)
+        assert_(npy_char_deprecation() == 'S1')
+
+
+class TestPyArray_AS1D(_DeprecationTestCase):
+    def test_npy_pyarrayas1d_deprecation(self):
+        from numpy.core._multiarray_tests import npy_pyarrayas1d_deprecation
+        assert_raises(NotImplementedError, npy_pyarrayas1d_deprecation)
+
+
+class TestPyArray_AS2D(_DeprecationTestCase):
+    def test_npy_pyarrayas2d_deprecation(self):
+        from numpy.core._multiarray_tests import npy_pyarrayas2d_deprecation
+        assert_raises(NotImplementedError, npy_pyarrayas2d_deprecation)
+
+
+class TestDatetimeEvent(_DeprecationTestCase):
+    # 2017-08-11, 1.14.0
+    def test_3_tuple(self):
+        for cls in (np.datetime64, np.timedelta64):
+            # two valid uses - (unit, num) and (unit, num, den, None)
+            self.assert_not_deprecated(cls, args=(1, ('ms', 2)))
+            self.assert_not_deprecated(cls, args=(1, ('ms', 2, 1, None)))
+
+            # trying to use the event argument, removed in 1.7.0, is deprecated
+            # it used to be a uint8
+            self.assert_deprecated(cls, args=(1, ('ms', 2, 'event')))
+            self.assert_deprecated(cls, args=(1, ('ms', 2, 63)))
+            self.assert_deprecated(cls, args=(1, ('ms', 2, 1, 'event')))
+            self.assert_deprecated(cls, args=(1, ('ms', 2, 1, 63)))
+
+
+class TestTruthTestingEmptyArrays(_DeprecationTestCase):
+    # 2017-09-25, 1.14.0
+    message = '.*truth value of an empty array is ambiguous.*'
+
+    def test_1d(self):
+        self.assert_deprecated(bool, args=(np.array([]),))
+
+    def test_2d(self):
+        self.assert_deprecated(bool, args=(np.zeros((1, 0)),))
+        self.assert_deprecated(bool, args=(np.zeros((0, 1)),))
+        self.assert_deprecated(bool, args=(np.zeros((0, 0)),))
+
+
+class TestBincount(_DeprecationTestCase):
+    # 2017-06-01, 1.14.0
+    def test_bincount_minlength(self):
+        self.assert_deprecated(lambda: np.bincount([1, 2, 3], minlength=None))
+
+
+
+class TestGeneratorSum(_DeprecationTestCase):
+    # 2018-02-25, 1.15.0
+    def test_generator_sum(self):
+        self.assert_deprecated(np.sum, args=((i for i in range(5)),))
+
+
+class TestFromstring(_DeprecationTestCase):
+    # 2017-10-19, 1.14
+    def test_fromstring(self):
+        self.assert_deprecated(np.fromstring, args=('\x00'*80,))
+
+
+class TestFromStringAndFileInvalidData(_DeprecationTestCase):
+    # 2019-06-08, 1.17.0
+    # Tests should be moved to real tests when deprecation is done.
+    message = "string or file could not be read to its end"
+
+    @pytest.mark.parametrize("invalid_str", [",invalid_data", "invalid_sep"])
+    def test_deprecate_unparsable_data_file(self, invalid_str):
+        x = np.array([1.51, 2, 3.51, 4], dtype=float)
+
+        with tempfile.TemporaryFile(mode="w") as f:
+            x.tofile(f, sep=',', format='%.2f')
+            f.write(invalid_str)
+
+            f.seek(0)
+            self.assert_deprecated(lambda: np.fromfile(f, sep=","))
+            f.seek(0)
+            self.assert_deprecated(lambda: np.fromfile(f, sep=",", count=5))
+            # Should not raise:
+            with warnings.catch_warnings():
+                warnings.simplefilter("error", DeprecationWarning)
+                f.seek(0)
+                res = np.fromfile(f, sep=",", count=4)
+                assert_array_equal(res, x)
+
+    @pytest.mark.parametrize("invalid_str", [",invalid_data", "invalid_sep"])
+    def test_deprecate_unparsable_string(self, invalid_str):
+        x = np.array([1.51, 2, 3.51, 4], dtype=float)
+        x_str = "1.51,2,3.51,4{}".format(invalid_str)
+
+        self.assert_deprecated(lambda: np.fromstring(x_str, sep=","))
+        self.assert_deprecated(lambda: np.fromstring(x_str, sep=",", count=5))
+
+        # The C-level API can use not fixed size, but 0 terminated strings,
+        # so test that as well:
+        bytestr = x_str.encode("ascii")
+        self.assert_deprecated(lambda: fromstring_null_term_c_api(bytestr))
+
+        with assert_warns(DeprecationWarning):
+            # this is slightly strange, in that fromstring leaves data
+            # potentially uninitialized (would be good to error when all is
+            # read, but count is larger then actual data maybe).
+            res = np.fromstring(x_str, sep=",", count=5)
+            assert_array_equal(res[:-1], x)
+
+        with warnings.catch_warnings():
+            warnings.simplefilter("error", DeprecationWarning)
+
+            # Should not raise:
+            res = np.fromstring(x_str, sep=",", count=4)
+            assert_array_equal(res, x)
+
+
+class Test_GetSet_NumericOps(_DeprecationTestCase):
+    # 2018-09-20, 1.16.0
+    def test_get_numeric_ops(self):
+        from numpy.core._multiarray_tests import getset_numericops
+        self.assert_deprecated(getset_numericops, num=2)
+
+        # empty kwargs prevents any state actually changing which would break
+        # other tests.
+        self.assert_deprecated(np.set_numeric_ops, kwargs={})
+        assert_raises(ValueError, np.set_numeric_ops, add='abc')
+
+
+class TestShape1Fields(_DeprecationTestCase):
+    warning_cls = FutureWarning
+
+    # 2019-05-20, 1.17.0
+    def test_shape_1_fields(self):
+        self.assert_deprecated(np.dtype, args=([('a', int, 1)],))
+
+
+class TestNonZero(_DeprecationTestCase):
+    # 2019-05-26, 1.17.0
+    def test_zerod(self):
+        self.assert_deprecated(lambda: np.nonzero(np.array(0)))
+        self.assert_deprecated(lambda: np.nonzero(np.array(1)))
+
+
+class TestToString(_DeprecationTestCase):
+    # 2020-03-06 1.19.0
+    message = re.escape("tostring() is deprecated. Use tobytes() instead.")
+
+    def test_tostring(self):
+        arr = np.array(list(b"test\xFF"), dtype=np.uint8)
+        self.assert_deprecated(arr.tostring)
+
+    def test_tostring_matches_tobytes(self):
+        arr = np.array(list(b"test\xFF"), dtype=np.uint8)
+        b = arr.tobytes()
+        with assert_warns(DeprecationWarning):
+            s = arr.tostring()
+        assert s == b
+
+
+class TestDTypeCoercion(_DeprecationTestCase):
+    # 2020-02-06 1.19.0
+    message = "Converting .* to a dtype .*is deprecated"
+    deprecated_types = [
+        # The builtin scalar super types:
+        np.generic, np.flexible, np.number,
+        np.inexact, np.floating, np.complexfloating,
+        np.integer, np.unsignedinteger, np.signedinteger,
+        # character is a deprecated S1 special case:
+        np.character,
+    ]
+
+    def test_dtype_coercion(self):
+        for scalar_type in self.deprecated_types:
+            self.assert_deprecated(np.dtype, args=(scalar_type,))
+
+    def test_array_construction(self):
+        for scalar_type in self.deprecated_types:
+            self.assert_deprecated(np.array, args=([], scalar_type,))
+
+    def test_not_deprecated(self):
+        # All specific types are not deprecated:
+        for group in np.sctypes.values():
+            for scalar_type in group:
+                self.assert_not_deprecated(np.dtype, args=(scalar_type,))
+
+        for scalar_type in [type, dict, list, tuple]:
+            # Typical python types are coerced to object currently:
+            self.assert_not_deprecated(np.dtype, args=(scalar_type,))
+
+
+class BuiltInRoundComplexDType(_DeprecationTestCase):
+    # 2020-03-31 1.19.0
+    deprecated_types = [np.csingle, np.cdouble, np.clongdouble]
+    not_deprecated_types = [
+        np.int8, np.int16, np.int32, np.int64,
+        np.uint8, np.uint16, np.uint32, np.uint64,
+        np.float16, np.float32, np.float64,
+    ]
+
+    def test_deprecated(self):
+        for scalar_type in self.deprecated_types:
+            scalar = scalar_type(0)
+            self.assert_deprecated(round, args=(scalar,))
+            self.assert_deprecated(round, args=(scalar, 0))
+            self.assert_deprecated(round, args=(scalar,), kwargs={'ndigits': 0})
+
+    def test_not_deprecated(self):
+        for scalar_type in self.not_deprecated_types:
+            scalar = scalar_type(0)
+            self.assert_not_deprecated(round, args=(scalar,))
+            self.assert_not_deprecated(round, args=(scalar, 0))
+            self.assert_not_deprecated(round, args=(scalar,), kwargs={'ndigits': 0})
+
+
+class TestIncorrectAdvancedIndexWithEmptyResult(_DeprecationTestCase):
+    # 2020-05-27, NumPy 1.20.0
+    message = "Out of bound index found. This was previously ignored.*"
+
+    @pytest.mark.parametrize("index", [([3, 0],), ([0, 0], [3, 0])])
+    def test_empty_subspace(self, index):
+        # Test for both a single and two/multiple advanced indices. These
+        # This will raise an IndexError in the future.
+        arr = np.ones((2, 2, 0))
+        self.assert_deprecated(arr.__getitem__, args=(index,))
+        self.assert_deprecated(arr.__setitem__, args=(index, 0.))
+
+        # for this array, the subspace is only empty after applying the slice
+        arr2 = np.ones((2, 2, 1))
+        index2 = (slice(0, 0),) + index
+        self.assert_deprecated(arr2.__getitem__, args=(index2,))
+        self.assert_deprecated(arr2.__setitem__, args=(index2, 0.))
+
+    def test_empty_index_broadcast_not_deprecated(self):
+        arr = np.ones((2, 2, 2))
+
+        index = ([[3], [2]], [])  # broadcast to an empty result.
+        self.assert_not_deprecated(arr.__getitem__, args=(index,))
+        self.assert_not_deprecated(arr.__setitem__,
+                                   args=(index, np.empty((2, 0, 2))))
+
+
+class TestNonExactMatchDeprecation(_DeprecationTestCase):
+    # 2020-04-22
+    def test_non_exact_match(self):
+        arr = np.array([[3, 6, 6], [4, 5, 1]])
+        # misspelt mode check
+        self.assert_deprecated(lambda: np.ravel_multi_index(arr, (7, 6), mode='Cilp'))
+        # using completely different word with first character as R
+        self.assert_deprecated(lambda: np.searchsorted(arr[0], 4, side='Random'))
+
+
+class TestMatrixInOuter(_DeprecationTestCase):
+    # 2020-05-13 NumPy 1.20.0
+    message = (r"add.outer\(\) was passed a numpy matrix as "
+               r"(first|second) argument.")
+
+    def test_deprecated(self):
+        arr = np.array([1, 2, 3])
+        m = np.array([1, 2, 3]).view(np.matrix)
+        self.assert_deprecated(np.add.outer, args=(m, m), num=2)
+        self.assert_deprecated(np.add.outer, args=(arr, m))
+        self.assert_deprecated(np.add.outer, args=(m, arr))
+        self.assert_not_deprecated(np.add.outer, args=(arr, arr))
+
+
+class FlatteningConcatenateUnsafeCast(_DeprecationTestCase):
+    # NumPy 1.20, 2020-09-03
+    message = "concatenate with `axis=None` will use same-kind casting"
+
+    def test_deprecated(self):
+        self.assert_deprecated(np.concatenate,
+                args=(([0.], [1.]),),
+                kwargs=dict(axis=None, out=np.empty(2, dtype=np.int64)))
+
+    def test_not_deprecated(self):
+        self.assert_not_deprecated(np.concatenate,
+                args=(([0.], [1.]),),
+                kwargs={'axis': None, 'out': np.empty(2, dtype=np.int64),
+                        'casting': "unsafe"})
+
+        with assert_raises(TypeError):
+            # Tests should notice if the deprecation warning is given first...
+            np.concatenate(([0.], [1.]), out=np.empty(2, dtype=np.int64),
+                           casting="same_kind")
+
+
+class TestDeprecatedUnpickleObjectScalar(_DeprecationTestCase):
+    # Deprecated 2020-11-24, NumPy 1.20
+    """
+    Technically, it should be impossible to create numpy object scalars,
+    but there was an unpickle path that would in theory allow it. That
+    path is invalid and must lead to the warning.
+    """
+    message = "Unpickling a scalar with object dtype is deprecated."
+
+    def test_deprecated(self):
+        ctor = np.core.multiarray.scalar
+        self.assert_deprecated(lambda: ctor(np.dtype("O"), 1))
+
+
+class TestSingleElementSignature(_DeprecationTestCase):
+    # Deprecated 2021-04-01, NumPy 1.21
+    message = r"The use of a length 1"
+
+    def test_deprecated(self):
+        self.assert_deprecated(lambda: np.add(1, 2, signature="d"))
+        self.assert_deprecated(lambda: np.add(1, 2, sig=(np.dtype("l"),)))
+
+
+class TestCtypesGetter(_DeprecationTestCase):
+    # Deprecated 2021-05-18, Numpy 1.21.0
+    warning_cls = DeprecationWarning
+    ctypes = np.array([1]).ctypes
+
+    @pytest.mark.parametrize(
+        "name", ["get_data", "get_shape", "get_strides", "get_as_parameter"]
+    )
+    def test_deprecated(self, name: str) -> None:
+        func = getattr(self.ctypes, name)
+        self.assert_deprecated(lambda: func())
+
+    @pytest.mark.parametrize(
+        "name", ["data", "shape", "strides", "_as_parameter_"]
+    )
+    def test_not_deprecated(self, name: str) -> None:
+        self.assert_not_deprecated(lambda: getattr(self.ctypes, name))
+
+
+PARTITION_DICT = {
+    "partition method": np.arange(10).partition,
+    "argpartition method": np.arange(10).argpartition,
+    "partition function": lambda kth: np.partition(np.arange(10), kth),
+    "argpartition function": lambda kth: np.argpartition(np.arange(10), kth),
+}
+
+
+@pytest.mark.parametrize("func", PARTITION_DICT.values(), ids=PARTITION_DICT)
+class TestPartitionBoolIndex(_DeprecationTestCase):
+    # Deprecated 2021-09-29, NumPy 1.22
+    warning_cls = DeprecationWarning
+    message = "Passing booleans as partition index is deprecated"
+
+    def test_deprecated(self, func):
+        self.assert_deprecated(lambda: func(True))
+        self.assert_deprecated(lambda: func([False, True]))
+
+    def test_not_deprecated(self, func):
+        self.assert_not_deprecated(lambda: func(1))
+        self.assert_not_deprecated(lambda: func([0, 1]))
+
+
+class TestMachAr(_DeprecationTestCase):
+    # Deprecated 2022-11-22, NumPy 1.25
+    warning_cls = DeprecationWarning
+
+    def test_deprecated_module(self):
+        self.assert_deprecated(lambda: getattr(np.core, "MachAr"))
+
+
+class TestQuantileInterpolationDeprecation(_DeprecationTestCase):
+    # Deprecated 2021-11-08, NumPy 1.22
+    @pytest.mark.parametrize("func",
+        [np.percentile, np.quantile, np.nanpercentile, np.nanquantile])
+    def test_deprecated(self, func):
+        self.assert_deprecated(
+            lambda: func([0., 1.], 0., interpolation="linear"))
+        self.assert_deprecated(
+            lambda: func([0., 1.], 0., interpolation="nearest"))
+
+    @pytest.mark.parametrize("func",
+            [np.percentile, np.quantile, np.nanpercentile, np.nanquantile])
+    def test_both_passed(self, func):
+        with warnings.catch_warnings():
+            # catch the DeprecationWarning so that it does not raise:
+            warnings.simplefilter("always", DeprecationWarning)
+            with pytest.raises(TypeError):
+                func([0., 1.], 0., interpolation="nearest", method="nearest")
+
+
+class TestMemEventHook(_DeprecationTestCase):
+    # Deprecated 2021-11-18, NumPy 1.23
+    def test_mem_seteventhook(self):
+        # The actual tests are within the C code in
+        # multiarray/_multiarray_tests.c.src
+        import numpy.core._multiarray_tests as ma_tests
+        with pytest.warns(DeprecationWarning,
+                          match='PyDataMem_SetEventHook is deprecated'):
+            ma_tests.test_pydatamem_seteventhook_start()
+        # force an allocation and free of a numpy array
+        # needs to be larger then limit of small memory cacher in ctors.c
+        a = np.zeros(1000)
+        del a
+        break_cycles()
+        with pytest.warns(DeprecationWarning,
+                          match='PyDataMem_SetEventHook is deprecated'):
+            ma_tests.test_pydatamem_seteventhook_end()
+
+
+class TestArrayFinalizeNone(_DeprecationTestCase):
+    message = "Setting __array_finalize__ = None"
+
+    def test_use_none_is_deprecated(self):
+        # Deprecated way that ndarray itself showed nothing needs finalizing.
+        class NoFinalize(np.ndarray):
+            __array_finalize__ = None
+
+        self.assert_deprecated(lambda: np.array(1).view(NoFinalize))
+
+class TestAxisNotMAXDIMS(_DeprecationTestCase):
+    # Deprecated 2022-01-08, NumPy 1.23
+    message = r"Using `axis=32` \(MAXDIMS\) is deprecated"
+
+    def test_deprecated(self):
+        a = np.zeros((1,)*32)
+        self.assert_deprecated(lambda: np.repeat(a, 1, axis=np.MAXDIMS))
+
+
+class TestLoadtxtParseIntsViaFloat(_DeprecationTestCase):
+    # Deprecated 2022-07-03, NumPy 1.23
+    # This test can be removed without replacement after the deprecation.
+    # The tests:
+    #   * numpy/lib/tests/test_loadtxt.py::test_integer_signs
+    #   * lib/tests/test_loadtxt.py::test_implicit_cast_float_to_int_fails
+    # Have a warning filter that needs to be removed.
+    message = r"loadtxt\(\): Parsing an integer via a float is deprecated.*"
+
+    @pytest.mark.parametrize("dtype", np.typecodes["AllInteger"])
+    def test_deprecated_warning(self, dtype):
+        with pytest.warns(DeprecationWarning, match=self.message):
+            np.loadtxt(["10.5"], dtype=dtype)
+
+    @pytest.mark.parametrize("dtype", np.typecodes["AllInteger"])
+    def test_deprecated_raised(self, dtype):
+        # The DeprecationWarning is chained when raised, so test manually:
+        with warnings.catch_warnings():
+            warnings.simplefilter("error", DeprecationWarning)
+            try:
+                np.loadtxt(["10.5"], dtype=dtype)
+            except ValueError as e:
+                assert isinstance(e.__cause__, DeprecationWarning)
+
+
+class TestScalarConversion(_DeprecationTestCase):
+    # 2023-01-02, 1.25.0
+    def test_float_conversion(self):
+        self.assert_deprecated(float, args=(np.array([3.14]),))
+
+    def test_behaviour(self):
+        b = np.array([[3.14]])
+        c = np.zeros(5)
+        with pytest.warns(DeprecationWarning):
+            c[0] = b
+
+
+class TestPyIntConversion(_DeprecationTestCase):
+    message = r".*stop allowing conversion of out-of-bound.*"
+
+    @pytest.mark.parametrize("dtype", np.typecodes["AllInteger"])
+    def test_deprecated_scalar(self, dtype):
+        dtype = np.dtype(dtype)
+        info = np.iinfo(dtype)
+
+        # Cover the most common creation paths (all end up in the
+        # same place):
+        def scalar(value, dtype):
+            dtype.type(value)
+
+        def assign(value, dtype):
+            arr = np.array([0, 0, 0], dtype=dtype)
+            arr[2] = value
+
+        def create(value, dtype):
+            np.array([value], dtype=dtype)
+
+        for creation_func in [scalar, assign, create]:
+            try:
+                self.assert_deprecated(
+                        lambda: creation_func(info.min - 1, dtype))
+            except OverflowError:
+                pass  # OverflowErrors always happened also before and are OK.
+
+            try:
+                self.assert_deprecated(
+                        lambda: creation_func(info.max + 1, dtype))
+            except OverflowError:
+                pass  # OverflowErrors always happened also before and are OK.
+
+
+class TestDeprecatedGlobals(_DeprecationTestCase):
+    # Deprecated 2022-11-17, NumPy 1.24
+    def test_type_aliases(self):
+        # from builtins
+        self.assert_deprecated(lambda: np.bool8)
+        self.assert_deprecated(lambda: np.int0)
+        self.assert_deprecated(lambda: np.uint0)
+        self.assert_deprecated(lambda: np.bytes0)
+        self.assert_deprecated(lambda: np.str0)
+        self.assert_deprecated(lambda: np.object0)
+
+
+@pytest.mark.parametrize("name",
+        ["bool", "long", "ulong", "str", "bytes", "object"])
+def test_future_scalar_attributes(name):
+    # FutureWarning added 2022-11-17, NumPy 1.24,
+    assert name not in dir(np)  # we may want to not add them
+    with pytest.warns(FutureWarning,
+            match=f"In the future .*{name}"):
+        assert not hasattr(np, name)
+
+    # Unfortunately, they are currently still valid via `np.dtype()`
+    np.dtype(name)
+    name in np.sctypeDict
+
+
+# Ignore the above future attribute warning for this test.
+@pytest.mark.filterwarnings("ignore:In the future:FutureWarning")
+class TestRemovedGlobals:
+    # Removed 2023-01-12, NumPy 1.24.0
+    # Not a deprecation, but the large error was added to aid those who missed
+    # the previous deprecation, and should be removed similarly to one
+    # (or faster).
+    @pytest.mark.parametrize("name",
+            ["object", "bool", "float", "complex", "str", "int"])
+    def test_attributeerror_includes_info(self, name):
+        msg = f".*\n`np.{name}` was a deprecated alias for the builtin"
+        with pytest.raises(AttributeError, match=msg):
+            getattr(np, name)
+
+
+class TestDeprecatedFinfo(_DeprecationTestCase):
+    # Deprecated in NumPy 1.25, 2023-01-16
+    def test_deprecated_none(self):
+        self.assert_deprecated(np.finfo, args=(None,))
+
+class TestFromnumeric(_DeprecationTestCase):
+    # 2023-02-28, 1.25.0
+    def test_round_(self):
+        self.assert_deprecated(lambda: np.round_(np.array([1.5, 2.5, 3.5])))
+
+    # 2023-03-02, 1.25.0
+    def test_cumproduct(self):
+        self.assert_deprecated(lambda: np.cumproduct(np.array([1, 2, 3])))
+
+    # 2023-03-02, 1.25.0
+    def test_product(self):
+        self.assert_deprecated(lambda: np.product(np.array([1, 2, 3])))
+
+    # 2023-03-02, 1.25.0
+    def test_sometrue(self):
+        self.assert_deprecated(lambda: np.sometrue(np.array([True, False])))
+
+    # 2023-03-02, 1.25.0
+    def test_alltrue(self):
+        self.assert_deprecated(lambda: np.alltrue(np.array([True, False])))
+
+
+class TestMathAlias(_DeprecationTestCase):
+    # Deprecated in Numpy 1.25, 2023-04-06
+    def test_deprecated_np_math(self):
+        self.assert_deprecated(lambda: np.math)
+
+    def test_deprecated_np_lib_math(self):
+        self.assert_deprecated(lambda: np.lib.math)

.venv/lib/python3.11/site-packages/numpy/core/tests/test_dlpack.py

@@ -0,0 +1,124 @@
+import sys
+import pytest
+
+import numpy as np
+from numpy.testing import assert_array_equal, IS_PYPY
+
+
+class TestDLPack:
+    @pytest.mark.skipif(IS_PYPY, reason="PyPy can't get refcounts.")
+    def test_dunder_dlpack_refcount(self):
+        x = np.arange(5)
+        y = x.__dlpack__()
+        assert sys.getrefcount(x) == 3
+        del y
+        assert sys.getrefcount(x) == 2
+
+    def test_dunder_dlpack_stream(self):
+        x = np.arange(5)
+        x.__dlpack__(stream=None)
+
+        with pytest.raises(RuntimeError):
+            x.__dlpack__(stream=1)
+
+    def test_strides_not_multiple_of_itemsize(self):
+        dt = np.dtype([('int', np.int32), ('char', np.int8)])
+        y = np.zeros((5,), dtype=dt)
+        z = y['int']
+
+        with pytest.raises(BufferError):
+            np.from_dlpack(z)
+
+    @pytest.mark.skipif(IS_PYPY, reason="PyPy can't get refcounts.")
+    def test_from_dlpack_refcount(self):
+        x = np.arange(5)
+        y = np.from_dlpack(x)
+        assert sys.getrefcount(x) == 3
+        del y
+        assert sys.getrefcount(x) == 2
+
+    @pytest.mark.parametrize("dtype", [
+        np.bool_,
+        np.int8, np.int16, np.int32, np.int64,
+        np.uint8, np.uint16, np.uint32, np.uint64,
+        np.float16, np.float32, np.float64,
+        np.complex64, np.complex128
+    ])
+    def test_dtype_passthrough(self, dtype):
+        x = np.arange(5).astype(dtype)
+        y = np.from_dlpack(x)
+
+        assert y.dtype == x.dtype
+        assert_array_equal(x, y)
+
+    def test_invalid_dtype(self):
+        x = np.asarray(np.datetime64('2021-05-27'))
+
+        with pytest.raises(BufferError):
+            np.from_dlpack(x)
+
+    def test_invalid_byte_swapping(self):
+        dt = np.dtype('=i8').newbyteorder()
+        x = np.arange(5, dtype=dt)
+
+        with pytest.raises(BufferError):
+            np.from_dlpack(x)
+
+    def test_non_contiguous(self):
+        x = np.arange(25).reshape((5, 5))
+
+        y1 = x[0]
+        assert_array_equal(y1, np.from_dlpack(y1))
+
+        y2 = x[:, 0]
+        assert_array_equal(y2, np.from_dlpack(y2))
+
+        y3 = x[1, :]
+        assert_array_equal(y3, np.from_dlpack(y3))
+
+        y4 = x[1]
+        assert_array_equal(y4, np.from_dlpack(y4))
+
+        y5 = np.diagonal(x).copy()
+        assert_array_equal(y5, np.from_dlpack(y5))
+
+    @pytest.mark.parametrize("ndim", range(33))
+    def test_higher_dims(self, ndim):
+        shape = (1,) * ndim
+        x = np.zeros(shape, dtype=np.float64)
+
+        assert shape == np.from_dlpack(x).shape
+
+    def test_dlpack_device(self):
+        x = np.arange(5)
+        assert x.__dlpack_device__() == (1, 0)
+        y = np.from_dlpack(x)
+        assert y.__dlpack_device__() == (1, 0)
+        z = y[::2]
+        assert z.__dlpack_device__() == (1, 0)
+
+    def dlpack_deleter_exception(self):
+        x = np.arange(5)
+        _ = x.__dlpack__()
+        raise RuntimeError
+
+    def test_dlpack_destructor_exception(self):
+        with pytest.raises(RuntimeError):
+            self.dlpack_deleter_exception()
+
+    def test_readonly(self):
+        x = np.arange(5)
+        x.flags.writeable = False
+        with pytest.raises(BufferError):
+            x.__dlpack__()
+
+    def test_ndim0(self):
+        x = np.array(1.0)
+        y = np.from_dlpack(x)
+        assert_array_equal(x, y)
+
+    def test_size1dims_arrays(self):
+        x = np.ndarray(dtype='f8', shape=(10, 5, 1), strides=(8, 80, 4),
+                       buffer=np.ones(1000, dtype=np.uint8), order='F')
+        y = np.from_dlpack(x)
+        assert_array_equal(x, y)

.venv/lib/python3.11/site-packages/numpy/core/tests/test_dtype.py

@@ -0,0 +1,1906 @@
+import sys
+import operator
+import pytest
+import ctypes
+import gc
+import types
+from typing import Any
+
+import numpy as np
+import numpy.dtypes
+from numpy.core._rational_tests import rational
+from numpy.core._multiarray_tests import create_custom_field_dtype
+from numpy.testing import (
+    assert_, assert_equal, assert_array_equal, assert_raises, HAS_REFCOUNT,
+    IS_PYSTON, _OLD_PROMOTION)
+from numpy.compat import pickle
+from itertools import permutations
+import random
+
+import hypothesis
+from hypothesis.extra import numpy as hynp
+
+
+
+def assert_dtype_equal(a, b):
+    assert_equal(a, b)
+    assert_equal(hash(a), hash(b),
+                 "two equivalent types do not hash to the same value !")
+
+def assert_dtype_not_equal(a, b):
+    assert_(a != b)
+    assert_(hash(a) != hash(b),
+            "two different types hash to the same value !")
+
+class TestBuiltin:
+    @pytest.mark.parametrize('t', [int, float, complex, np.int32, str, object,
+                                   np.compat.unicode])
+    def test_run(self, t):
+        """Only test hash runs at all."""
+        dt = np.dtype(t)
+        hash(dt)
+
+    @pytest.mark.parametrize('t', [int, float])
+    def test_dtype(self, t):
+        # Make sure equivalent byte order char hash the same (e.g. < and = on
+        # little endian)
+        dt = np.dtype(t)
+        dt2 = dt.newbyteorder("<")
+        dt3 = dt.newbyteorder(">")
+        if dt == dt2:
+            assert_(dt.byteorder != dt2.byteorder, "bogus test")
+            assert_dtype_equal(dt, dt2)
+        else:
+            assert_(dt.byteorder != dt3.byteorder, "bogus test")
+            assert_dtype_equal(dt, dt3)
+
+    def test_equivalent_dtype_hashing(self):
+        # Make sure equivalent dtypes with different type num hash equal
+        uintp = np.dtype(np.uintp)
+        if uintp.itemsize == 4:
+            left = uintp
+            right = np.dtype(np.uint32)
+        else:
+            left = uintp
+            right = np.dtype(np.ulonglong)
+        assert_(left == right)
+        assert_(hash(left) == hash(right))
+
+    def test_invalid_types(self):
+        # Make sure invalid type strings raise an error
+
+        assert_raises(TypeError, np.dtype, 'O3')
+        assert_raises(TypeError, np.dtype, 'O5')
+        assert_raises(TypeError, np.dtype, 'O7')
+        assert_raises(TypeError, np.dtype, 'b3')
+        assert_raises(TypeError, np.dtype, 'h4')
+        assert_raises(TypeError, np.dtype, 'I5')
+        assert_raises(TypeError, np.dtype, 'e3')
+        assert_raises(TypeError, np.dtype, 'f5')
+
+        if np.dtype('g').itemsize == 8 or np.dtype('g').itemsize == 16:
+            assert_raises(TypeError, np.dtype, 'g12')
+        elif np.dtype('g').itemsize == 12:
+            assert_raises(TypeError, np.dtype, 'g16')
+
+        if np.dtype('l').itemsize == 8:
+            assert_raises(TypeError, np.dtype, 'l4')
+            assert_raises(TypeError, np.dtype, 'L4')
+        else:
+            assert_raises(TypeError, np.dtype, 'l8')
+            assert_raises(TypeError, np.dtype, 'L8')
+
+        if np.dtype('q').itemsize == 8:
+            assert_raises(TypeError, np.dtype, 'q4')
+            assert_raises(TypeError, np.dtype, 'Q4')
+        else:
+            assert_raises(TypeError, np.dtype, 'q8')
+            assert_raises(TypeError, np.dtype, 'Q8')
+
+    def test_richcompare_invalid_dtype_equality(self):
+        # Make sure objects that cannot be converted to valid
+        # dtypes results in False/True when compared to valid dtypes.
+        # Here 7 cannot be converted to dtype. No exceptions should be raised
+
+        assert not np.dtype(np.int32) == 7, "dtype richcompare failed for =="
+        assert np.dtype(np.int32) != 7, "dtype richcompare failed for !="
+
+    @pytest.mark.parametrize(
+        'operation',
+        [operator.le, operator.lt, operator.ge, operator.gt])
+    def test_richcompare_invalid_dtype_comparison(self, operation):
+        # Make sure TypeError is raised for comparison operators
+        # for invalid dtypes. Here 7 is an invalid dtype.
+
+        with pytest.raises(TypeError):
+            operation(np.dtype(np.int32), 7)
+
+    @pytest.mark.parametrize("dtype",
+             ['Bool', 'Bytes0', 'Complex32', 'Complex64',
+              'Datetime64', 'Float16', 'Float32', 'Float64',
+              'Int8', 'Int16', 'Int32', 'Int64',
+              'Object0', 'Str0', 'Timedelta64',
+              'UInt8', 'UInt16', 'Uint32', 'UInt32',
+              'Uint64', 'UInt64', 'Void0',
+              "Float128", "Complex128"])
+    def test_numeric_style_types_are_invalid(self, dtype):
+        with assert_raises(TypeError):
+            np.dtype(dtype)
+
+    def test_remaining_dtypes_with_bad_bytesize(self):
+        # The np.<name> aliases were deprecated, these probably should be too 
+        assert np.dtype("int0") is np.dtype("intp")
+        assert np.dtype("uint0") is np.dtype("uintp")
+        assert np.dtype("bool8") is np.dtype("bool")
+        assert np.dtype("bytes0") is np.dtype("bytes")
+        assert np.dtype("str0") is np.dtype("str")
+        assert np.dtype("object0") is np.dtype("object")
+
+    @pytest.mark.parametrize(
+        'value',
+        ['m8', 'M8', 'datetime64', 'timedelta64',
+         'i4, (2,3)f8, f4', 'a3, 3u8, (3,4)a10',
+         '>f', '<f', '=f', '|f',
+        ])
+    def test_dtype_bytes_str_equivalence(self, value):
+        bytes_value = value.encode('ascii')
+        from_bytes = np.dtype(bytes_value)
+        from_str = np.dtype(value)
+        assert_dtype_equal(from_bytes, from_str)
+
+    def test_dtype_from_bytes(self):
+        # Empty bytes object
+        assert_raises(TypeError, np.dtype, b'')
+        # Byte order indicator, but no type
+        assert_raises(TypeError, np.dtype, b'|')
+
+        # Single character with ordinal < NPY_NTYPES returns
+        # type by index into _builtin_descrs
+        assert_dtype_equal(np.dtype(bytes([0])), np.dtype('bool'))
+        assert_dtype_equal(np.dtype(bytes([17])), np.dtype(object))
+
+        # Single character where value is a valid type code
+        assert_dtype_equal(np.dtype(b'f'), np.dtype('float32'))
+
+        # Bytes with non-ascii values raise errors
+        assert_raises(TypeError, np.dtype, b'\xff')
+        assert_raises(TypeError, np.dtype, b's\xff')
+
+    def test_bad_param(self):
+        # Can't give a size that's too small
+        assert_raises(ValueError, np.dtype,
+                        {'names':['f0', 'f1'],
+                         'formats':['i4', 'i1'],
+                         'offsets':[0, 4],
+                         'itemsize':4})
+        # If alignment is enabled, the alignment (4) must divide the itemsize
+        assert_raises(ValueError, np.dtype,
+                        {'names':['f0', 'f1'],
+                         'formats':['i4', 'i1'],
+                         'offsets':[0, 4],
+                         'itemsize':9}, align=True)
+        # If alignment is enabled, the individual fields must be aligned
+        assert_raises(ValueError, np.dtype,
+                        {'names':['f0', 'f1'],
+                         'formats':['i1', 'f4'],
+                         'offsets':[0, 2]}, align=True)
+
+    def test_field_order_equality(self):
+        x = np.dtype({'names': ['A', 'B'],
+                      'formats': ['i4', 'f4'],
+                      'offsets': [0, 4]})
+        y = np.dtype({'names': ['B', 'A'],
+                      'formats': ['i4', 'f4'],
+                      'offsets': [4, 0]})
+        assert_equal(x == y, False)
+        # This is an safe cast (not equiv) due to the different names:
+        assert np.can_cast(x, y, casting="safe")
+
+    @pytest.mark.parametrize(
+        ["type_char", "char_size", "scalar_type"],
+        [["U", 4, np.str_],
+         ["S", 1, np.bytes_]])
+    def test_create_string_dtypes_directly(
+            self, type_char, char_size, scalar_type):
+        dtype_class = type(np.dtype(type_char))
+
+        dtype = dtype_class(8)
+        assert dtype.type is scalar_type
+        assert dtype.itemsize == 8*char_size
+
+    def test_create_invalid_string_errors(self):
+        one_too_big = np.iinfo(np.intc).max + 1
+        with pytest.raises(TypeError):
+            type(np.dtype("U"))(one_too_big // 4)
+
+        with pytest.raises(TypeError):
+            # Code coverage for very large numbers:
+            type(np.dtype("U"))(np.iinfo(np.intp).max // 4 + 1)
+
+        if one_too_big < sys.maxsize:
+            with pytest.raises(TypeError):
+                type(np.dtype("S"))(one_too_big)
+
+        with pytest.raises(ValueError):
+            type(np.dtype("U"))(-1)
+
+
+class TestRecord:
+    def test_equivalent_record(self):
+        """Test whether equivalent record dtypes hash the same."""
+        a = np.dtype([('yo', int)])
+        b = np.dtype([('yo', int)])
+        assert_dtype_equal(a, b)
+
+    def test_different_names(self):
+        # In theory, they may hash the same (collision) ?
+        a = np.dtype([('yo', int)])
+        b = np.dtype([('ye', int)])
+        assert_dtype_not_equal(a, b)
+
+    def test_different_titles(self):
+        # In theory, they may hash the same (collision) ?
+        a = np.dtype({'names': ['r', 'b'],
+                      'formats': ['u1', 'u1'],
+                      'titles': ['Red pixel', 'Blue pixel']})
+        b = np.dtype({'names': ['r', 'b'],
+                      'formats': ['u1', 'u1'],
+                      'titles': ['RRed pixel', 'Blue pixel']})
+        assert_dtype_not_equal(a, b)
+
+    @pytest.mark.skipif(not HAS_REFCOUNT, reason="Python lacks refcounts")
+    def test_refcount_dictionary_setting(self):
+        names = ["name1"]
+        formats = ["f8"]
+        titles = ["t1"]
+        offsets = [0]
+        d = dict(names=names, formats=formats, titles=titles, offsets=offsets)
+        refcounts = {k: sys.getrefcount(i) for k, i in d.items()}
+        np.dtype(d)
+        refcounts_new = {k: sys.getrefcount(i) for k, i in d.items()}
+        assert refcounts == refcounts_new
+
+    def test_mutate(self):
+        # Mutating a dtype should reset the cached hash value.
+        # NOTE: Mutating should be deprecated, but new API added to replace it.
+        a = np.dtype([('yo', int)])
+        b = np.dtype([('yo', int)])
+        c = np.dtype([('ye', int)])
+        assert_dtype_equal(a, b)
+        assert_dtype_not_equal(a, c)
+        a.names = ['ye']
+        assert_dtype_equal(a, c)
+        assert_dtype_not_equal(a, b)
+        state = b.__reduce__()[2]
+        a.__setstate__(state)
+        assert_dtype_equal(a, b)
+        assert_dtype_not_equal(a, c)
+
+    def test_mutate_error(self):
+        # NOTE: Mutating should be deprecated, but new API added to replace it.
+        a = np.dtype("i,i")
+
+        with pytest.raises(ValueError, match="must replace all names at once"):
+            a.names = ["f0"]
+
+        with pytest.raises(ValueError, match=".*and not string"):
+            a.names = ["f0", b"not a unicode name"]
+
+    def test_not_lists(self):
+        """Test if an appropriate exception is raised when passing bad values to
+        the dtype constructor.
+        """
+        assert_raises(TypeError, np.dtype,
+                      dict(names={'A', 'B'}, formats=['f8', 'i4']))
+        assert_raises(TypeError, np.dtype,
+                      dict(names=['A', 'B'], formats={'f8', 'i4'}))
+
+    def test_aligned_size(self):
+        # Check that structured dtypes get padded to an aligned size
+        dt = np.dtype('i4, i1', align=True)
+        assert_equal(dt.itemsize, 8)
+        dt = np.dtype([('f0', 'i4'), ('f1', 'i1')], align=True)
+        assert_equal(dt.itemsize, 8)
+        dt = np.dtype({'names':['f0', 'f1'],
+                       'formats':['i4', 'u1'],
+                       'offsets':[0, 4]}, align=True)
+        assert_equal(dt.itemsize, 8)
+        dt = np.dtype({'f0': ('i4', 0), 'f1':('u1', 4)}, align=True)
+        assert_equal(dt.itemsize, 8)
+        # Nesting should preserve that alignment
+        dt1 = np.dtype([('f0', 'i4'),
+                       ('f1', [('f1', 'i1'), ('f2', 'i4'), ('f3', 'i1')]),
+                       ('f2', 'i1')], align=True)
+        assert_equal(dt1.itemsize, 20)
+        dt2 = np.dtype({'names':['f0', 'f1', 'f2'],
+                       'formats':['i4',
+                                  [('f1', 'i1'), ('f2', 'i4'), ('f3', 'i1')],
+                                  'i1'],
+                       'offsets':[0, 4, 16]}, align=True)
+        assert_equal(dt2.itemsize, 20)
+        dt3 = np.dtype({'f0': ('i4', 0),
+                       'f1': ([('f1', 'i1'), ('f2', 'i4'), ('f3', 'i1')], 4),
+                       'f2': ('i1', 16)}, align=True)
+        assert_equal(dt3.itemsize, 20)
+        assert_equal(dt1, dt2)
+        assert_equal(dt2, dt3)
+        # Nesting should preserve packing
+        dt1 = np.dtype([('f0', 'i4'),
+                       ('f1', [('f1', 'i1'), ('f2', 'i4'), ('f3', 'i1')]),
+                       ('f2', 'i1')], align=False)
+        assert_equal(dt1.itemsize, 11)
+        dt2 = np.dtype({'names':['f0', 'f1', 'f2'],
+                       'formats':['i4',
+                                  [('f1', 'i1'), ('f2', 'i4'), ('f3', 'i1')],
+                                  'i1'],
+                       'offsets':[0, 4, 10]}, align=False)
+        assert_equal(dt2.itemsize, 11)
+        dt3 = np.dtype({'f0': ('i4', 0),
+                       'f1': ([('f1', 'i1'), ('f2', 'i4'), ('f3', 'i1')], 4),
+                       'f2': ('i1', 10)}, align=False)
+        assert_equal(dt3.itemsize, 11)
+        assert_equal(dt1, dt2)
+        assert_equal(dt2, dt3)
+        # Array of subtype should preserve alignment
+        dt1 = np.dtype([('a', '|i1'),
+                        ('b', [('f0', '<i2'),
+                        ('f1', '<f4')], 2)], align=True)
+        assert_equal(dt1.descr, [('a', '|i1'), ('', '|V3'),
+                                 ('b', [('f0', '<i2'), ('', '|V2'),
+                                 ('f1', '<f4')], (2,))])
+
+    def test_union_struct(self):
+        # Should be able to create union dtypes
+        dt = np.dtype({'names':['f0', 'f1', 'f2'], 'formats':['<u4', '<u2', '<u2'],
+                        'offsets':[0, 0, 2]}, align=True)
+        assert_equal(dt.itemsize, 4)
+        a = np.array([3], dtype='<u4').view(dt)
+        a['f1'] = 10
+        a['f2'] = 36
+        assert_equal(a['f0'], 10 + 36*256*256)
+        # Should be able to specify fields out of order
+        dt = np.dtype({'names':['f0', 'f1', 'f2'], 'formats':['<u4', '<u2', '<u2'],
+                        'offsets':[4, 0, 2]}, align=True)
+        assert_equal(dt.itemsize, 8)
+        # field name should not matter: assignment is by position
+        dt2 = np.dtype({'names':['f2', 'f0', 'f1'],
+                        'formats':['<u4', '<u2', '<u2'],
+                        'offsets':[4, 0, 2]}, align=True)
+        vals = [(0, 1, 2), (3, 2**15-1, 4)]
+        vals2 = [(0, 1, 2), (3, 2**15-1, 4)]
+        a = np.array(vals, dt)
+        b = np.array(vals2, dt2)
+        assert_equal(a.astype(dt2), b)
+        assert_equal(b.astype(dt), a)
+        assert_equal(a.view(dt2), b)
+        assert_equal(b.view(dt), a)
+        # Should not be able to overlap objects with other types
+        assert_raises(TypeError, np.dtype,
+                {'names':['f0', 'f1'],
+                 'formats':['O', 'i1'],
+                 'offsets':[0, 2]})
+        assert_raises(TypeError, np.dtype,
+                {'names':['f0', 'f1'],
+                 'formats':['i4', 'O'],
+                 'offsets':[0, 3]})
+        assert_raises(TypeError, np.dtype,
+                {'names':['f0', 'f1'],
+                 'formats':[[('a', 'O')], 'i1'],
+                 'offsets':[0, 2]})
+        assert_raises(TypeError, np.dtype,
+                {'names':['f0', 'f1'],
+                 'formats':['i4', [('a', 'O')]],
+                 'offsets':[0, 3]})
+        # Out of order should still be ok, however
+        dt = np.dtype({'names':['f0', 'f1'],
+                       'formats':['i1', 'O'],
+                       'offsets':[np.dtype('intp').itemsize, 0]})
+
+    @pytest.mark.parametrize(["obj", "dtype", "expected"],
+        [([], ("(2)f4,"), np.empty((0, 2), dtype="f4")),
+         (3, "(3)f4,", [3, 3, 3]),
+         (np.float64(2), "(2)f4,", [2, 2]),
+         ([((0, 1), (1, 2)), ((2,),)], '(2,2)f4', None),
+         (["1", "2"], "(2)i,", None)])
+    def test_subarray_list(self, obj, dtype, expected):
+        dtype = np.dtype(dtype)
+        res = np.array(obj, dtype=dtype)
+
+        if expected is None:
+            # iterate the 1-d list to fill the array
+            expected = np.empty(len(obj), dtype=dtype)
+            for i in range(len(expected)):
+                expected[i] = obj[i]
+
+        assert_array_equal(res, expected)
+
+    def test_comma_datetime(self):
+        dt = np.dtype('M8[D],datetime64[Y],i8')
+        assert_equal(dt, np.dtype([('f0', 'M8[D]'),
+                                   ('f1', 'datetime64[Y]'),
+                                   ('f2', 'i8')]))
+
+    def test_from_dictproxy(self):
+        # Tests for PR #5920
+        dt = np.dtype({'names': ['a', 'b'], 'formats': ['i4', 'f4']})
+        assert_dtype_equal(dt, np.dtype(dt.fields))
+        dt2 = np.dtype((np.void, dt.fields))
+        assert_equal(dt2.fields, dt.fields)
+
+    def test_from_dict_with_zero_width_field(self):
+        # Regression test for #6430 / #2196
+        dt = np.dtype([('val1', np.float32, (0,)), ('val2', int)])
+        dt2 = np.dtype({'names': ['val1', 'val2'],
+                        'formats': [(np.float32, (0,)), int]})
+
+        assert_dtype_equal(dt, dt2)
+        assert_equal(dt.fields['val1'][0].itemsize, 0)
+        assert_equal(dt.itemsize, dt.fields['val2'][0].itemsize)
+
+    def test_bool_commastring(self):
+        d = np.dtype('?,?,?')  # raises?
+        assert_equal(len(d.names), 3)
+        for n in d.names:
+            assert_equal(d.fields[n][0], np.dtype('?'))
+
+    def test_nonint_offsets(self):
+        # gh-8059
+        def make_dtype(off):
+            return np.dtype({'names': ['A'], 'formats': ['i4'],
+                             'offsets': [off]})
+
+        assert_raises(TypeError, make_dtype, 'ASD')
+        assert_raises(OverflowError, make_dtype, 2**70)
+        assert_raises(TypeError, make_dtype, 2.3)
+        assert_raises(ValueError, make_dtype, -10)
+
+        # no errors here:
+        dt = make_dtype(np.uint32(0))
+        np.zeros(1, dtype=dt)[0].item()
+
+    def test_fields_by_index(self):
+        dt = np.dtype([('a', np.int8), ('b', np.float32, 3)])
+        assert_dtype_equal(dt[0], np.dtype(np.int8))
+        assert_dtype_equal(dt[1], np.dtype((np.float32, 3)))
+        assert_dtype_equal(dt[-1], dt[1])
+        assert_dtype_equal(dt[-2], dt[0])
+        assert_raises(IndexError, lambda: dt[-3])
+
+        assert_raises(TypeError, operator.getitem, dt, 3.0)
+
+        assert_equal(dt[1], dt[np.int8(1)])
+
+    @pytest.mark.parametrize('align_flag',[False, True])
+    def test_multifield_index(self, align_flag):
+        # indexing with a list produces subfields
+        # the align flag should be preserved
+        dt = np.dtype([
+            (('title', 'col1'), '<U20'), ('A', '<f8'), ('B', '<f8')
+        ], align=align_flag)
+
+        dt_sub = dt[['B', 'col1']]
+        assert_equal(
+            dt_sub,
+            np.dtype({
+                'names': ['B', 'col1'],
+                'formats': ['<f8', '<U20'],
+                'offsets': [88, 0],
+                'titles': [None, 'title'],
+                'itemsize': 96
+            })
+        )
+        assert_equal(dt_sub.isalignedstruct, align_flag)
+
+        dt_sub = dt[['B']]
+        assert_equal(
+            dt_sub,
+            np.dtype({
+                'names': ['B'],
+                'formats': ['<f8'],
+                'offsets': [88],
+                'itemsize': 96
+            })
+        )
+        assert_equal(dt_sub.isalignedstruct, align_flag)
+
+        dt_sub = dt[[]]
+        assert_equal(
+            dt_sub,
+            np.dtype({
+                'names': [],
+                'formats': [],
+                'offsets': [],
+                'itemsize': 96
+            })
+        )
+        assert_equal(dt_sub.isalignedstruct, align_flag)
+
+        assert_raises(TypeError, operator.getitem, dt, ())
+        assert_raises(TypeError, operator.getitem, dt, [1, 2, 3])
+        assert_raises(TypeError, operator.getitem, dt, ['col1', 2])
+        assert_raises(KeyError, operator.getitem, dt, ['fake'])
+        assert_raises(KeyError, operator.getitem, dt, ['title'])
+        assert_raises(ValueError, operator.getitem, dt, ['col1', 'col1'])
+
+    def test_partial_dict(self):
+        # 'names' is missing
+        assert_raises(ValueError, np.dtype,
+                {'formats': ['i4', 'i4'], 'f0': ('i4', 0), 'f1':('i4', 4)})
+
+    def test_fieldless_views(self):
+        a = np.zeros(2, dtype={'names':[], 'formats':[], 'offsets':[],
+                               'itemsize':8})
+        assert_raises(ValueError, a.view, np.dtype([]))
+
+        d = np.dtype((np.dtype([]), 10))
+        assert_equal(d.shape, (10,))
+        assert_equal(d.itemsize, 0)
+        assert_equal(d.base, np.dtype([]))
+
+        arr = np.fromiter((() for i in range(10)), [])
+        assert_equal(arr.dtype, np.dtype([]))
+        assert_raises(ValueError, np.frombuffer, b'', dtype=[])
+        assert_equal(np.frombuffer(b'', dtype=[], count=2),
+                     np.empty(2, dtype=[]))
+
+        assert_raises(ValueError, np.dtype, ([], 'f8'))
+        assert_raises(ValueError, np.zeros(1, dtype='i4').view, [])
+
+        assert_equal(np.zeros(2, dtype=[]) == np.zeros(2, dtype=[]),
+                     np.ones(2, dtype=bool))
+
+        assert_equal(np.zeros((1, 2), dtype=[]) == a,
+                     np.ones((1, 2), dtype=bool))
+
+    def test_nonstructured_with_object(self):
+        # See gh-23277, the dtype here thinks it contain objects, if the
+        # assert about that fails, the test becomes meaningless (which is OK)
+        arr = np.recarray((0,), dtype="O") 
+        assert arr.dtype.names is None  # no fields
+        assert arr.dtype.hasobject  # but claims to contain objects
+        del arr  # the deletion failed previously.
+
+
+class TestSubarray:
+    def test_single_subarray(self):
+        a = np.dtype((int, (2)))
+        b = np.dtype((int, (2,)))
+        assert_dtype_equal(a, b)
+
+        assert_equal(type(a.subdtype[1]), tuple)
+        assert_equal(type(b.subdtype[1]), tuple)
+
+    def test_equivalent_record(self):
+        """Test whether equivalent subarray dtypes hash the same."""
+        a = np.dtype((int, (2, 3)))
+        b = np.dtype((int, (2, 3)))
+        assert_dtype_equal(a, b)
+
+    def test_nonequivalent_record(self):
+        """Test whether different subarray dtypes hash differently."""
+        a = np.dtype((int, (2, 3)))
+        b = np.dtype((int, (3, 2)))
+        assert_dtype_not_equal(a, b)
+
+        a = np.dtype((int, (2, 3)))
+        b = np.dtype((int, (2, 2)))
+        assert_dtype_not_equal(a, b)
+
+        a = np.dtype((int, (1, 2, 3)))
+        b = np.dtype((int, (1, 2)))
+        assert_dtype_not_equal(a, b)
+
+    def test_shape_equal(self):
+        """Test some data types that are equal"""
+        assert_dtype_equal(np.dtype('f8'), np.dtype(('f8', tuple())))
+        # FutureWarning during deprecation period; after it is passed this
+        # should instead check that "(1)f8" == "1f8" == ("f8", 1).
+        with pytest.warns(FutureWarning):
+            assert_dtype_equal(np.dtype('f8'), np.dtype(('f8', 1)))
+        assert_dtype_equal(np.dtype((int, 2)), np.dtype((int, (2,))))
+        assert_dtype_equal(np.dtype(('<f4', (3, 2))), np.dtype(('<f4', (3, 2))))
+        d = ([('a', 'f4', (1, 2)), ('b', 'f8', (3, 1))], (3, 2))
+        assert_dtype_equal(np.dtype(d), np.dtype(d))
+
+    def test_shape_simple(self):
+        """Test some simple cases that shouldn't be equal"""
+        assert_dtype_not_equal(np.dtype('f8'), np.dtype(('f8', (1,))))
+        assert_dtype_not_equal(np.dtype(('f8', (1,))), np.dtype(('f8', (1, 1))))
+        assert_dtype_not_equal(np.dtype(('f4', (3, 2))), np.dtype(('f4', (2, 3))))
+
+    def test_shape_monster(self):
+        """Test some more complicated cases that shouldn't be equal"""
+        assert_dtype_not_equal(
+            np.dtype(([('a', 'f4', (2, 1)), ('b', 'f8', (1, 3))], (2, 2))),
+            np.dtype(([('a', 'f4', (1, 2)), ('b', 'f8', (1, 3))], (2, 2))))
+        assert_dtype_not_equal(
+            np.dtype(([('a', 'f4', (2, 1)), ('b', 'f8', (1, 3))], (2, 2))),
+            np.dtype(([('a', 'f4', (2, 1)), ('b', 'i8', (1, 3))], (2, 2))))
+        assert_dtype_not_equal(
+            np.dtype(([('a', 'f4', (2, 1)), ('b', 'f8', (1, 3))], (2, 2))),
+            np.dtype(([('e', 'f8', (1, 3)), ('d', 'f4', (2, 1))], (2, 2))))
+        assert_dtype_not_equal(
+            np.dtype(([('a', [('a', 'i4', 6)], (2, 1)), ('b', 'f8', (1, 3))], (2, 2))),
+            np.dtype(([('a', [('a', 'u4', 6)], (2, 1)), ('b', 'f8', (1, 3))], (2, 2))))
+
+    def test_shape_sequence(self):
+        # Any sequence of integers should work as shape, but the result
+        # should be a tuple (immutable) of base type integers.
+        a = np.array([1, 2, 3], dtype=np.int16)
+        l = [1, 2, 3]
+        # Array gets converted
+        dt = np.dtype([('a', 'f4', a)])
+        assert_(isinstance(dt['a'].shape, tuple))
+        assert_(isinstance(dt['a'].shape[0], int))
+        # List gets converted
+        dt = np.dtype([('a', 'f4', l)])
+        assert_(isinstance(dt['a'].shape, tuple))
+        #
+
+        class IntLike:
+            def __index__(self):
+                return 3
+
+            def __int__(self):
+                # (a PyNumber_Check fails without __int__)
+                return 3
+
+        dt = np.dtype([('a', 'f4', IntLike())])
+        assert_(isinstance(dt['a'].shape, tuple))
+        assert_(isinstance(dt['a'].shape[0], int))
+        dt = np.dtype([('a', 'f4', (IntLike(),))])
+        assert_(isinstance(dt['a'].shape, tuple))
+        assert_(isinstance(dt['a'].shape[0], int))
+
+    def test_shape_matches_ndim(self):
+        dt = np.dtype([('a', 'f4', ())])
+        assert_equal(dt['a'].shape, ())
+        assert_equal(dt['a'].ndim, 0)
+
+        dt = np.dtype([('a', 'f4')])
+        assert_equal(dt['a'].shape, ())
+        assert_equal(dt['a'].ndim, 0)
+
+        dt = np.dtype([('a', 'f4', 4)])
+        assert_equal(dt['a'].shape, (4,))
+        assert_equal(dt['a'].ndim, 1)
+
+        dt = np.dtype([('a', 'f4', (1, 2, 3))])
+        assert_equal(dt['a'].shape, (1, 2, 3))
+        assert_equal(dt['a'].ndim, 3)
+
+    def test_shape_invalid(self):
+        # Check that the shape is valid.
+        max_int = np.iinfo(np.intc).max
+        max_intp = np.iinfo(np.intp).max
+        # Too large values (the datatype is part of this)
+        assert_raises(ValueError, np.dtype, [('a', 'f4', max_int // 4 + 1)])
+        assert_raises(ValueError, np.dtype, [('a', 'f4', max_int + 1)])
+        assert_raises(ValueError, np.dtype, [('a', 'f4', (max_int, 2))])
+        # Takes a different code path (fails earlier:
+        assert_raises(ValueError, np.dtype, [('a', 'f4', max_intp + 1)])
+        # Negative values
+        assert_raises(ValueError, np.dtype, [('a', 'f4', -1)])
+        assert_raises(ValueError, np.dtype, [('a', 'f4', (-1, -1))])
+
+    def test_alignment(self):
+        #Check that subarrays are aligned
+        t1 = np.dtype('(1,)i4', align=True)
+        t2 = np.dtype('2i4', align=True)
+        assert_equal(t1.alignment, t2.alignment)
+
+    def test_aligned_empty(self):
+        # Mainly regression test for gh-19696: construction failed completely
+        dt = np.dtype([], align=True)
+        assert dt == np.dtype([])
+        dt = np.dtype({"names": [], "formats": [], "itemsize": 0}, align=True)
+        assert dt == np.dtype([])
+
+    def test_subarray_base_item(self):
+        arr = np.ones(3, dtype=[("f", "i", 3)])
+        # Extracting the field "absorbs" the subarray into a view:
+        assert arr["f"].base is arr
+        # Extract the structured item, and then check the tuple component:
+        item = arr.item(0)
+        assert type(item) is tuple and len(item) == 1
+        assert item[0].base is arr
+
+    def test_subarray_cast_copies(self):
+        # Older versions of NumPy did NOT copy, but they got the ownership
+        # wrong (not actually knowing the correct base!).  Versions since 1.21
+        # (I think) crashed fairly reliable.  This defines the correct behavior
+        # as a copy.  Keeping the ownership would be possible (but harder)
+        arr = np.ones(3, dtype=[("f", "i", 3)])
+        cast = arr.astype(object)
+        for fields in cast:
+            assert type(fields) == tuple and len(fields) == 1
+            subarr = fields[0]
+            assert subarr.base is None
+            assert subarr.flags.owndata
+
+
+def iter_struct_object_dtypes():
+    """
+    Iterates over a few complex dtypes and object pattern which
+    fill the array with a given object (defaults to a singleton).
+
+    Yields
+    ------
+    dtype : dtype
+    pattern : tuple
+        Structured tuple for use with `np.array`.
+    count : int
+        Number of objects stored in the dtype.
+    singleton : object
+        A singleton object. The returned pattern is constructed so that
+        all objects inside the datatype are set to the singleton.
+    """
+    obj = object()
+
+    dt = np.dtype([('b', 'O', (2, 3))])
+    p = ([[obj] * 3] * 2,)
+    yield pytest.param(dt, p, 6, obj, id="<subarray>")
+
+    dt = np.dtype([('a', 'i4'), ('b', 'O', (2, 3))])
+    p = (0, [[obj] * 3] * 2)
+    yield pytest.param(dt, p, 6, obj, id="<subarray in field>")
+
+    dt = np.dtype([('a', 'i4'),
+                   ('b', [('ba', 'O'), ('bb', 'i1')], (2, 3))])
+    p = (0, [[(obj, 0)] * 3] * 2)
+    yield pytest.param(dt, p, 6, obj, id="<structured subarray 1>")
+
+    dt = np.dtype([('a', 'i4'),
+                   ('b', [('ba', 'O'), ('bb', 'O')], (2, 3))])
+    p = (0, [[(obj, obj)] * 3] * 2)
+    yield pytest.param(dt, p, 12, obj, id="<structured subarray 2>")
+
+
+@pytest.mark.skipif(
+    sys.version_info >= (3, 12),
+    reason="Python 3.12 has immortal refcounts, this test will no longer "
+           "work. See gh-23986"
+)
+@pytest.mark.skipif(not HAS_REFCOUNT, reason="Python lacks refcounts")
+class TestStructuredObjectRefcounting:
+    """These tests cover various uses of complicated structured types which
+    include objects and thus require reference counting.
+    """
+    @pytest.mark.parametrize(['dt', 'pat', 'count', 'singleton'],
+                             iter_struct_object_dtypes())
+    @pytest.mark.parametrize(["creation_func", "creation_obj"], [
+        pytest.param(np.empty, None,
+             # None is probably used for too many things
+             marks=pytest.mark.skip("unreliable due to python's behaviour")),
+        (np.ones, 1),
+        (np.zeros, 0)])
+    def test_structured_object_create_delete(self, dt, pat, count, singleton,
+                                             creation_func, creation_obj):
+        """Structured object reference counting in creation and deletion"""
+        # The test assumes that 0, 1, and None are singletons.
+        gc.collect()
+        before = sys.getrefcount(creation_obj)
+        arr = creation_func(3, dt)
+
+        now = sys.getrefcount(creation_obj)
+        assert now - before == count * 3
+        del arr
+        now = sys.getrefcount(creation_obj)
+        assert now == before
+
+    @pytest.mark.parametrize(['dt', 'pat', 'count', 'singleton'],
+                             iter_struct_object_dtypes())
+    def test_structured_object_item_setting(self, dt, pat, count, singleton):
+        """Structured object reference counting for simple item setting"""
+        one = 1
+
+        gc.collect()
+        before = sys.getrefcount(singleton)
+        arr = np.array([pat] * 3, dt)
+        assert sys.getrefcount(singleton) - before == count * 3
+        # Fill with `1` and check that it was replaced correctly:
+        before2 = sys.getrefcount(one)
+        arr[...] = one
+        after2 = sys.getrefcount(one)
+        assert after2 - before2 == count * 3
+        del arr
+        gc.collect()
+        assert sys.getrefcount(one) == before2
+        assert sys.getrefcount(singleton) == before
+
+    @pytest.mark.parametrize(['dt', 'pat', 'count', 'singleton'],
+                             iter_struct_object_dtypes())
+    @pytest.mark.parametrize(
+        ['shape', 'index', 'items_changed'],
+        [((3,), ([0, 2],), 2),
+         ((3, 2), ([0, 2], slice(None)), 4),
+         ((3, 2), ([0, 2], [1]), 2),
+         ((3,), ([True, False, True]), 2)])
+    def test_structured_object_indexing(self, shape, index, items_changed,
+                                        dt, pat, count, singleton):
+        """Structured object reference counting for advanced indexing."""
+        # Use two small negative values (should be singletons, but less likely
+        # to run into race-conditions).  This failed in some threaded envs
+        # When using 0 and 1.  If it fails again, should remove all explicit
+        # checks, and rely on `pytest-leaks` reference count checker only.
+        val0 = -4
+        val1 = -5
+
+        arr = np.full(shape, val0, dt)
+
+        gc.collect()
+        before_val0 = sys.getrefcount(val0)
+        before_val1 = sys.getrefcount(val1)
+        # Test item getting:
+        part = arr[index]
+        after_val0 = sys.getrefcount(val0)
+        assert after_val0 - before_val0 == count * items_changed
+        del part
+        # Test item setting:
+        arr[index] = val1
+        gc.collect()
+        after_val0 = sys.getrefcount(val0)
+        after_val1 = sys.getrefcount(val1)
+        assert before_val0 - after_val0 == count * items_changed
+        assert after_val1 - before_val1 == count * items_changed
+
+    @pytest.mark.parametrize(['dt', 'pat', 'count', 'singleton'],
+                             iter_struct_object_dtypes())
+    def test_structured_object_take_and_repeat(self, dt, pat, count, singleton):
+        """Structured object reference counting for specialized functions.
+        The older functions such as take and repeat use different code paths
+        then item setting (when writing this).
+        """
+        indices = [0, 1]
+
+        arr = np.array([pat] * 3, dt)
+        gc.collect()
+        before = sys.getrefcount(singleton)
+        res = arr.take(indices)
+        after = sys.getrefcount(singleton)
+        assert after - before == count * 2
+        new = res.repeat(10)
+        gc.collect()
+        after_repeat = sys.getrefcount(singleton)
+        assert after_repeat - after == count * 2 * 10
+
+
+class TestStructuredDtypeSparseFields:
+    """Tests subarray fields which contain sparse dtypes so that
+    not all memory is used by the dtype work. Such dtype's should
+    leave the underlying memory unchanged.
+    """
+    dtype = np.dtype([('a', {'names':['aa', 'ab'], 'formats':['f', 'f'],
+                             'offsets':[0, 4]}, (2, 3))])
+    sparse_dtype = np.dtype([('a', {'names':['ab'], 'formats':['f'],
+                                    'offsets':[4]}, (2, 3))])
+
+    def test_sparse_field_assignment(self):
+        arr = np.zeros(3, self.dtype)
+        sparse_arr = arr.view(self.sparse_dtype)
+
+        sparse_arr[...] = np.finfo(np.float32).max
+        # dtype is reduced when accessing the field, so shape is (3, 2, 3):
+        assert_array_equal(arr["a"]["aa"], np.zeros((3, 2, 3)))
+
+    def test_sparse_field_assignment_fancy(self):
+        # Fancy assignment goes to the copyswap function for complex types:
+        arr = np.zeros(3, self.dtype)
+        sparse_arr = arr.view(self.sparse_dtype)
+
+        sparse_arr[[0, 1, 2]] = np.finfo(np.float32).max
+        # dtype is reduced when accessing the field, so shape is (3, 2, 3):
+        assert_array_equal(arr["a"]["aa"], np.zeros((3, 2, 3)))
+
+
+class TestMonsterType:
+    """Test deeply nested subtypes."""
+
+    def test1(self):
+        simple1 = np.dtype({'names': ['r', 'b'], 'formats': ['u1', 'u1'],
+            'titles': ['Red pixel', 'Blue pixel']})
+        a = np.dtype([('yo', int), ('ye', simple1),
+            ('yi', np.dtype((int, (3, 2))))])
+        b = np.dtype([('yo', int), ('ye', simple1),
+            ('yi', np.dtype((int, (3, 2))))])
+        assert_dtype_equal(a, b)
+
+        c = np.dtype([('yo', int), ('ye', simple1),
+            ('yi', np.dtype((a, (3, 2))))])
+        d = np.dtype([('yo', int), ('ye', simple1),
+            ('yi', np.dtype((a, (3, 2))))])
+        assert_dtype_equal(c, d)
+
+    @pytest.mark.skipif(IS_PYSTON, reason="Pyston disables recursion checking")
+    def test_list_recursion(self):
+        l = list()
+        l.append(('f', l))
+        with pytest.raises(RecursionError):
+            np.dtype(l)
+
+    @pytest.mark.skipif(IS_PYSTON, reason="Pyston disables recursion checking")
+    def test_tuple_recursion(self):
+        d = np.int32
+        for i in range(100000):
+            d = (d, (1,))
+        with pytest.raises(RecursionError):
+            np.dtype(d)
+
+    @pytest.mark.skipif(IS_PYSTON, reason="Pyston disables recursion checking")
+    def test_dict_recursion(self):
+        d = dict(names=['self'], formats=[None], offsets=[0])
+        d['formats'][0] = d
+        with pytest.raises(RecursionError):
+            np.dtype(d)
+
+
+class TestMetadata:
+    def test_no_metadata(self):
+        d = np.dtype(int)
+        assert_(d.metadata is None)
+
+    def test_metadata_takes_dict(self):
+        d = np.dtype(int, metadata={'datum': 1})
+        assert_(d.metadata == {'datum': 1})
+
+    def test_metadata_rejects_nondict(self):
+        assert_raises(TypeError, np.dtype, int, metadata='datum')
+        assert_raises(TypeError, np.dtype, int, metadata=1)
+        assert_raises(TypeError, np.dtype, int, metadata=None)
+
+    def test_nested_metadata(self):
+        d = np.dtype([('a', np.dtype(int, metadata={'datum': 1}))])
+        assert_(d['a'].metadata == {'datum': 1})
+
+    def test_base_metadata_copied(self):
+        d = np.dtype((np.void, np.dtype('i4,i4', metadata={'datum': 1})))
+        assert_(d.metadata == {'datum': 1})
+
+class TestString:
+    def test_complex_dtype_str(self):
+        dt = np.dtype([('top', [('tiles', ('>f4', (64, 64)), (1,)),
+                                ('rtile', '>f4', (64, 36))], (3,)),
+                       ('bottom', [('bleft', ('>f4', (8, 64)), (1,)),
+                                   ('bright', '>f4', (8, 36))])])
+        assert_equal(str(dt),
+                     "[('top', [('tiles', ('>f4', (64, 64)), (1,)), "
+                     "('rtile', '>f4', (64, 36))], (3,)), "
+                     "('bottom', [('bleft', ('>f4', (8, 64)), (1,)), "
+                     "('bright', '>f4', (8, 36))])]")
+
+        # If the sticky aligned flag is set to True, it makes the
+        # str() function use a dict representation with an 'aligned' flag
+        dt = np.dtype([('top', [('tiles', ('>f4', (64, 64)), (1,)),
+                                ('rtile', '>f4', (64, 36))],
+                                (3,)),
+                       ('bottom', [('bleft', ('>f4', (8, 64)), (1,)),
+                                   ('bright', '>f4', (8, 36))])],
+                       align=True)
+        assert_equal(str(dt),
+                    "{'names': ['top', 'bottom'],"
+                    " 'formats': [([('tiles', ('>f4', (64, 64)), (1,)), "
+                                   "('rtile', '>f4', (64, 36))], (3,)), "
+                                  "[('bleft', ('>f4', (8, 64)), (1,)), "
+                                   "('bright', '>f4', (8, 36))]],"
+                    " 'offsets': [0, 76800],"
+                    " 'itemsize': 80000,"
+                    " 'aligned': True}")
+        with np.printoptions(legacy='1.21'):
+            assert_equal(str(dt),
+                        "{'names':['top','bottom'], "
+                         "'formats':[([('tiles', ('>f4', (64, 64)), (1,)), "
+                                      "('rtile', '>f4', (64, 36))], (3,)),"
+                                     "[('bleft', ('>f4', (8, 64)), (1,)), "
+                                      "('bright', '>f4', (8, 36))]], "
+                         "'offsets':[0,76800], "
+                         "'itemsize':80000, "
+                         "'aligned':True}")
+        assert_equal(np.dtype(eval(str(dt))), dt)
+
+        dt = np.dtype({'names': ['r', 'g', 'b'], 'formats': ['u1', 'u1', 'u1'],
+                        'offsets': [0, 1, 2],
+                        'titles': ['Red pixel', 'Green pixel', 'Blue pixel']})
+        assert_equal(str(dt),
+                    "[(('Red pixel', 'r'), 'u1'), "
+                    "(('Green pixel', 'g'), 'u1'), "
+                    "(('Blue pixel', 'b'), 'u1')]")
+
+        dt = np.dtype({'names': ['rgba', 'r', 'g', 'b'],
+                       'formats': ['<u4', 'u1', 'u1', 'u1'],
+                       'offsets': [0, 0, 1, 2],
+                       'titles': ['Color', 'Red pixel',
+                                  'Green pixel', 'Blue pixel']})
+        assert_equal(str(dt),
+                    "{'names': ['rgba', 'r', 'g', 'b'],"
+                    " 'formats': ['<u4', 'u1', 'u1', 'u1'],"
+                    " 'offsets': [0, 0, 1, 2],"
+                    " 'titles': ['Color', 'Red pixel', "
+                               "'Green pixel', 'Blue pixel'],"
+                    " 'itemsize': 4}")
+
+        dt = np.dtype({'names': ['r', 'b'], 'formats': ['u1', 'u1'],
+                        'offsets': [0, 2],
+                        'titles': ['Red pixel', 'Blue pixel']})
+        assert_equal(str(dt),
+                    "{'names': ['r', 'b'],"
+                    " 'formats': ['u1', 'u1'],"
+                    " 'offsets': [0, 2],"
+                    " 'titles': ['Red pixel', 'Blue pixel'],"
+                    " 'itemsize': 3}")
+
+        dt = np.dtype([('a', '<m8[D]'), ('b', '<M8[us]')])
+        assert_equal(str(dt),
+                    "[('a', '<m8[D]'), ('b', '<M8[us]')]")
+
+    def test_repr_structured(self):
+        dt = np.dtype([('top', [('tiles', ('>f4', (64, 64)), (1,)),
+                                ('rtile', '>f4', (64, 36))], (3,)),
+                       ('bottom', [('bleft', ('>f4', (8, 64)), (1,)),
+                                   ('bright', '>f4', (8, 36))])])
+        assert_equal(repr(dt),
+                     "dtype([('top', [('tiles', ('>f4', (64, 64)), (1,)), "
+                     "('rtile', '>f4', (64, 36))], (3,)), "
+                     "('bottom', [('bleft', ('>f4', (8, 64)), (1,)), "
+                     "('bright', '>f4', (8, 36))])])")
+
+        dt = np.dtype({'names': ['r', 'g', 'b'], 'formats': ['u1', 'u1', 'u1'],
+                        'offsets': [0, 1, 2],
+                        'titles': ['Red pixel', 'Green pixel', 'Blue pixel']},
+                        align=True)
+        assert_equal(repr(dt),
+                    "dtype([(('Red pixel', 'r'), 'u1'), "
+                    "(('Green pixel', 'g'), 'u1'), "
+                    "(('Blue pixel', 'b'), 'u1')], align=True)")
+
+    def test_repr_structured_not_packed(self):
+        dt = np.dtype({'names': ['rgba', 'r', 'g', 'b'],
+                       'formats': ['<u4', 'u1', 'u1', 'u1'],
+                       'offsets': [0, 0, 1, 2],
+                       'titles': ['Color', 'Red pixel',
+                                  'Green pixel', 'Blue pixel']}, align=True)
+        assert_equal(repr(dt),
+                    "dtype({'names': ['rgba', 'r', 'g', 'b'],"
+                    " 'formats': ['<u4', 'u1', 'u1', 'u1'],"
+                    " 'offsets': [0, 0, 1, 2],"
+                    " 'titles': ['Color', 'Red pixel', "
+                                "'Green pixel', 'Blue pixel'],"
+                    " 'itemsize': 4}, align=True)")
+
+        dt = np.dtype({'names': ['r', 'b'], 'formats': ['u1', 'u1'],
+                        'offsets': [0, 2],
+                        'titles': ['Red pixel', 'Blue pixel'],
+                        'itemsize': 4})
+        assert_equal(repr(dt),
+                    "dtype({'names': ['r', 'b'], "
+                    "'formats': ['u1', 'u1'], "
+                    "'offsets': [0, 2], "
+                    "'titles': ['Red pixel', 'Blue pixel'], "
+                    "'itemsize': 4})")
+
+    def test_repr_structured_datetime(self):
+        dt = np.dtype([('a', '<M8[D]'), ('b', '<m8[us]')])
+        assert_equal(repr(dt),
+                    "dtype([('a', '<M8[D]'), ('b', '<m8[us]')])")
+
+    def test_repr_str_subarray(self):
+        dt = np.dtype(('<i2', (1,)))
+        assert_equal(repr(dt), "dtype(('<i2', (1,)))")
+        assert_equal(str(dt), "('<i2', (1,))")
+
+    def test_base_dtype_with_object_type(self):
+        # Issue gh-2798, should not error.
+        np.array(['a'], dtype="O").astype(("O", [("name", "O")]))
+
+    def test_empty_string_to_object(self):
+        # Pull request #4722
+        np.array(["", ""]).astype(object)
+
+    def test_void_subclass_unsized(self):
+        dt = np.dtype(np.record)
+        assert_equal(repr(dt), "dtype('V')")
+        assert_equal(str(dt), '|V0')
+        assert_equal(dt.name, 'record')
+
+    def test_void_subclass_sized(self):
+        dt = np.dtype((np.record, 2))
+        assert_equal(repr(dt), "dtype('V2')")
+        assert_equal(str(dt), '|V2')
+        assert_equal(dt.name, 'record16')
+
+    def test_void_subclass_fields(self):
+        dt = np.dtype((np.record, [('a', '<u2')]))
+        assert_equal(repr(dt), "dtype((numpy.record, [('a', '<u2')]))")
+        assert_equal(str(dt), "(numpy.record, [('a', '<u2')])")
+        assert_equal(dt.name, 'record16')
+
+
+class TestDtypeAttributeDeletion:
+
+    def test_dtype_non_writable_attributes_deletion(self):
+        dt = np.dtype(np.double)
+        attr = ["subdtype", "descr", "str", "name", "base", "shape",
+                "isbuiltin", "isnative", "isalignedstruct", "fields",
+                "metadata", "hasobject"]
+
+        for s in attr:
+            assert_raises(AttributeError, delattr, dt, s)
+
+    def test_dtype_writable_attributes_deletion(self):
+        dt = np.dtype(np.double)
+        attr = ["names"]
+        for s in attr:
+            assert_raises(AttributeError, delattr, dt, s)
+
+
+class TestDtypeAttributes:
+    def test_descr_has_trailing_void(self):
+        # see gh-6359
+        dtype = np.dtype({
+            'names': ['A', 'B'],
+            'formats': ['f4', 'f4'],
+            'offsets': [0, 8],
+            'itemsize': 16})
+        new_dtype = np.dtype(dtype.descr)
+        assert_equal(new_dtype.itemsize, 16)
+
+    def test_name_dtype_subclass(self):
+        # Ticket #4357
+        class user_def_subcls(np.void):
+            pass
+        assert_equal(np.dtype(user_def_subcls).name, 'user_def_subcls')
+
+    def test_zero_stride(self):
+        arr = np.ones(1, dtype="i8")
+        arr = np.broadcast_to(arr, 10)
+        assert arr.strides == (0,)
+        with pytest.raises(ValueError):
+            arr.dtype = "i1"
+
+class TestDTypeMakeCanonical:
+    def check_canonical(self, dtype, canonical):
+        """
+        Check most properties relevant to "canonical" versions of a dtype,
+        which is mainly native byte order for datatypes supporting this.
+
+        The main work is checking structured dtypes with fields, where we
+        reproduce most the actual logic used in the C-code.
+        """
+        assert type(dtype) is type(canonical)
+
+        # a canonical DType should always have equivalent casting (both ways)
+        assert np.can_cast(dtype, canonical, casting="equiv")
+        assert np.can_cast(canonical, dtype, casting="equiv")
+        # a canonical dtype (and its fields) is always native (checks fields):
+        assert canonical.isnative
+
+        # Check that canonical of canonical is the same (no casting):
+        assert np.result_type(canonical) == canonical
+
+        if not dtype.names:
+            # The flags currently never change for unstructured dtypes
+            assert dtype.flags == canonical.flags
+            return
+
+        # Must have all the needs API flag set:
+        assert dtype.flags & 0b10000
+
+        # Check that the fields are identical (including titles):
+        assert dtype.fields.keys() == canonical.fields.keys()
+
+        def aligned_offset(offset, alignment):
+            # round up offset:
+            return - (-offset // alignment) * alignment
+
+        totalsize = 0
+        max_alignment = 1
+        for name in dtype.names:
+            # each field is also canonical:
+            new_field_descr = canonical.fields[name][0]
+            self.check_canonical(dtype.fields[name][0], new_field_descr)
+
+            # Must have the "inherited" object related flags:
+            expected = 0b11011 & new_field_descr.flags
+            assert (canonical.flags & expected) == expected
+
+            if canonical.isalignedstruct:
+                totalsize = aligned_offset(totalsize, new_field_descr.alignment)
+                max_alignment = max(new_field_descr.alignment, max_alignment)
+
+            assert canonical.fields[name][1] == totalsize
+            # if a title exists, they must match (otherwise empty tuple):
+            assert dtype.fields[name][2:] == canonical.fields[name][2:]
+
+            totalsize += new_field_descr.itemsize
+
+        if canonical.isalignedstruct:
+            totalsize = aligned_offset(totalsize, max_alignment)
+        assert canonical.itemsize == totalsize
+        assert canonical.alignment == max_alignment
+
+    def test_simple(self):
+        dt = np.dtype(">i4")
+        assert np.result_type(dt).isnative
+        assert np.result_type(dt).num == dt.num
+
+        # dtype with empty space:
+        struct_dt = np.dtype(">i4,<i1,i8,V3")[["f0", "f2"]]
+        canonical = np.result_type(struct_dt)
+        assert canonical.itemsize == 4+8
+        assert canonical.isnative
+
+        # aligned struct dtype with empty space:
+        struct_dt = np.dtype(">i1,<i4,i8,V3", align=True)[["f0", "f2"]]
+        canonical = np.result_type(struct_dt)
+        assert canonical.isalignedstruct
+        assert canonical.itemsize == np.dtype("i8").alignment + 8
+        assert canonical.isnative
+
+    def test_object_flag_not_inherited(self):
+        # The following dtype still indicates "object", because its included
+        # in the unaccessible space (maybe this could change at some point):
+        arr = np.ones(3, "i,O,i")[["f0", "f2"]]
+        assert arr.dtype.hasobject
+        canonical_dt = np.result_type(arr.dtype)
+        assert not canonical_dt.hasobject
+
+    @pytest.mark.slow
+    @hypothesis.given(dtype=hynp.nested_dtypes())
+    def test_make_canonical_hypothesis(self, dtype):
+        canonical = np.result_type(dtype)
+        self.check_canonical(dtype, canonical)
+        # result_type with two arguments should always give identical results:
+        two_arg_result = np.result_type(dtype, dtype)
+        assert np.can_cast(two_arg_result, canonical, casting="no")
+
+    @pytest.mark.slow
+    @hypothesis.given(
+            dtype=hypothesis.extra.numpy.array_dtypes(
+                subtype_strategy=hypothesis.extra.numpy.array_dtypes(),
+                min_size=5, max_size=10, allow_subarrays=True))
+    def test_structured(self, dtype):
+        # Pick 4 of the fields at random.  This will leave empty space in the
+        # dtype (since we do not canonicalize it here).
+        field_subset = random.sample(dtype.names, k=4)
+        dtype_with_empty_space = dtype[field_subset]
+        assert dtype_with_empty_space.itemsize == dtype.itemsize
+        canonicalized = np.result_type(dtype_with_empty_space)
+        self.check_canonical(dtype_with_empty_space, canonicalized)
+        # promotion with two arguments should always give identical results:
+        two_arg_result = np.promote_types(
+                dtype_with_empty_space, dtype_with_empty_space)
+        assert np.can_cast(two_arg_result, canonicalized, casting="no")
+
+        # Ensure that we also check aligned struct (check the opposite, in
+        # case hypothesis grows support for `align`.  Then repeat the test:
+        dtype_aligned = np.dtype(dtype.descr, align=not dtype.isalignedstruct)
+        dtype_with_empty_space = dtype_aligned[field_subset]
+        assert dtype_with_empty_space.itemsize == dtype_aligned.itemsize
+        canonicalized = np.result_type(dtype_with_empty_space)
+        self.check_canonical(dtype_with_empty_space, canonicalized)
+        # promotion with two arguments should always give identical results:
+        two_arg_result = np.promote_types(
+            dtype_with_empty_space, dtype_with_empty_space)
+        assert np.can_cast(two_arg_result, canonicalized, casting="no")
+
+
+class TestPickling:
+
+    def check_pickling(self, dtype):
+        for proto in range(pickle.HIGHEST_PROTOCOL + 1):
+            buf = pickle.dumps(dtype, proto)
+            # The dtype pickling itself pickles `np.dtype` if it is pickled
+            # as a singleton `dtype` should be stored in the buffer:
+            assert b"_DType_reconstruct" not in buf
+            assert b"dtype" in buf
+            pickled = pickle.loads(buf)
+            assert_equal(pickled, dtype)
+            assert_equal(pickled.descr, dtype.descr)
+            if dtype.metadata is not None:
+                assert_equal(pickled.metadata, dtype.metadata)
+            # Check the reconstructed dtype is functional
+            x = np.zeros(3, dtype=dtype)
+            y = np.zeros(3, dtype=pickled)
+            assert_equal(x, y)
+            assert_equal(x[0], y[0])
+
+    @pytest.mark.parametrize('t', [int, float, complex, np.int32, str, object,
+                                   np.compat.unicode, bool])
+    def test_builtin(self, t):
+        self.check_pickling(np.dtype(t))
+
+    def test_structured(self):
+        dt = np.dtype(([('a', '>f4', (2, 1)), ('b', '<f8', (1, 3))], (2, 2)))
+        self.check_pickling(dt)
+
+    def test_structured_aligned(self):
+        dt = np.dtype('i4, i1', align=True)
+        self.check_pickling(dt)
+
+    def test_structured_unaligned(self):
+        dt = np.dtype('i4, i1', align=False)
+        self.check_pickling(dt)
+
+    def test_structured_padded(self):
+        dt = np.dtype({
+            'names': ['A', 'B'],
+            'formats': ['f4', 'f4'],
+            'offsets': [0, 8],
+            'itemsize': 16})
+        self.check_pickling(dt)
+
+    def test_structured_titles(self):
+        dt = np.dtype({'names': ['r', 'b'],
+                       'formats': ['u1', 'u1'],
+                       'titles': ['Red pixel', 'Blue pixel']})
+        self.check_pickling(dt)
+
+    @pytest.mark.parametrize('base', ['m8', 'M8'])
+    @pytest.mark.parametrize('unit', ['', 'Y', 'M', 'W', 'D', 'h', 'm', 's',
+                                      'ms', 'us', 'ns', 'ps', 'fs', 'as'])
+    def test_datetime(self, base, unit):
+        dt = np.dtype('%s[%s]' % (base, unit) if unit else base)
+        self.check_pickling(dt)
+        if unit:
+            dt = np.dtype('%s[7%s]' % (base, unit))
+            self.check_pickling(dt)
+
+    def test_metadata(self):
+        dt = np.dtype(int, metadata={'datum': 1})
+        self.check_pickling(dt)
+
+    @pytest.mark.parametrize("DType",
+        [type(np.dtype(t)) for t in np.typecodes['All']] +
+        [np.dtype(rational), np.dtype])
+    def test_pickle_types(self, DType):
+        # Check that DTypes (the classes/types) roundtrip when pickling
+        for proto in range(pickle.HIGHEST_PROTOCOL + 1):
+            roundtrip_DType = pickle.loads(pickle.dumps(DType, proto))
+            assert roundtrip_DType is DType
+
+
+class TestPromotion:
+    """Test cases related to more complex DType promotions.  Further promotion
+    tests are defined in `test_numeric.py`
+    """
+    @np._no_nep50_warning()
+    @pytest.mark.parametrize(["other", "expected", "expected_weak"],
+            [(2**16-1, np.complex64, None),
+             (2**32-1, np.complex128, np.complex64),
+             (np.float16(2), np.complex64, None),
+             (np.float32(2), np.complex64, None),
+             (np.longdouble(2), np.complex64, np.clongdouble),
+             # Base of the double value to sidestep any rounding issues:
+             (np.longdouble(np.nextafter(1.7e308, 0.)),
+                  np.complex128, np.clongdouble),
+             # Additionally use "nextafter" so the cast can't round down:
+             (np.longdouble(np.nextafter(1.7e308, np.inf)),
+                  np.clongdouble, None),
+             # repeat for complex scalars:
+             (np.complex64(2), np.complex64, None),
+             (np.clongdouble(2), np.complex64, np.clongdouble),
+             # Base of the double value to sidestep any rounding issues:
+             (np.clongdouble(np.nextafter(1.7e308, 0.) * 1j),
+                  np.complex128, np.clongdouble),
+             # Additionally use "nextafter" so the cast can't round down:
+             (np.clongdouble(np.nextafter(1.7e308, np.inf)),
+                  np.clongdouble, None),
+             ])
+    def test_complex_other_value_based(self,
+            weak_promotion, other, expected, expected_weak):
+        if weak_promotion and expected_weak is not None:
+            expected = expected_weak
+
+        # This would change if we modify the value based promotion
+        min_complex = np.dtype(np.complex64)
+
+        res = np.result_type(other, min_complex)
+        assert res == expected
+        # Check the same for a simple ufunc call that uses the same logic:
+        res = np.minimum(other, np.ones(3, dtype=min_complex)).dtype
+        assert res == expected
+
+    @pytest.mark.parametrize(["other", "expected"],
+                 [(np.bool_, np.complex128),
+                  (np.int64, np.complex128),
+                  (np.float16, np.complex64),
+                  (np.float32, np.complex64),
+                  (np.float64, np.complex128),
+                  (np.longdouble, np.clongdouble),
+                  (np.complex64, np.complex64),
+                  (np.complex128, np.complex128),
+                  (np.clongdouble, np.clongdouble),
+                  ])
+    def test_complex_scalar_value_based(self, other, expected):
+        # This would change if we modify the value based promotion
+        complex_scalar = 1j
+
+        res = np.result_type(other, complex_scalar)
+        assert res == expected
+        # Check the same for a simple ufunc call that uses the same logic:
+        res = np.minimum(np.ones(3, dtype=other), complex_scalar).dtype
+        assert res == expected
+
+    def test_complex_pyscalar_promote_rational(self):
+        with pytest.raises(TypeError,
+                match=r".* no common DType exists for the given inputs"):
+            np.result_type(1j, rational)
+
+        with pytest.raises(TypeError,
+                match=r".* no common DType exists for the given inputs"):
+            np.result_type(1j, rational(1, 2))
+
+    @pytest.mark.parametrize("val", [2, 2**32, 2**63, 2**64, 2*100])
+    def test_python_integer_promotion(self, val):
+        # If we only path scalars (mainly python ones!), the result must take
+        # into account that the integer may be considered int32, int64, uint64,
+        # or object depending on the input value.  So test those paths!
+        expected_dtype = np.result_type(np.array(val).dtype, np.array(0).dtype)
+        assert np.result_type(val, 0) == expected_dtype
+        # For completeness sake, also check with a NumPy scalar as second arg:
+        assert np.result_type(val, np.int8(0)) == expected_dtype
+
+    @pytest.mark.parametrize(["other", "expected"],
+            [(1, rational), (1., np.float64)])
+    @np._no_nep50_warning()
+    def test_float_int_pyscalar_promote_rational(
+            self, weak_promotion, other, expected):
+        # Note that rationals are a bit akward as they promote with float64
+        # or default ints, but not float16 or uint8/int8 (which looks
+        # inconsistent here).  The new promotion fixes this (partially?)
+        if not weak_promotion and type(other) == float:
+            # The float version, checks float16 in the legacy path, which fails
+            # the integer version seems to check int8 (also), so it can
+            # pass.
+            with pytest.raises(TypeError,
+                    match=r".* do not have a common DType"):
+                np.result_type(other, rational)
+        else:
+            assert np.result_type(other, rational) == expected
+
+        assert np.result_type(other, rational(1, 2)) == expected
+
+    @pytest.mark.parametrize(["dtypes", "expected"], [
+             # These promotions are not associative/commutative:
+             ([np.uint16, np.int16, np.float16], np.float32),
+             ([np.uint16, np.int8, np.float16], np.float32),
+             ([np.uint8, np.int16, np.float16], np.float32),
+             # The following promotions are not ambiguous, but cover code
+             # paths of abstract promotion (no particular logic being tested)
+             ([1, 1, np.float64], np.float64),
+             ([1, 1., np.complex128], np.complex128),
+             ([1, 1j, np.float64], np.complex128),
+             ([1., 1., np.int64], np.float64),
+             ([1., 1j, np.float64], np.complex128),
+             ([1j, 1j, np.float64], np.complex128),
+             ([1, True, np.bool_], np.int_),
+            ])
+    def test_permutations_do_not_influence_result(self, dtypes, expected):
+        # Tests that most permutations do not influence the result.  In the
+        # above some uint and int combintations promote to a larger integer
+        # type, which would then promote to a larger than necessary float.
+        for perm in permutations(dtypes):
+            assert np.result_type(*perm) == expected
+
+
+def test_rational_dtype():
+    # test for bug gh-5719
+    a = np.array([1111], dtype=rational).astype
+    assert_raises(OverflowError, a, 'int8')
+
+    # test that dtype detection finds user-defined types
+    x = rational(1)
+    assert_equal(np.array([x,x]).dtype, np.dtype(rational))
+
+
+def test_dtypes_are_true():
+    # test for gh-6294
+    assert bool(np.dtype('f8'))
+    assert bool(np.dtype('i8'))
+    assert bool(np.dtype([('a', 'i8'), ('b', 'f4')]))
+
+
+def test_invalid_dtype_string():
+    # test for gh-10440
+    assert_raises(TypeError, np.dtype, 'f8,i8,[f8,i8]')
+    assert_raises(TypeError, np.dtype, 'Fl\xfcgel')
+
+
+def test_keyword_argument():
+    # test for https://github.com/numpy/numpy/pull/16574#issuecomment-642660971
+    assert np.dtype(dtype=np.float64) == np.dtype(np.float64)
+
+
+def test_ulong_dtype():
+    # test for gh-21063
+    assert np.dtype("ulong") == np.dtype(np.uint)
+
+
+class TestFromDTypeAttribute:
+    def test_simple(self):
+        class dt:
+            dtype = np.dtype("f8")
+
+        assert np.dtype(dt) == np.float64
+        assert np.dtype(dt()) == np.float64
+
+    @pytest.mark.skipif(IS_PYSTON, reason="Pyston disables recursion checking")
+    def test_recursion(self):
+        class dt:
+            pass
+
+        dt.dtype = dt
+        with pytest.raises(RecursionError):
+            np.dtype(dt)
+
+        dt_instance = dt()
+        dt_instance.dtype = dt
+        with pytest.raises(RecursionError):
+            np.dtype(dt_instance)
+
+    def test_void_subtype(self):
+        class dt(np.void):
+            # This code path is fully untested before, so it is unclear
+            # what this should be useful for. Note that if np.void is used
+            # numpy will think we are deallocating a base type [1.17, 2019-02].
+            dtype = np.dtype("f,f")
+
+        np.dtype(dt)
+        np.dtype(dt(1))
+
+    @pytest.mark.skipif(IS_PYSTON, reason="Pyston disables recursion checking")
+    def test_void_subtype_recursion(self):
+        class vdt(np.void):
+            pass
+
+        vdt.dtype = vdt
+
+        with pytest.raises(RecursionError):
+            np.dtype(vdt)
+
+        with pytest.raises(RecursionError):
+            np.dtype(vdt(1))
+
+
+class TestDTypeClasses:
+    @pytest.mark.parametrize("dtype", list(np.typecodes['All']) + [rational])
+    def test_basic_dtypes_subclass_properties(self, dtype):
+        # Note: Except for the isinstance and type checks, these attributes
+        #       are considered currently private and may change.
+        dtype = np.dtype(dtype)
+        assert isinstance(dtype, np.dtype)
+        assert type(dtype) is not np.dtype
+        if dtype.type.__name__ != "rational":
+            dt_name = type(dtype).__name__.lower().removesuffix("dtype")
+            if dt_name == "uint" or dt_name == "int":
+                # The scalar names has a `c` attached because "int" is Python
+                # int and that is long...
+                dt_name += "c"
+            sc_name = dtype.type.__name__
+            assert dt_name == sc_name.strip("_")
+            assert type(dtype).__module__ == "numpy.dtypes"
+
+            assert getattr(numpy.dtypes, type(dtype).__name__) is type(dtype)
+        else:
+            assert type(dtype).__name__ == "dtype[rational]"
+            assert type(dtype).__module__ == "numpy"
+
+        assert not type(dtype)._abstract
+
+        # the flexible dtypes and datetime/timedelta have additional parameters
+        # which are more than just storage information, these would need to be
+        # given when creating a dtype:
+        parametric = (np.void, np.str_, np.bytes_, np.datetime64, np.timedelta64)
+        if dtype.type not in parametric:
+            assert not type(dtype)._parametric
+            assert type(dtype)() is dtype
+        else:
+            assert type(dtype)._parametric
+            with assert_raises(TypeError):
+                type(dtype)()
+
+    def test_dtype_superclass(self):
+        assert type(np.dtype) is not type
+        assert isinstance(np.dtype, type)
+
+        assert type(np.dtype).__name__ == "_DTypeMeta"
+        assert type(np.dtype).__module__ == "numpy"
+        assert np.dtype._abstract
+
+    def test_is_numeric(self):
+        all_codes = set(np.typecodes['All'])
+        numeric_codes = set(np.typecodes['AllInteger'] +
+                            np.typecodes['AllFloat'] + '?')
+        non_numeric_codes = all_codes - numeric_codes
+
+        for code in numeric_codes:
+            assert type(np.dtype(code))._is_numeric
+
+        for code in non_numeric_codes:
+            assert not type(np.dtype(code))._is_numeric
+
+    @pytest.mark.parametrize("int_", ["UInt", "Int"])
+    @pytest.mark.parametrize("size", [8, 16, 32, 64])
+    def test_integer_alias_names(self, int_, size):
+        DType = getattr(numpy.dtypes, f"{int_}{size}DType")
+        sctype = getattr(numpy, f"{int_.lower()}{size}")
+        assert DType.type is sctype
+        assert DType.__name__.lower().removesuffix("dtype") == sctype.__name__
+
+    @pytest.mark.parametrize("name",
+            ["Half", "Float", "Double", "CFloat", "CDouble"])
+    def test_float_alias_names(self, name):
+        with pytest.raises(AttributeError):
+            getattr(numpy.dtypes, name + "DType") is numpy.dtypes.Float16DType
+
+
+class TestFromCTypes:
+
+    @staticmethod
+    def check(ctype, dtype):
+        dtype = np.dtype(dtype)
+        assert_equal(np.dtype(ctype), dtype)
+        assert_equal(np.dtype(ctype()), dtype)
+
+    def test_array(self):
+        c8 = ctypes.c_uint8
+        self.check(     3 * c8,  (np.uint8, (3,)))
+        self.check(     1 * c8,  (np.uint8, (1,)))
+        self.check(     0 * c8,  (np.uint8, (0,)))
+        self.check(1 * (3 * c8), ((np.uint8, (3,)), (1,)))
+        self.check(3 * (1 * c8), ((np.uint8, (1,)), (3,)))
+
+    def test_padded_structure(self):
+        class PaddedStruct(ctypes.Structure):
+            _fields_ = [
+                ('a', ctypes.c_uint8),
+                ('b', ctypes.c_uint16)
+            ]
+        expected = np.dtype([
+            ('a', np.uint8),
+            ('b', np.uint16)
+        ], align=True)
+        self.check(PaddedStruct, expected)
+
+    def test_bit_fields(self):
+        class BitfieldStruct(ctypes.Structure):
+            _fields_ = [
+                ('a', ctypes.c_uint8, 7),
+                ('b', ctypes.c_uint8, 1)
+            ]
+        assert_raises(TypeError, np.dtype, BitfieldStruct)
+        assert_raises(TypeError, np.dtype, BitfieldStruct())
+
+    def test_pointer(self):
+        p_uint8 = ctypes.POINTER(ctypes.c_uint8)
+        assert_raises(TypeError, np.dtype, p_uint8)
+
+    def test_void_pointer(self):
+        self.check(ctypes.c_void_p, np.uintp)
+
+    def test_union(self):
+        class Union(ctypes.Union):
+            _fields_ = [
+                ('a', ctypes.c_uint8),
+                ('b', ctypes.c_uint16),
+            ]
+        expected = np.dtype(dict(
+            names=['a', 'b'],
+            formats=[np.uint8, np.uint16],
+            offsets=[0, 0],
+            itemsize=2
+        ))
+        self.check(Union, expected)
+
+    def test_union_with_struct_packed(self):
+        class Struct(ctypes.Structure):
+            _pack_ = 1
+            _fields_ = [
+                ('one', ctypes.c_uint8),
+                ('two', ctypes.c_uint32)
+            ]
+
+        class Union(ctypes.Union):
+            _fields_ = [
+                ('a', ctypes.c_uint8),
+                ('b', ctypes.c_uint16),
+                ('c', ctypes.c_uint32),
+                ('d', Struct),
+            ]
+        expected = np.dtype(dict(
+            names=['a', 'b', 'c', 'd'],
+            formats=['u1', np.uint16, np.uint32, [('one', 'u1'), ('two', np.uint32)]],
+            offsets=[0, 0, 0, 0],
+            itemsize=ctypes.sizeof(Union)
+        ))
+        self.check(Union, expected)
+
+    def test_union_packed(self):
+        class Struct(ctypes.Structure):
+            _fields_ = [
+                ('one', ctypes.c_uint8),
+                ('two', ctypes.c_uint32)
+            ]
+            _pack_ = 1
+        class Union(ctypes.Union):
+            _pack_ = 1
+            _fields_ = [
+                ('a', ctypes.c_uint8),
+                ('b', ctypes.c_uint16),
+                ('c', ctypes.c_uint32),
+                ('d', Struct),
+            ]
+        expected = np.dtype(dict(
+            names=['a', 'b', 'c', 'd'],
+            formats=['u1', np.uint16, np.uint32, [('one', 'u1'), ('two', np.uint32)]],
+            offsets=[0, 0, 0, 0],
+            itemsize=ctypes.sizeof(Union)
+        ))
+        self.check(Union, expected)
+
+    def test_packed_structure(self):
+        class PackedStructure(ctypes.Structure):
+            _pack_ = 1
+            _fields_ = [
+                ('a', ctypes.c_uint8),
+                ('b', ctypes.c_uint16)
+            ]
+        expected = np.dtype([
+            ('a', np.uint8),
+            ('b', np.uint16)
+        ])
+        self.check(PackedStructure, expected)
+
+    def test_large_packed_structure(self):
+        class PackedStructure(ctypes.Structure):
+            _pack_ = 2
+            _fields_ = [
+                ('a', ctypes.c_uint8),
+                ('b', ctypes.c_uint16),
+                ('c', ctypes.c_uint8),
+                ('d', ctypes.c_uint16),
+                ('e', ctypes.c_uint32),
+                ('f', ctypes.c_uint32),
+                ('g', ctypes.c_uint8)
+                ]
+        expected = np.dtype(dict(
+            formats=[np.uint8, np.uint16, np.uint8, np.uint16, np.uint32, np.uint32, np.uint8 ],
+            offsets=[0, 2, 4, 6, 8, 12, 16],
+            names=['a', 'b', 'c', 'd', 'e', 'f', 'g'],
+            itemsize=18))
+        self.check(PackedStructure, expected)
+
+    def test_big_endian_structure_packed(self):
+        class BigEndStruct(ctypes.BigEndianStructure):
+            _fields_ = [
+                ('one', ctypes.c_uint8),
+                ('two', ctypes.c_uint32)
+            ]
+            _pack_ = 1
+        expected = np.dtype([('one', 'u1'), ('two', '>u4')])
+        self.check(BigEndStruct, expected)
+
+    def test_little_endian_structure_packed(self):
+        class LittleEndStruct(ctypes.LittleEndianStructure):
+            _fields_ = [
+                ('one', ctypes.c_uint8),
+                ('two', ctypes.c_uint32)
+            ]
+            _pack_ = 1
+        expected = np.dtype([('one', 'u1'), ('two', '<u4')])
+        self.check(LittleEndStruct, expected)
+
+    def test_little_endian_structure(self):
+        class PaddedStruct(ctypes.LittleEndianStructure):
+            _fields_ = [
+                ('a', ctypes.c_uint8),
+                ('b', ctypes.c_uint16)
+            ]
+        expected = np.dtype([
+            ('a', '<B'),
+            ('b', '<H')
+        ], align=True)
+        self.check(PaddedStruct, expected)
+
+    def test_big_endian_structure(self):
+        class PaddedStruct(ctypes.BigEndianStructure):
+            _fields_ = [
+                ('a', ctypes.c_uint8),
+                ('b', ctypes.c_uint16)
+            ]
+        expected = np.dtype([
+            ('a', '>B'),
+            ('b', '>H')
+        ], align=True)
+        self.check(PaddedStruct, expected)
+
+    def test_simple_endian_types(self):
+        self.check(ctypes.c_uint16.__ctype_le__, np.dtype('<u2'))
+        self.check(ctypes.c_uint16.__ctype_be__, np.dtype('>u2'))
+        self.check(ctypes.c_uint8.__ctype_le__, np.dtype('u1'))
+        self.check(ctypes.c_uint8.__ctype_be__, np.dtype('u1'))
+
+    all_types = set(np.typecodes['All'])
+    all_pairs = permutations(all_types, 2)
+
+    @pytest.mark.parametrize("pair", all_pairs)
+    def test_pairs(self, pair):
+        """
+        Check that np.dtype('x,y') matches [np.dtype('x'), np.dtype('y')]
+        Example: np.dtype('d,I') -> dtype([('f0', '<f8'), ('f1', '<u4')])
+        """
+        # gh-5645: check that np.dtype('i,L') can be used
+        pair_type = np.dtype('{},{}'.format(*pair))
+        expected = np.dtype([('f0', pair[0]), ('f1', pair[1])])
+        assert_equal(pair_type, expected)
+
+
+class TestUserDType:
+    @pytest.mark.leaks_references(reason="dynamically creates custom dtype.")
+    def test_custom_structured_dtype(self):
+        class mytype:
+            pass
+
+        blueprint = np.dtype([("field", object)])
+        dt = create_custom_field_dtype(blueprint, mytype, 0)
+        assert dt.type == mytype
+        # We cannot (currently) *create* this dtype with `np.dtype` because
+        # mytype does not inherit from `np.generic`.  This seems like an
+        # unnecessary restriction, but one that has been around forever:
+        assert np.dtype(mytype) == np.dtype("O")
+
+    def test_custom_structured_dtype_errors(self):
+        class mytype:
+            pass
+
+        blueprint = np.dtype([("field", object)])
+
+        with pytest.raises(ValueError):
+            # Tests what happens if fields are unset during creation
+            # which is currently rejected due to the containing object
+            # (see PyArray_RegisterDataType).
+            create_custom_field_dtype(blueprint, mytype, 1)
+
+        with pytest.raises(RuntimeError):
+            # Tests that a dtype must have its type field set up to np.dtype
+            # or in this case a builtin instance.
+            create_custom_field_dtype(blueprint, mytype, 2)
+
+
+class TestClassGetItem:
+    def test_dtype(self) -> None:
+        alias = np.dtype[Any]
+        assert isinstance(alias, types.GenericAlias)
+        assert alias.__origin__ is np.dtype
+
+    @pytest.mark.parametrize("code", np.typecodes["All"])
+    def test_dtype_subclass(self, code: str) -> None:
+        cls = type(np.dtype(code))
+        alias = cls[Any]
+        assert isinstance(alias, types.GenericAlias)
+        assert alias.__origin__ is cls
+
+    @pytest.mark.parametrize("arg_len", range(4))
+    def test_subscript_tuple(self, arg_len: int) -> None:
+        arg_tup = (Any,) * arg_len
+        if arg_len == 1:
+            assert np.dtype[arg_tup]
+        else:
+            with pytest.raises(TypeError):
+                np.dtype[arg_tup]
+
+    def test_subscript_scalar(self) -> None:
+        assert np.dtype[Any]
+
+
+def test_result_type_integers_and_unitless_timedelta64():
+    # Regression test for gh-20077.  The following call of `result_type`
+    # would cause a seg. fault.
+    td = np.timedelta64(4)
+    result = np.result_type(0, td)
+    assert_dtype_equal(result, td.dtype)
+
+
+def test_creating_dtype_with_dtype_class_errors():
+    # Regression test for #25031, calling `np.dtype` with itself segfaulted.
+    with pytest.raises(TypeError, match="Cannot convert np.dtype into a"):
+        np.array(np.ones(10), dtype=np.dtype)

.venv/lib/python3.11/site-packages/numpy/core/tests/test_einsum.py

@@ -0,0 +1,1248 @@
+import itertools
+import sys
+import platform
+
+import pytest
+
+import numpy as np
+from numpy.testing import (
+    assert_, assert_equal, assert_array_equal, assert_almost_equal,
+    assert_raises, suppress_warnings, assert_raises_regex, assert_allclose
+    )
+
+try:
+    COMPILERS = np.show_config(mode="dicts")["Compilers"]
+    USING_CLANG_CL = COMPILERS["c"]["name"] == "clang-cl"
+except TypeError:
+    USING_CLANG_CL = False
+
+# Setup for optimize einsum
+chars = 'abcdefghij'
+sizes = np.array([2, 3, 4, 5, 4, 3, 2, 6, 5, 4, 3])
+global_size_dict = dict(zip(chars, sizes))
+
+
+class TestEinsum:
+    def test_einsum_errors(self):
+        for do_opt in [True, False]:
+            # Need enough arguments
+            assert_raises(ValueError, np.einsum, optimize=do_opt)
+            assert_raises(ValueError, np.einsum, "", optimize=do_opt)
+
+            # subscripts must be a string
+            assert_raises(TypeError, np.einsum, 0, 0, optimize=do_opt)
+
+            # out parameter must be an array
+            assert_raises(TypeError, np.einsum, "", 0, out='test',
+                          optimize=do_opt)
+
+            # order parameter must be a valid order
+            assert_raises(ValueError, np.einsum, "", 0, order='W',
+                          optimize=do_opt)
+
+            # casting parameter must be a valid casting
+            assert_raises(ValueError, np.einsum, "", 0, casting='blah',
+                          optimize=do_opt)
+
+            # dtype parameter must be a valid dtype
+            assert_raises(TypeError, np.einsum, "", 0, dtype='bad_data_type',
+                          optimize=do_opt)
+
+            # other keyword arguments are rejected
+            assert_raises(TypeError, np.einsum, "", 0, bad_arg=0,
+                          optimize=do_opt)
+
+            # issue 4528 revealed a segfault with this call
+            assert_raises(TypeError, np.einsum, *(None,)*63, optimize=do_opt)
+
+            # number of operands must match count in subscripts string
+            assert_raises(ValueError, np.einsum, "", 0, 0, optimize=do_opt)
+            assert_raises(ValueError, np.einsum, ",", 0, [0], [0],
+                          optimize=do_opt)
+            assert_raises(ValueError, np.einsum, ",", [0], optimize=do_opt)
+
+            # can't have more subscripts than dimensions in the operand
+            assert_raises(ValueError, np.einsum, "i", 0, optimize=do_opt)
+            assert_raises(ValueError, np.einsum, "ij", [0, 0], optimize=do_opt)
+            assert_raises(ValueError, np.einsum, "...i", 0, optimize=do_opt)
+            assert_raises(ValueError, np.einsum, "i...j", [0, 0], optimize=do_opt)
+            assert_raises(ValueError, np.einsum, "i...", 0, optimize=do_opt)
+            assert_raises(ValueError, np.einsum, "ij...", [0, 0], optimize=do_opt)
+
+            # invalid ellipsis
+            assert_raises(ValueError, np.einsum, "i..", [0, 0], optimize=do_opt)
+            assert_raises(ValueError, np.einsum, ".i...", [0, 0], optimize=do_opt)
+            assert_raises(ValueError, np.einsum, "j->..j", [0, 0], optimize=do_opt)
+            assert_raises(ValueError, np.einsum, "j->.j...", [0, 0], optimize=do_opt)
+
+            # invalid subscript character
+            assert_raises(ValueError, np.einsum, "i%...", [0, 0], optimize=do_opt)
+            assert_raises(ValueError, np.einsum, "...j$", [0, 0], optimize=do_opt)
+            assert_raises(ValueError, np.einsum, "i->&", [0, 0], optimize=do_opt)
+
+            # output subscripts must appear in input
+            assert_raises(ValueError, np.einsum, "i->ij", [0, 0], optimize=do_opt)
+
+            # output subscripts may only be specified once
+            assert_raises(ValueError, np.einsum, "ij->jij", [[0, 0], [0, 0]],
+                          optimize=do_opt)
+
+            # dimensions much match when being collapsed
+            assert_raises(ValueError, np.einsum, "ii",
+                          np.arange(6).reshape(2, 3), optimize=do_opt)
+            assert_raises(ValueError, np.einsum, "ii->i",
+                          np.arange(6).reshape(2, 3), optimize=do_opt)
+
+            # broadcasting to new dimensions must be enabled explicitly
+            assert_raises(ValueError, np.einsum, "i", np.arange(6).reshape(2, 3),
+                          optimize=do_opt)
+            assert_raises(ValueError, np.einsum, "i->i", [[0, 1], [0, 1]],
+                          out=np.arange(4).reshape(2, 2), optimize=do_opt)
+            with assert_raises_regex(ValueError, "'b'"):
+                # gh-11221 - 'c' erroneously appeared in the error message
+                a = np.ones((3, 3, 4, 5, 6))
+                b = np.ones((3, 4, 5))
+                np.einsum('aabcb,abc', a, b)
+
+            # Check order kwarg, asanyarray allows 1d to pass through
+            assert_raises(ValueError, np.einsum, "i->i", np.arange(6).reshape(-1, 1),
+                          optimize=do_opt, order='d')
+
+    def test_einsum_object_errors(self):
+        # Exceptions created by object arithmetic should
+        # successfully propagate
+
+        class CustomException(Exception):
+            pass
+
+        class DestructoBox:
+
+            def __init__(self, value, destruct):
+                self._val = value
+                self._destruct = destruct
+
+            def __add__(self, other):
+                tmp = self._val + other._val
+                if tmp >= self._destruct:
+                    raise CustomException
+                else:
+                    self._val = tmp
+                    return self
+
+            def __radd__(self, other):
+                if other == 0:
+                    return self
+                else:
+                    return self.__add__(other)
+
+            def __mul__(self, other):
+                tmp = self._val * other._val
+                if tmp >= self._destruct:
+                    raise CustomException
+                else:
+                    self._val = tmp
+                    return self
+
+            def __rmul__(self, other):
+                if other == 0:
+                    return self
+                else:
+                    return self.__mul__(other)
+
+        a = np.array([DestructoBox(i, 5) for i in range(1, 10)],
+                     dtype='object').reshape(3, 3)
+
+        # raised from unbuffered_loop_nop1_ndim2
+        assert_raises(CustomException, np.einsum, "ij->i", a)
+
+        # raised from unbuffered_loop_nop1_ndim3
+        b = np.array([DestructoBox(i, 100) for i in range(0, 27)],
+                     dtype='object').reshape(3, 3, 3)
+        assert_raises(CustomException, np.einsum, "i...k->...", b)
+
+        # raised from unbuffered_loop_nop2_ndim2
+        b = np.array([DestructoBox(i, 55) for i in range(1, 4)],
+                     dtype='object')
+        assert_raises(CustomException, np.einsum, "ij, j", a, b)
+
+        # raised from unbuffered_loop_nop2_ndim3
+        assert_raises(CustomException, np.einsum, "ij, jh", a, a)
+
+        # raised from PyArray_EinsteinSum
+        assert_raises(CustomException, np.einsum, "ij->", a)
+
+    def test_einsum_views(self):
+        # pass-through
+        for do_opt in [True, False]:
+            a = np.arange(6)
+            a.shape = (2, 3)
+
+            b = np.einsum("...", a, optimize=do_opt)
+            assert_(b.base is a)
+
+            b = np.einsum(a, [Ellipsis], optimize=do_opt)
+            assert_(b.base is a)
+
+            b = np.einsum("ij", a, optimize=do_opt)
+            assert_(b.base is a)
+            assert_equal(b, a)
+
+            b = np.einsum(a, [0, 1], optimize=do_opt)
+            assert_(b.base is a)
+            assert_equal(b, a)
+
+            # output is writeable whenever input is writeable
+            b = np.einsum("...", a, optimize=do_opt)
+            assert_(b.flags['WRITEABLE'])
+            a.flags['WRITEABLE'] = False
+            b = np.einsum("...", a, optimize=do_opt)
+            assert_(not b.flags['WRITEABLE'])
+
+            # transpose
+            a = np.arange(6)
+            a.shape = (2, 3)
+
+            b = np.einsum("ji", a, optimize=do_opt)
+            assert_(b.base is a)
+            assert_equal(b, a.T)
+
+            b = np.einsum(a, [1, 0], optimize=do_opt)
+            assert_(b.base is a)
+            assert_equal(b, a.T)
+
+            # diagonal
+            a = np.arange(9)
+            a.shape = (3, 3)
+
+            b = np.einsum("ii->i", a, optimize=do_opt)
+            assert_(b.base is a)
+            assert_equal(b, [a[i, i] for i in range(3)])
+
+            b = np.einsum(a, [0, 0], [0], optimize=do_opt)
+            assert_(b.base is a)
+            assert_equal(b, [a[i, i] for i in range(3)])
+
+            # diagonal with various ways of broadcasting an additional dimension
+            a = np.arange(27)
+            a.shape = (3, 3, 3)
+
+            b = np.einsum("...ii->...i", a, optimize=do_opt)
+            assert_(b.base is a)
+            assert_equal(b, [[x[i, i] for i in range(3)] for x in a])
+
+            b = np.einsum(a, [Ellipsis, 0, 0], [Ellipsis, 0], optimize=do_opt)
+            assert_(b.base is a)
+            assert_equal(b, [[x[i, i] for i in range(3)] for x in a])
+
+            b = np.einsum("ii...->...i", a, optimize=do_opt)
+            assert_(b.base is a)
+            assert_equal(b, [[x[i, i] for i in range(3)]
+                             for x in a.transpose(2, 0, 1)])
+
+            b = np.einsum(a, [0, 0, Ellipsis], [Ellipsis, 0], optimize=do_opt)
+            assert_(b.base is a)
+            assert_equal(b, [[x[i, i] for i in range(3)]
+                             for x in a.transpose(2, 0, 1)])
+
+            b = np.einsum("...ii->i...", a, optimize=do_opt)
+            assert_(b.base is a)
+            assert_equal(b, [a[:, i, i] for i in range(3)])
+
+            b = np.einsum(a, [Ellipsis, 0, 0], [0, Ellipsis], optimize=do_opt)
+            assert_(b.base is a)
+            assert_equal(b, [a[:, i, i] for i in range(3)])
+
+            b = np.einsum("jii->ij", a, optimize=do_opt)
+            assert_(b.base is a)
+            assert_equal(b, [a[:, i, i] for i in range(3)])
+
+            b = np.einsum(a, [1, 0, 0], [0, 1], optimize=do_opt)
+            assert_(b.base is a)
+            assert_equal(b, [a[:, i, i] for i in range(3)])
+
+            b = np.einsum("ii...->i...", a, optimize=do_opt)
+            assert_(b.base is a)
+            assert_equal(b, [a.transpose(2, 0, 1)[:, i, i] for i in range(3)])
+
+            b = np.einsum(a, [0, 0, Ellipsis], [0, Ellipsis], optimize=do_opt)
+            assert_(b.base is a)
+            assert_equal(b, [a.transpose(2, 0, 1)[:, i, i] for i in range(3)])
+
+            b = np.einsum("i...i->i...", a, optimize=do_opt)
+            assert_(b.base is a)
+            assert_equal(b, [a.transpose(1, 0, 2)[:, i, i] for i in range(3)])
+
+            b = np.einsum(a, [0, Ellipsis, 0], [0, Ellipsis], optimize=do_opt)
+            assert_(b.base is a)
+            assert_equal(b, [a.transpose(1, 0, 2)[:, i, i] for i in range(3)])
+
+            b = np.einsum("i...i->...i", a, optimize=do_opt)
+            assert_(b.base is a)
+            assert_equal(b, [[x[i, i] for i in range(3)]
+                             for x in a.transpose(1, 0, 2)])
+
+            b = np.einsum(a, [0, Ellipsis, 0], [Ellipsis, 0], optimize=do_opt)
+            assert_(b.base is a)
+            assert_equal(b, [[x[i, i] for i in range(3)]
+                             for x in a.transpose(1, 0, 2)])
+
+            # triple diagonal
+            a = np.arange(27)
+            a.shape = (3, 3, 3)
+
+            b = np.einsum("iii->i", a, optimize=do_opt)
+            assert_(b.base is a)
+            assert_equal(b, [a[i, i, i] for i in range(3)])
+
+            b = np.einsum(a, [0, 0, 0], [0], optimize=do_opt)
+            assert_(b.base is a)
+            assert_equal(b, [a[i, i, i] for i in range(3)])
+
+            # swap axes
+            a = np.arange(24)
+            a.shape = (2, 3, 4)
+
+            b = np.einsum("ijk->jik", a, optimize=do_opt)
+            assert_(b.base is a)
+            assert_equal(b, a.swapaxes(0, 1))
+
+            b = np.einsum(a, [0, 1, 2], [1, 0, 2], optimize=do_opt)
+            assert_(b.base is a)
+            assert_equal(b, a.swapaxes(0, 1))
+
+    @np._no_nep50_warning()
+    def check_einsum_sums(self, dtype, do_opt=False):
+        dtype = np.dtype(dtype)
+        # Check various sums.  Does many sizes to exercise unrolled loops.
+
+        # sum(a, axis=-1)
+        for n in range(1, 17):
+            a = np.arange(n, dtype=dtype)
+            b = np.sum(a, axis=-1)
+            if hasattr(b, 'astype'):
+                b = b.astype(dtype)
+            assert_equal(np.einsum("i->", a, optimize=do_opt), b)
+            assert_equal(np.einsum(a, [0], [], optimize=do_opt), b)
+
+        for n in range(1, 17):
+            a = np.arange(2*3*n, dtype=dtype).reshape(2, 3, n)
+            b = np.sum(a, axis=-1)
+            if hasattr(b, 'astype'):
+                b = b.astype(dtype)
+            assert_equal(np.einsum("...i->...", a, optimize=do_opt), b)
+            assert_equal(np.einsum(a, [Ellipsis, 0], [Ellipsis], optimize=do_opt), b)
+
+        # sum(a, axis=0)
+        for n in range(1, 17):
+            a = np.arange(2*n, dtype=dtype).reshape(2, n)
+            b = np.sum(a, axis=0)
+            if hasattr(b, 'astype'):
+                b = b.astype(dtype)
+            assert_equal(np.einsum("i...->...", a, optimize=do_opt), b)
+            assert_equal(np.einsum(a, [0, Ellipsis], [Ellipsis], optimize=do_opt), b)
+
+        for n in range(1, 17):
+            a = np.arange(2*3*n, dtype=dtype).reshape(2, 3, n)
+            b = np.sum(a, axis=0)
+            if hasattr(b, 'astype'):
+                b = b.astype(dtype)
+            assert_equal(np.einsum("i...->...", a, optimize=do_opt), b)
+            assert_equal(np.einsum(a, [0, Ellipsis], [Ellipsis], optimize=do_opt), b)
+
+        # trace(a)
+        for n in range(1, 17):
+            a = np.arange(n*n, dtype=dtype).reshape(n, n)
+            b = np.trace(a)
+            if hasattr(b, 'astype'):
+                b = b.astype(dtype)
+            assert_equal(np.einsum("ii", a, optimize=do_opt), b)
+            assert_equal(np.einsum(a, [0, 0], optimize=do_opt), b)
+
+            # gh-15961: should accept numpy int64 type in subscript list
+            np_array = np.asarray([0, 0])
+            assert_equal(np.einsum(a, np_array, optimize=do_opt), b)
+            assert_equal(np.einsum(a, list(np_array), optimize=do_opt), b)
+
+        # multiply(a, b)
+        assert_equal(np.einsum("..., ...", 3, 4), 12)  # scalar case
+        for n in range(1, 17):
+            a = np.arange(3 * n, dtype=dtype).reshape(3, n)
+            b = np.arange(2 * 3 * n, dtype=dtype).reshape(2, 3, n)
+            assert_equal(np.einsum("..., ...", a, b, optimize=do_opt),
+                         np.multiply(a, b))
+            assert_equal(np.einsum(a, [Ellipsis], b, [Ellipsis], optimize=do_opt),
+                         np.multiply(a, b))
+
+        # inner(a,b)
+        for n in range(1, 17):
+            a = np.arange(2 * 3 * n, dtype=dtype).reshape(2, 3, n)
+            b = np.arange(n, dtype=dtype)
+            assert_equal(np.einsum("...i, ...i", a, b, optimize=do_opt), np.inner(a, b))
+            assert_equal(np.einsum(a, [Ellipsis, 0], b, [Ellipsis, 0], optimize=do_opt),
+                         np.inner(a, b))
+
+        for n in range(1, 11):
+            a = np.arange(n * 3 * 2, dtype=dtype).reshape(n, 3, 2)
+            b = np.arange(n, dtype=dtype)
+            assert_equal(np.einsum("i..., i...", a, b, optimize=do_opt),
+                         np.inner(a.T, b.T).T)
+            assert_equal(np.einsum(a, [0, Ellipsis], b, [0, Ellipsis], optimize=do_opt),
+                         np.inner(a.T, b.T).T)
+
+        # outer(a,b)
+        for n in range(1, 17):
+            a = np.arange(3, dtype=dtype)+1
+            b = np.arange(n, dtype=dtype)+1
+            assert_equal(np.einsum("i,j", a, b, optimize=do_opt),
+                         np.outer(a, b))
+            assert_equal(np.einsum(a, [0], b, [1], optimize=do_opt),
+                         np.outer(a, b))
+
+        # Suppress the complex warnings for the 'as f8' tests
+        with suppress_warnings() as sup:
+            sup.filter(np.ComplexWarning)
+
+            # matvec(a,b) / a.dot(b) where a is matrix, b is vector
+            for n in range(1, 17):
+                a = np.arange(4*n, dtype=dtype).reshape(4, n)
+                b = np.arange(n, dtype=dtype)
+                assert_equal(np.einsum("ij, j", a, b, optimize=do_opt),
+                             np.dot(a, b))
+                assert_equal(np.einsum(a, [0, 1], b, [1], optimize=do_opt),
+                             np.dot(a, b))
+
+                c = np.arange(4, dtype=dtype)
+                np.einsum("ij,j", a, b, out=c,
+                          dtype='f8', casting='unsafe', optimize=do_opt)
+                assert_equal(c,
+                             np.dot(a.astype('f8'),
+                                    b.astype('f8')).astype(dtype))
+                c[...] = 0
+                np.einsum(a, [0, 1], b, [1], out=c,
+                          dtype='f8', casting='unsafe', optimize=do_opt)
+                assert_equal(c,
+                             np.dot(a.astype('f8'),
+                                    b.astype('f8')).astype(dtype))
+
+            for n in range(1, 17):
+                a = np.arange(4*n, dtype=dtype).reshape(4, n)
+                b = np.arange(n, dtype=dtype)
+                assert_equal(np.einsum("ji,j", a.T, b.T, optimize=do_opt),
+                             np.dot(b.T, a.T))
+                assert_equal(np.einsum(a.T, [1, 0], b.T, [1], optimize=do_opt),
+                             np.dot(b.T, a.T))
+
+                c = np.arange(4, dtype=dtype)
+                np.einsum("ji,j", a.T, b.T, out=c,
+                          dtype='f8', casting='unsafe', optimize=do_opt)
+                assert_equal(c,
+                             np.dot(b.T.astype('f8'),
+                                    a.T.astype('f8')).astype(dtype))
+                c[...] = 0
+                np.einsum(a.T, [1, 0], b.T, [1], out=c,
+                          dtype='f8', casting='unsafe', optimize=do_opt)
+                assert_equal(c,
+                             np.dot(b.T.astype('f8'),
+                                    a.T.astype('f8')).astype(dtype))
+
+            # matmat(a,b) / a.dot(b) where a is matrix, b is matrix
+            for n in range(1, 17):
+                if n < 8 or dtype != 'f2':
+                    a = np.arange(4*n, dtype=dtype).reshape(4, n)
+                    b = np.arange(n*6, dtype=dtype).reshape(n, 6)
+                    assert_equal(np.einsum("ij,jk", a, b, optimize=do_opt),
+                                 np.dot(a, b))
+                    assert_equal(np.einsum(a, [0, 1], b, [1, 2], optimize=do_opt),
+                                 np.dot(a, b))
+
+            for n in range(1, 17):
+                a = np.arange(4*n, dtype=dtype).reshape(4, n)
+                b = np.arange(n*6, dtype=dtype).reshape(n, 6)
+                c = np.arange(24, dtype=dtype).reshape(4, 6)
+                np.einsum("ij,jk", a, b, out=c, dtype='f8', casting='unsafe',
+                          optimize=do_opt)
+                assert_equal(c,
+                             np.dot(a.astype('f8'),
+                                    b.astype('f8')).astype(dtype))
+                c[...] = 0
+                np.einsum(a, [0, 1], b, [1, 2], out=c,
+                          dtype='f8', casting='unsafe', optimize=do_opt)
+                assert_equal(c,
+                             np.dot(a.astype('f8'),
+                                    b.astype('f8')).astype(dtype))
+
+            # matrix triple product (note this is not currently an efficient
+            # way to multiply 3 matrices)
+            a = np.arange(12, dtype=dtype).reshape(3, 4)
+            b = np.arange(20, dtype=dtype).reshape(4, 5)
+            c = np.arange(30, dtype=dtype).reshape(5, 6)
+            if dtype != 'f2':
+                assert_equal(np.einsum("ij,jk,kl", a, b, c, optimize=do_opt),
+                             a.dot(b).dot(c))
+                assert_equal(np.einsum(a, [0, 1], b, [1, 2], c, [2, 3],
+                                       optimize=do_opt), a.dot(b).dot(c))
+
+            d = np.arange(18, dtype=dtype).reshape(3, 6)
+            np.einsum("ij,jk,kl", a, b, c, out=d,
+                      dtype='f8', casting='unsafe', optimize=do_opt)
+            tgt = a.astype('f8').dot(b.astype('f8'))
+            tgt = tgt.dot(c.astype('f8')).astype(dtype)
+            assert_equal(d, tgt)
+
+            d[...] = 0
+            np.einsum(a, [0, 1], b, [1, 2], c, [2, 3], out=d,
+                      dtype='f8', casting='unsafe', optimize=do_opt)
+            tgt = a.astype('f8').dot(b.astype('f8'))
+            tgt = tgt.dot(c.astype('f8')).astype(dtype)
+            assert_equal(d, tgt)
+
+            # tensordot(a, b)
+            if np.dtype(dtype) != np.dtype('f2'):
+                a = np.arange(60, dtype=dtype).reshape(3, 4, 5)
+                b = np.arange(24, dtype=dtype).reshape(4, 3, 2)
+                assert_equal(np.einsum("ijk, jil -> kl", a, b),
+                             np.tensordot(a, b, axes=([1, 0], [0, 1])))
+                assert_equal(np.einsum(a, [0, 1, 2], b, [1, 0, 3], [2, 3]),
+                             np.tensordot(a, b, axes=([1, 0], [0, 1])))
+
+                c = np.arange(10, dtype=dtype).reshape(5, 2)
+                np.einsum("ijk,jil->kl", a, b, out=c,
+                          dtype='f8', casting='unsafe', optimize=do_opt)
+                assert_equal(c, np.tensordot(a.astype('f8'), b.astype('f8'),
+                             axes=([1, 0], [0, 1])).astype(dtype))
+                c[...] = 0
+                np.einsum(a, [0, 1, 2], b, [1, 0, 3], [2, 3], out=c,
+                          dtype='f8', casting='unsafe', optimize=do_opt)
+                assert_equal(c, np.tensordot(a.astype('f8'), b.astype('f8'),
+                             axes=([1, 0], [0, 1])).astype(dtype))
+
+        # logical_and(logical_and(a!=0, b!=0), c!=0)
+        neg_val = -2 if dtype.kind != "u" else np.iinfo(dtype).max - 1
+        a = np.array([1,   3,   neg_val, 0,  12,  13,   0,   1], dtype=dtype)
+        b = np.array([0,   3.5, 0., neg_val,  0,   1,    3,   12], dtype=dtype)
+        c = np.array([True, True, False, True, True, False, True, True])
+
+        assert_equal(np.einsum("i,i,i->i", a, b, c,
+                     dtype='?', casting='unsafe', optimize=do_opt),
+                     np.logical_and(np.logical_and(a != 0, b != 0), c != 0))
+        assert_equal(np.einsum(a, [0], b, [0], c, [0], [0],
+                     dtype='?', casting='unsafe'),
+                     np.logical_and(np.logical_and(a != 0, b != 0), c != 0))
+
+        a = np.arange(9, dtype=dtype)
+        assert_equal(np.einsum(",i->", 3, a), 3*np.sum(a))
+        assert_equal(np.einsum(3, [], a, [0], []), 3*np.sum(a))
+        assert_equal(np.einsum("i,->", a, 3), 3*np.sum(a))
+        assert_equal(np.einsum(a, [0], 3, [], []), 3*np.sum(a))
+
+        # Various stride0, contiguous, and SSE aligned variants
+        for n in range(1, 25):
+            a = np.arange(n, dtype=dtype)
+            if np.dtype(dtype).itemsize > 1:
+                assert_equal(np.einsum("...,...", a, a, optimize=do_opt),
+                             np.multiply(a, a))
+                assert_equal(np.einsum("i,i", a, a, optimize=do_opt), np.dot(a, a))
+                assert_equal(np.einsum("i,->i", a, 2, optimize=do_opt), 2*a)
+                assert_equal(np.einsum(",i->i", 2, a, optimize=do_opt), 2*a)
+                assert_equal(np.einsum("i,->", a, 2, optimize=do_opt), 2*np.sum(a))
+                assert_equal(np.einsum(",i->", 2, a, optimize=do_opt), 2*np.sum(a))
+
+                assert_equal(np.einsum("...,...", a[1:], a[:-1], optimize=do_opt),
+                             np.multiply(a[1:], a[:-1]))
+                assert_equal(np.einsum("i,i", a[1:], a[:-1], optimize=do_opt),
+                             np.dot(a[1:], a[:-1]))
+                assert_equal(np.einsum("i,->i", a[1:], 2, optimize=do_opt), 2*a[1:])
+                assert_equal(np.einsum(",i->i", 2, a[1:], optimize=do_opt), 2*a[1:])
+                assert_equal(np.einsum("i,->", a[1:], 2, optimize=do_opt),
+                             2*np.sum(a[1:]))
+                assert_equal(np.einsum(",i->", 2, a[1:], optimize=do_opt),
+                             2*np.sum(a[1:]))
+
+        # An object array, summed as the data type
+        a = np.arange(9, dtype=object)
+
+        b = np.einsum("i->", a, dtype=dtype, casting='unsafe')
+        assert_equal(b, np.sum(a))
+        if hasattr(b, "dtype"):
+            # Can be a python object when dtype is object
+            assert_equal(b.dtype, np.dtype(dtype))
+
+        b = np.einsum(a, [0], [], dtype=dtype, casting='unsafe')
+        assert_equal(b, np.sum(a))
+        if hasattr(b, "dtype"):
+            # Can be a python object when dtype is object
+            assert_equal(b.dtype, np.dtype(dtype))
+
+        # A case which was failing (ticket #1885)
+        p = np.arange(2) + 1
+        q = np.arange(4).reshape(2, 2) + 3
+        r = np.arange(4).reshape(2, 2) + 7
+        assert_equal(np.einsum('z,mz,zm->', p, q, r), 253)
+
+        # singleton dimensions broadcast (gh-10343)
+        p = np.ones((10,2))
+        q = np.ones((1,2))
+        assert_array_equal(np.einsum('ij,ij->j', p, q, optimize=True),
+                           np.einsum('ij,ij->j', p, q, optimize=False))
+        assert_array_equal(np.einsum('ij,ij->j', p, q, optimize=True),
+                           [10.] * 2)
+
+        # a blas-compatible contraction broadcasting case which was failing
+        # for optimize=True (ticket #10930)
+        x = np.array([2., 3.])
+        y = np.array([4.])
+        assert_array_equal(np.einsum("i, i", x, y, optimize=False), 20.)
+        assert_array_equal(np.einsum("i, i", x, y, optimize=True), 20.)
+
+        # all-ones array was bypassing bug (ticket #10930)
+        p = np.ones((1, 5)) / 2
+        q = np.ones((5, 5)) / 2
+        for optimize in (True, False):
+            assert_array_equal(np.einsum("...ij,...jk->...ik", p, p,
+                                         optimize=optimize),
+                               np.einsum("...ij,...jk->...ik", p, q,
+                                         optimize=optimize))
+            assert_array_equal(np.einsum("...ij,...jk->...ik", p, q,
+                                         optimize=optimize),
+                               np.full((1, 5), 1.25))
+
+        # Cases which were failing (gh-10899)
+        x = np.eye(2, dtype=dtype)
+        y = np.ones(2, dtype=dtype)
+        assert_array_equal(np.einsum("ji,i->", x, y, optimize=optimize),
+                           [2.])  # contig_contig_outstride0_two
+        assert_array_equal(np.einsum("i,ij->", y, x, optimize=optimize),
+                           [2.])  # stride0_contig_outstride0_two
+        assert_array_equal(np.einsum("ij,i->", x, y, optimize=optimize),
+                           [2.])  # contig_stride0_outstride0_two
+
+    def test_einsum_sums_int8(self):
+        if (
+                (sys.platform == 'darwin' and platform.machine() == 'x86_64')
+                or
+                USING_CLANG_CL
+        ):
+            pytest.xfail('Fails on macOS x86-64 and when using clang-cl '
+                         'with Meson, see gh-23838')
+        self.check_einsum_sums('i1')
+
+    def test_einsum_sums_uint8(self):
+        if (
+                (sys.platform == 'darwin' and platform.machine() == 'x86_64')
+                or
+                USING_CLANG_CL
+        ):
+            pytest.xfail('Fails on macOS x86-64 and when using clang-cl '
+                         'with Meson, see gh-23838')
+        self.check_einsum_sums('u1')
+
+    def test_einsum_sums_int16(self):
+        self.check_einsum_sums('i2')
+
+    def test_einsum_sums_uint16(self):
+        self.check_einsum_sums('u2')
+
+    def test_einsum_sums_int32(self):
+        self.check_einsum_sums('i4')
+        self.check_einsum_sums('i4', True)
+
+    def test_einsum_sums_uint32(self):
+        self.check_einsum_sums('u4')
+        self.check_einsum_sums('u4', True)
+
+    def test_einsum_sums_int64(self):
+        self.check_einsum_sums('i8')
+
+    def test_einsum_sums_uint64(self):
+        self.check_einsum_sums('u8')
+
+    def test_einsum_sums_float16(self):
+        self.check_einsum_sums('f2')
+
+    def test_einsum_sums_float32(self):
+        self.check_einsum_sums('f4')
+
+    def test_einsum_sums_float64(self):
+        self.check_einsum_sums('f8')
+        self.check_einsum_sums('f8', True)
+
+    def test_einsum_sums_longdouble(self):
+        self.check_einsum_sums(np.longdouble)
+
+    def test_einsum_sums_cfloat64(self):
+        self.check_einsum_sums('c8')
+        self.check_einsum_sums('c8', True)
+
+    def test_einsum_sums_cfloat128(self):
+        self.check_einsum_sums('c16')
+
+    def test_einsum_sums_clongdouble(self):
+        self.check_einsum_sums(np.clongdouble)
+
+    def test_einsum_sums_object(self):
+        self.check_einsum_sums('object')
+        self.check_einsum_sums('object', True)
+
+    def test_einsum_misc(self):
+        # This call used to crash because of a bug in
+        # PyArray_AssignZero
+        a = np.ones((1, 2))
+        b = np.ones((2, 2, 1))
+        assert_equal(np.einsum('ij...,j...->i...', a, b), [[[2], [2]]])
+        assert_equal(np.einsum('ij...,j...->i...', a, b, optimize=True), [[[2], [2]]])
+
+        # Regression test for issue #10369 (test unicode inputs with Python 2)
+        assert_equal(np.einsum('ij...,j...->i...', a, b), [[[2], [2]]])
+        assert_equal(np.einsum('...i,...i', [1, 2, 3], [2, 3, 4]), 20)
+        assert_equal(np.einsum('...i,...i', [1, 2, 3], [2, 3, 4],
+                               optimize='greedy'), 20)
+
+        # The iterator had an issue with buffering this reduction
+        a = np.ones((5, 12, 4, 2, 3), np.int64)
+        b = np.ones((5, 12, 11), np.int64)
+        assert_equal(np.einsum('ijklm,ijn,ijn->', a, b, b),
+                     np.einsum('ijklm,ijn->', a, b))
+        assert_equal(np.einsum('ijklm,ijn,ijn->', a, b, b, optimize=True),
+                     np.einsum('ijklm,ijn->', a, b, optimize=True))
+
+        # Issue #2027, was a problem in the contiguous 3-argument
+        # inner loop implementation
+        a = np.arange(1, 3)
+        b = np.arange(1, 5).reshape(2, 2)
+        c = np.arange(1, 9).reshape(4, 2)
+        assert_equal(np.einsum('x,yx,zx->xzy', a, b, c),
+                     [[[1,  3], [3,  9], [5, 15], [7, 21]],
+                     [[8, 16], [16, 32], [24, 48], [32, 64]]])
+        assert_equal(np.einsum('x,yx,zx->xzy', a, b, c, optimize=True),
+                     [[[1,  3], [3,  9], [5, 15], [7, 21]],
+                     [[8, 16], [16, 32], [24, 48], [32, 64]]])
+
+        # Ensure explicitly setting out=None does not cause an error
+        # see issue gh-15776 and issue gh-15256
+        assert_equal(np.einsum('i,j', [1], [2], out=None), [[2]])
+
+    def test_object_loop(self):
+
+        class Mult:
+            def __mul__(self, other):
+                return 42
+
+        objMult = np.array([Mult()])
+        objNULL = np.ndarray(buffer = b'\0' * np.intp(0).itemsize, shape=1, dtype=object)
+
+        with pytest.raises(TypeError):
+            np.einsum("i,j", [1], objNULL)
+        with pytest.raises(TypeError):
+            np.einsum("i,j", objNULL, [1])
+        assert np.einsum("i,j", objMult, objMult) == 42
+
+    def test_subscript_range(self):
+        # Issue #7741, make sure that all letters of Latin alphabet (both uppercase & lowercase) can be used
+        # when creating a subscript from arrays
+        a = np.ones((2, 3))
+        b = np.ones((3, 4))
+        np.einsum(a, [0, 20], b, [20, 2], [0, 2], optimize=False)
+        np.einsum(a, [0, 27], b, [27, 2], [0, 2], optimize=False)
+        np.einsum(a, [0, 51], b, [51, 2], [0, 2], optimize=False)
+        assert_raises(ValueError, lambda: np.einsum(a, [0, 52], b, [52, 2], [0, 2], optimize=False))
+        assert_raises(ValueError, lambda: np.einsum(a, [-1, 5], b, [5, 2], [-1, 2], optimize=False))
+
+    def test_einsum_broadcast(self):
+        # Issue #2455 change in handling ellipsis
+        # remove the 'middle broadcast' error
+        # only use the 'RIGHT' iteration in prepare_op_axes
+        # adds auto broadcast on left where it belongs
+        # broadcast on right has to be explicit
+        # We need to test the optimized parsing as well
+
+        A = np.arange(2 * 3 * 4).reshape(2, 3, 4)
+        B = np.arange(3)
+        ref = np.einsum('ijk,j->ijk', A, B, optimize=False)
+        for opt in [True, False]:
+            assert_equal(np.einsum('ij...,j...->ij...', A, B, optimize=opt), ref)
+            assert_equal(np.einsum('ij...,...j->ij...', A, B, optimize=opt), ref)
+            assert_equal(np.einsum('ij...,j->ij...', A, B, optimize=opt), ref)  # used to raise error
+
+        A = np.arange(12).reshape((4, 3))
+        B = np.arange(6).reshape((3, 2))
+        ref = np.einsum('ik,kj->ij', A, B, optimize=False)
+        for opt in [True, False]:
+            assert_equal(np.einsum('ik...,k...->i...', A, B, optimize=opt), ref)
+            assert_equal(np.einsum('ik...,...kj->i...j', A, B, optimize=opt), ref)
+            assert_equal(np.einsum('...k,kj', A, B, optimize=opt), ref)  # used to raise error
+            assert_equal(np.einsum('ik,k...->i...', A, B, optimize=opt), ref)  # used to raise error
+
+        dims = [2, 3, 4, 5]
+        a = np.arange(np.prod(dims)).reshape(dims)
+        v = np.arange(dims[2])
+        ref = np.einsum('ijkl,k->ijl', a, v, optimize=False)
+        for opt in [True, False]:
+            assert_equal(np.einsum('ijkl,k', a, v, optimize=opt), ref)
+            assert_equal(np.einsum('...kl,k', a, v, optimize=opt), ref)  # used to raise error
+            assert_equal(np.einsum('...kl,k...', a, v, optimize=opt), ref)
+
+        J, K, M = 160, 160, 120
+        A = np.arange(J * K * M).reshape(1, 1, 1, J, K, M)
+        B = np.arange(J * K * M * 3).reshape(J, K, M, 3)
+        ref = np.einsum('...lmn,...lmno->...o', A, B, optimize=False)
+        for opt in [True, False]:
+            assert_equal(np.einsum('...lmn,lmno->...o', A, B,
+                                   optimize=opt), ref)  # used to raise error
+
+    def test_einsum_fixedstridebug(self):
+        # Issue #4485 obscure einsum bug
+        # This case revealed a bug in nditer where it reported a stride
+        # as 'fixed' (0) when it was in fact not fixed during processing
+        # (0 or 4). The reason for the bug was that the check for a fixed
+        # stride was using the information from the 2D inner loop reuse
+        # to restrict the iteration dimensions it had to validate to be
+        # the same, but that 2D inner loop reuse logic is only triggered
+        # during the buffer copying step, and hence it was invalid to
+        # rely on those values. The fix is to check all the dimensions
+        # of the stride in question, which in the test case reveals that
+        # the stride is not fixed.
+        #
+        # NOTE: This test is triggered by the fact that the default buffersize,
+        #       used by einsum, is 8192, and 3*2731 = 8193, is larger than that
+        #       and results in a mismatch between the buffering and the
+        #       striding for operand A.
+        A = np.arange(2 * 3).reshape(2, 3).astype(np.float32)
+        B = np.arange(2 * 3 * 2731).reshape(2, 3, 2731).astype(np.int16)
+        es = np.einsum('cl, cpx->lpx',  A,  B)
+        tp = np.tensordot(A,  B,  axes=(0,  0))
+        assert_equal(es,  tp)
+        # The following is the original test case from the bug report,
+        # made repeatable by changing random arrays to aranges.
+        A = np.arange(3 * 3).reshape(3, 3).astype(np.float64)
+        B = np.arange(3 * 3 * 64 * 64).reshape(3, 3, 64, 64).astype(np.float32)
+        es = np.einsum('cl, cpxy->lpxy',  A, B)
+        tp = np.tensordot(A, B,  axes=(0, 0))
+        assert_equal(es, tp)
+
+    def test_einsum_fixed_collapsingbug(self):
+        # Issue #5147.
+        # The bug only occurred when output argument of einssum was used.
+        x = np.random.normal(0, 1, (5, 5, 5, 5))
+        y1 = np.zeros((5, 5))
+        np.einsum('aabb->ab', x, out=y1)
+        idx = np.arange(5)
+        y2 = x[idx[:, None], idx[:, None], idx, idx]
+        assert_equal(y1, y2)
+
+    def test_einsum_failed_on_p9_and_s390x(self):
+        # Issues gh-14692 and gh-12689
+        # Bug with signed vs unsigned char errored on power9 and s390x Linux
+        tensor = np.random.random_sample((10, 10, 10, 10))
+        x = np.einsum('ijij->', tensor)
+        y = tensor.trace(axis1=0, axis2=2).trace()
+        assert_allclose(x, y)
+
+    def test_einsum_all_contig_non_contig_output(self):
+        # Issue gh-5907, tests that the all contiguous special case
+        # actually checks the contiguity of the output
+        x = np.ones((5, 5))
+        out = np.ones(10)[::2]
+        correct_base = np.ones(10)
+        correct_base[::2] = 5
+        # Always worked (inner iteration is done with 0-stride):
+        np.einsum('mi,mi,mi->m', x, x, x, out=out)
+        assert_array_equal(out.base, correct_base)
+        # Example 1:
+        out = np.ones(10)[::2]
+        np.einsum('im,im,im->m', x, x, x, out=out)
+        assert_array_equal(out.base, correct_base)
+        # Example 2, buffering causes x to be contiguous but
+        # special cases do not catch the operation before:
+        out = np.ones((2, 2, 2))[..., 0]
+        correct_base = np.ones((2, 2, 2))
+        correct_base[..., 0] = 2
+        x = np.ones((2, 2), np.float32)
+        np.einsum('ij,jk->ik', x, x, out=out)
+        assert_array_equal(out.base, correct_base)
+
+    @pytest.mark.parametrize("dtype",
+             np.typecodes["AllFloat"] + np.typecodes["AllInteger"])
+    def test_different_paths(self, dtype):
+        # Test originally added to cover broken float16 path: gh-20305
+        # Likely most are covered elsewhere, at least partially.
+        dtype = np.dtype(dtype)
+        # Simple test, designed to exercise most specialized code paths,
+        # note the +0.5 for floats.  This makes sure we use a float value
+        # where the results must be exact.
+        arr = (np.arange(7) + 0.5).astype(dtype)
+        scalar = np.array(2, dtype=dtype)
+
+        # contig -> scalar:
+        res = np.einsum('i->', arr)
+        assert res == arr.sum()
+        # contig, contig -> contig:
+        res = np.einsum('i,i->i', arr, arr)
+        assert_array_equal(res, arr * arr)
+        # noncontig, noncontig -> contig:
+        res = np.einsum('i,i->i', arr.repeat(2)[::2], arr.repeat(2)[::2])
+        assert_array_equal(res, arr * arr)
+        # contig + contig -> scalar
+        assert np.einsum('i,i->', arr, arr) == (arr * arr).sum()
+        # contig + scalar -> contig (with out)
+        out = np.ones(7, dtype=dtype)
+        res = np.einsum('i,->i', arr, dtype.type(2), out=out)
+        assert_array_equal(res, arr * dtype.type(2))
+        # scalar + contig -> contig (with out)
+        res = np.einsum(',i->i', scalar, arr)
+        assert_array_equal(res, arr * dtype.type(2))
+        # scalar + contig -> scalar
+        res = np.einsum(',i->', scalar, arr)
+        # Use einsum to compare to not have difference due to sum round-offs:
+        assert res == np.einsum('i->', scalar * arr)
+        # contig + scalar -> scalar
+        res = np.einsum('i,->', arr, scalar)
+        # Use einsum to compare to not have difference due to sum round-offs:
+        assert res == np.einsum('i->', scalar * arr)
+        # contig + contig + contig -> scalar
+        arr = np.array([0.5, 0.5, 0.25, 4.5, 3.], dtype=dtype)
+        res = np.einsum('i,i,i->', arr, arr, arr)
+        assert_array_equal(res, (arr * arr * arr).sum())
+        # four arrays:
+        res = np.einsum('i,i,i,i->', arr, arr, arr, arr)
+        assert_array_equal(res, (arr * arr * arr * arr).sum())
+
+    def test_small_boolean_arrays(self):
+        # See gh-5946.
+        # Use array of True embedded in False.
+        a = np.zeros((16, 1, 1), dtype=np.bool_)[:2]
+        a[...] = True
+        out = np.zeros((16, 1, 1), dtype=np.bool_)[:2]
+        tgt = np.ones((2, 1, 1), dtype=np.bool_)
+        res = np.einsum('...ij,...jk->...ik', a, a, out=out)
+        assert_equal(res, tgt)
+
+    def test_out_is_res(self):
+        a = np.arange(9).reshape(3, 3)
+        res = np.einsum('...ij,...jk->...ik', a, a, out=a)
+        assert res is a
+
+    def optimize_compare(self, subscripts, operands=None):
+        # Tests all paths of the optimization function against
+        # conventional einsum
+        if operands is None:
+            args = [subscripts]
+            terms = subscripts.split('->')[0].split(',')
+            for term in terms:
+                dims = [global_size_dict[x] for x in term]
+                args.append(np.random.rand(*dims))
+        else:
+            args = [subscripts] + operands
+
+        noopt = np.einsum(*args, optimize=False)
+        opt = np.einsum(*args, optimize='greedy')
+        assert_almost_equal(opt, noopt)
+        opt = np.einsum(*args, optimize='optimal')
+        assert_almost_equal(opt, noopt)
+
+    def test_hadamard_like_products(self):
+        # Hadamard outer products
+        self.optimize_compare('a,ab,abc->abc')
+        self.optimize_compare('a,b,ab->ab')
+
+    def test_index_transformations(self):
+        # Simple index transformation cases
+        self.optimize_compare('ea,fb,gc,hd,abcd->efgh')
+        self.optimize_compare('ea,fb,abcd,gc,hd->efgh')
+        self.optimize_compare('abcd,ea,fb,gc,hd->efgh')
+
+    def test_complex(self):
+        # Long test cases
+        self.optimize_compare('acdf,jbje,gihb,hfac,gfac,gifabc,hfac')
+        self.optimize_compare('acdf,jbje,gihb,hfac,gfac,gifabc,hfac')
+        self.optimize_compare('cd,bdhe,aidb,hgca,gc,hgibcd,hgac')
+        self.optimize_compare('abhe,hidj,jgba,hiab,gab')
+        self.optimize_compare('bde,cdh,agdb,hica,ibd,hgicd,hiac')
+        self.optimize_compare('chd,bde,agbc,hiad,hgc,hgi,hiad')
+        self.optimize_compare('chd,bde,agbc,hiad,bdi,cgh,agdb')
+        self.optimize_compare('bdhe,acad,hiab,agac,hibd')
+
+    def test_collapse(self):
+        # Inner products
+        self.optimize_compare('ab,ab,c->')
+        self.optimize_compare('ab,ab,c->c')
+        self.optimize_compare('ab,ab,cd,cd->')
+        self.optimize_compare('ab,ab,cd,cd->ac')
+        self.optimize_compare('ab,ab,cd,cd->cd')
+        self.optimize_compare('ab,ab,cd,cd,ef,ef->')
+
+    def test_expand(self):
+        # Outer products
+        self.optimize_compare('ab,cd,ef->abcdef')
+        self.optimize_compare('ab,cd,ef->acdf')
+        self.optimize_compare('ab,cd,de->abcde')
+        self.optimize_compare('ab,cd,de->be')
+        self.optimize_compare('ab,bcd,cd->abcd')
+        self.optimize_compare('ab,bcd,cd->abd')
+
+    def test_edge_cases(self):
+        # Difficult edge cases for optimization
+        self.optimize_compare('eb,cb,fb->cef')
+        self.optimize_compare('dd,fb,be,cdb->cef')
+        self.optimize_compare('bca,cdb,dbf,afc->')
+        self.optimize_compare('dcc,fce,ea,dbf->ab')
+        self.optimize_compare('fdf,cdd,ccd,afe->ae')
+        self.optimize_compare('abcd,ad')
+        self.optimize_compare('ed,fcd,ff,bcf->be')
+        self.optimize_compare('baa,dcf,af,cde->be')
+        self.optimize_compare('bd,db,eac->ace')
+        self.optimize_compare('fff,fae,bef,def->abd')
+        self.optimize_compare('efc,dbc,acf,fd->abe')
+        self.optimize_compare('ba,ac,da->bcd')
+
+    def test_inner_product(self):
+        # Inner products
+        self.optimize_compare('ab,ab')
+        self.optimize_compare('ab,ba')
+        self.optimize_compare('abc,abc')
+        self.optimize_compare('abc,bac')
+        self.optimize_compare('abc,cba')
+
+    def test_random_cases(self):
+        # Randomly built test cases
+        self.optimize_compare('aab,fa,df,ecc->bde')
+        self.optimize_compare('ecb,fef,bad,ed->ac')
+        self.optimize_compare('bcf,bbb,fbf,fc->')
+        self.optimize_compare('bb,ff,be->e')
+        self.optimize_compare('bcb,bb,fc,fff->')
+        self.optimize_compare('fbb,dfd,fc,fc->')
+        self.optimize_compare('afd,ba,cc,dc->bf')
+        self.optimize_compare('adb,bc,fa,cfc->d')
+        self.optimize_compare('bbd,bda,fc,db->acf')
+        self.optimize_compare('dba,ead,cad->bce')
+        self.optimize_compare('aef,fbc,dca->bde')
+
+    def test_combined_views_mapping(self):
+        # gh-10792
+        a = np.arange(9).reshape(1, 1, 3, 1, 3)
+        b = np.einsum('bbcdc->d', a)
+        assert_equal(b, [12])
+
+    def test_broadcasting_dot_cases(self):
+        # Ensures broadcasting cases are not mistaken for GEMM
+
+        a = np.random.rand(1, 5, 4)
+        b = np.random.rand(4, 6)
+        c = np.random.rand(5, 6)
+        d = np.random.rand(10)
+
+        self.optimize_compare('ijk,kl,jl', operands=[a, b, c])
+        self.optimize_compare('ijk,kl,jl,i->i', operands=[a, b, c, d])
+
+        e = np.random.rand(1, 1, 5, 4)
+        f = np.random.rand(7, 7)
+        self.optimize_compare('abjk,kl,jl', operands=[e, b, c])
+        self.optimize_compare('abjk,kl,jl,ab->ab', operands=[e, b, c, f])
+
+        # Edge case found in gh-11308
+        g = np.arange(64).reshape(2, 4, 8)
+        self.optimize_compare('obk,ijk->ioj', operands=[g, g])
+
+    def test_output_order(self):
+        # Ensure output order is respected for optimize cases, the below
+        # conraction should yield a reshaped tensor view
+        # gh-16415
+
+        a = np.ones((2, 3, 5), order='F')
+        b = np.ones((4, 3), order='F')
+
+        for opt in [True, False]:
+            tmp = np.einsum('...ft,mf->...mt', a, b, order='a', optimize=opt)
+            assert_(tmp.flags.f_contiguous)
+
+            tmp = np.einsum('...ft,mf->...mt', a, b, order='f', optimize=opt)
+            assert_(tmp.flags.f_contiguous)
+
+            tmp = np.einsum('...ft,mf->...mt', a, b, order='c', optimize=opt)
+            assert_(tmp.flags.c_contiguous)
+
+            tmp = np.einsum('...ft,mf->...mt', a, b, order='k', optimize=opt)
+            assert_(tmp.flags.c_contiguous is False)
+            assert_(tmp.flags.f_contiguous is False)
+
+            tmp = np.einsum('...ft,mf->...mt', a, b, optimize=opt)
+            assert_(tmp.flags.c_contiguous is False)
+            assert_(tmp.flags.f_contiguous is False)
+
+        c = np.ones((4, 3), order='C')
+        for opt in [True, False]:
+            tmp = np.einsum('...ft,mf->...mt', a, c, order='a', optimize=opt)
+            assert_(tmp.flags.c_contiguous)
+
+        d = np.ones((2, 3, 5), order='C')
+        for opt in [True, False]:
+            tmp = np.einsum('...ft,mf->...mt', d, c, order='a', optimize=opt)
+            assert_(tmp.flags.c_contiguous)
+
+class TestEinsumPath:
+    def build_operands(self, string, size_dict=global_size_dict):
+
+        # Builds views based off initial operands
+        operands = [string]
+        terms = string.split('->')[0].split(',')
+        for term in terms:
+            dims = [size_dict[x] for x in term]
+            operands.append(np.random.rand(*dims))
+
+        return operands
+
+    def assert_path_equal(self, comp, benchmark):
+        # Checks if list of tuples are equivalent
+        ret = (len(comp) == len(benchmark))
+        assert_(ret)
+        for pos in range(len(comp) - 1):
+            ret &= isinstance(comp[pos + 1], tuple)
+            ret &= (comp[pos + 1] == benchmark[pos + 1])
+        assert_(ret)
+
+    def test_memory_contraints(self):
+        # Ensure memory constraints are satisfied
+
+        outer_test = self.build_operands('a,b,c->abc')
+
+        path, path_str = np.einsum_path(*outer_test, optimize=('greedy', 0))
+        self.assert_path_equal(path, ['einsum_path', (0, 1, 2)])
+
+        path, path_str = np.einsum_path(*outer_test, optimize=('optimal', 0))
+        self.assert_path_equal(path, ['einsum_path', (0, 1, 2)])
+
+        long_test = self.build_operands('acdf,jbje,gihb,hfac')
+        path, path_str = np.einsum_path(*long_test, optimize=('greedy', 0))
+        self.assert_path_equal(path, ['einsum_path', (0, 1, 2, 3)])
+
+        path, path_str = np.einsum_path(*long_test, optimize=('optimal', 0))
+        self.assert_path_equal(path, ['einsum_path', (0, 1, 2, 3)])
+
+    def test_long_paths(self):
+        # Long complex cases
+
+        # Long test 1
+        long_test1 = self.build_operands('acdf,jbje,gihb,hfac,gfac,gifabc,hfac')
+        path, path_str = np.einsum_path(*long_test1, optimize='greedy')
+        self.assert_path_equal(path, ['einsum_path',
+                                      (3, 6), (3, 4), (2, 4), (2, 3), (0, 2), (0, 1)])
+
+        path, path_str = np.einsum_path(*long_test1, optimize='optimal')
+        self.assert_path_equal(path, ['einsum_path',
+                                      (3, 6), (3, 4), (2, 4), (2, 3), (0, 2), (0, 1)])
+
+        # Long test 2
+        long_test2 = self.build_operands('chd,bde,agbc,hiad,bdi,cgh,agdb')
+        path, path_str = np.einsum_path(*long_test2, optimize='greedy')
+        self.assert_path_equal(path, ['einsum_path',
+                                      (3, 4), (0, 3), (3, 4), (1, 3), (1, 2), (0, 1)])
+
+        path, path_str = np.einsum_path(*long_test2, optimize='optimal')
+        self.assert_path_equal(path, ['einsum_path',
+                                      (0, 5), (1, 4), (3, 4), (1, 3), (1, 2), (0, 1)])
+
+    def test_edge_paths(self):
+        # Difficult edge cases
+
+        # Edge test1
+        edge_test1 = self.build_operands('eb,cb,fb->cef')
+        path, path_str = np.einsum_path(*edge_test1, optimize='greedy')
+        self.assert_path_equal(path, ['einsum_path', (0, 2), (0, 1)])
+
+        path, path_str = np.einsum_path(*edge_test1, optimize='optimal')
+        self.assert_path_equal(path, ['einsum_path', (0, 2), (0, 1)])
+
+        # Edge test2
+        edge_test2 = self.build_operands('dd,fb,be,cdb->cef')
+        path, path_str = np.einsum_path(*edge_test2, optimize='greedy')
+        self.assert_path_equal(path, ['einsum_path', (0, 3), (0, 1), (0, 1)])
+
+        path, path_str = np.einsum_path(*edge_test2, optimize='optimal')
+        self.assert_path_equal(path, ['einsum_path', (0, 3), (0, 1), (0, 1)])
+
+        # Edge test3
+        edge_test3 = self.build_operands('bca,cdb,dbf,afc->')
+        path, path_str = np.einsum_path(*edge_test3, optimize='greedy')
+        self.assert_path_equal(path, ['einsum_path', (1, 2), (0, 2), (0, 1)])
+
+        path, path_str = np.einsum_path(*edge_test3, optimize='optimal')
+        self.assert_path_equal(path, ['einsum_path', (1, 2), (0, 2), (0, 1)])
+
+        # Edge test4
+        edge_test4 = self.build_operands('dcc,fce,ea,dbf->ab')
+        path, path_str = np.einsum_path(*edge_test4, optimize='greedy')
+        self.assert_path_equal(path, ['einsum_path', (1, 2), (0, 1), (0, 1)])
+
+        path, path_str = np.einsum_path(*edge_test4, optimize='optimal')
+        self.assert_path_equal(path, ['einsum_path', (1, 2), (0, 2), (0, 1)])
+
+        # Edge test5
+        edge_test4 = self.build_operands('a,ac,ab,ad,cd,bd,bc->',
+                                         size_dict={"a": 20, "b": 20, "c": 20, "d": 20})
+        path, path_str = np.einsum_path(*edge_test4, optimize='greedy')
+        self.assert_path_equal(path, ['einsum_path', (0, 1), (0, 1, 2, 3, 4, 5)])
+
+        path, path_str = np.einsum_path(*edge_test4, optimize='optimal')
+        self.assert_path_equal(path, ['einsum_path', (0, 1), (0, 1, 2, 3, 4, 5)])
+
+    def test_path_type_input(self):
+        # Test explicit path handling
+        path_test = self.build_operands('dcc,fce,ea,dbf->ab')
+
+        path, path_str = np.einsum_path(*path_test, optimize=False)
+        self.assert_path_equal(path, ['einsum_path', (0, 1, 2, 3)])
+
+        path, path_str = np.einsum_path(*path_test, optimize=True)
+        self.assert_path_equal(path, ['einsum_path', (1, 2), (0, 1), (0, 1)])
+
+        exp_path = ['einsum_path', (0, 2), (0, 2), (0, 1)]
+        path, path_str = np.einsum_path(*path_test, optimize=exp_path)
+        self.assert_path_equal(path, exp_path)
+
+        # Double check einsum works on the input path
+        noopt = np.einsum(*path_test, optimize=False)
+        opt = np.einsum(*path_test, optimize=exp_path)
+        assert_almost_equal(noopt, opt)
+
+    def test_path_type_input_internal_trace(self):
+        #gh-20962
+        path_test = self.build_operands('cab,cdd->ab')
+        exp_path = ['einsum_path', (1,), (0, 1)]
+
+        path, path_str = np.einsum_path(*path_test, optimize=exp_path)
+        self.assert_path_equal(path, exp_path)
+
+        # Double check einsum works on the input path
+        noopt = np.einsum(*path_test, optimize=False)
+        opt = np.einsum(*path_test, optimize=exp_path)
+        assert_almost_equal(noopt, opt)
+
+    def test_path_type_input_invalid(self):
+        path_test = self.build_operands('ab,bc,cd,de->ae')
+        exp_path = ['einsum_path', (2, 3), (0, 1)]
+        assert_raises(RuntimeError, np.einsum, *path_test, optimize=exp_path)
+        assert_raises(
+            RuntimeError, np.einsum_path, *path_test, optimize=exp_path)
+
+        path_test = self.build_operands('a,a,a->a')
+        exp_path = ['einsum_path', (1,), (0, 1)]
+        assert_raises(RuntimeError, np.einsum, *path_test, optimize=exp_path)
+        assert_raises(
+            RuntimeError, np.einsum_path, *path_test, optimize=exp_path)
+
+    def test_spaces(self):
+        #gh-10794
+        arr = np.array([[1]])
+        for sp in itertools.product(['', ' '], repeat=4):
+            # no error for any spacing
+            np.einsum('{}...a{}->{}...a{}'.format(*sp), arr)
+
+def test_overlap():
+    a = np.arange(9, dtype=int).reshape(3, 3)
+    b = np.arange(9, dtype=int).reshape(3, 3)
+    d = np.dot(a, b)
+    # sanity check
+    c = np.einsum('ij,jk->ik', a, b)
+    assert_equal(c, d)
+    #gh-10080, out overlaps one of the operands
+    c = np.einsum('ij,jk->ik', a, b, out=b)
+    assert_equal(c, d)

.venv/lib/python3.11/site-packages/numpy/core/tests/test_errstate.py

@@ -0,0 +1,61 @@
+import pytest
+import sysconfig
+
+import numpy as np
+from numpy.testing import assert_, assert_raises, IS_WASM
+
+# The floating point emulation on ARM EABI systems lacking a hardware FPU is
+# known to be buggy. This is an attempt to identify these hosts. It may not
+# catch all possible cases, but it catches the known cases of gh-413 and
+# gh-15562.
+hosttype = sysconfig.get_config_var('HOST_GNU_TYPE')
+arm_softfloat = False if hosttype is None else hosttype.endswith('gnueabi')
+
+class TestErrstate:
+    @pytest.mark.skipif(IS_WASM, reason="fp errors don't work in wasm")
+    @pytest.mark.skipif(arm_softfloat,
+                        reason='platform/cpu issue with FPU (gh-413,-15562)')
+    def test_invalid(self):
+        with np.errstate(all='raise', under='ignore'):
+            a = -np.arange(3)
+            # This should work
+            with np.errstate(invalid='ignore'):
+                np.sqrt(a)
+            # While this should fail!
+            with assert_raises(FloatingPointError):
+                np.sqrt(a)
+
+    @pytest.mark.skipif(IS_WASM, reason="fp errors don't work in wasm")
+    @pytest.mark.skipif(arm_softfloat,
+                        reason='platform/cpu issue with FPU (gh-15562)')
+    def test_divide(self):
+        with np.errstate(all='raise', under='ignore'):
+            a = -np.arange(3)
+            # This should work
+            with np.errstate(divide='ignore'):
+                a // 0
+            # While this should fail!
+            with assert_raises(FloatingPointError):
+                a // 0
+            # As should this, see gh-15562
+            with assert_raises(FloatingPointError):
+                a // a
+
+    def test_errcall(self):
+        def foo(*args):
+            print(args)
+
+        olderrcall = np.geterrcall()
+        with np.errstate(call=foo):
+            assert_(np.geterrcall() is foo, 'call is not foo')
+            with np.errstate(call=None):
+                assert_(np.geterrcall() is None, 'call is not None')
+        assert_(np.geterrcall() is olderrcall, 'call is not olderrcall')
+
+    def test_errstate_decorator(self):
+        @np.errstate(all='ignore')
+        def foo():
+            a = -np.arange(3)
+            a // 0
+            
+        foo()

.venv/lib/python3.11/site-packages/numpy/core/tests/test_function_base.py

@@ -0,0 +1,446 @@
+import pytest
+from numpy import (
+    logspace, linspace, geomspace, dtype, array, sctypes, arange, isnan,
+    ndarray, sqrt, nextafter, stack, errstate
+    )
+from numpy.testing import (
+    assert_, assert_equal, assert_raises, assert_array_equal, assert_allclose,
+    )
+
+
+class PhysicalQuantity(float):
+    def __new__(cls, value):
+        return float.__new__(cls, value)
+
+    def __add__(self, x):
+        assert_(isinstance(x, PhysicalQuantity))
+        return PhysicalQuantity(float(x) + float(self))
+    __radd__ = __add__
+
+    def __sub__(self, x):
+        assert_(isinstance(x, PhysicalQuantity))
+        return PhysicalQuantity(float(self) - float(x))
+
+    def __rsub__(self, x):
+        assert_(isinstance(x, PhysicalQuantity))
+        return PhysicalQuantity(float(x) - float(self))
+
+    def __mul__(self, x):
+        return PhysicalQuantity(float(x) * float(self))
+    __rmul__ = __mul__
+
+    def __div__(self, x):
+        return PhysicalQuantity(float(self) / float(x))
+
+    def __rdiv__(self, x):
+        return PhysicalQuantity(float(x) / float(self))
+
+
+class PhysicalQuantity2(ndarray):
+    __array_priority__ = 10
+
+
+class TestLogspace:
+
+    def test_basic(self):
+        y = logspace(0, 6)
+        assert_(len(y) == 50)
+        y = logspace(0, 6, num=100)
+        assert_(y[-1] == 10 ** 6)
+        y = logspace(0, 6, endpoint=False)
+        assert_(y[-1] < 10 ** 6)
+        y = logspace(0, 6, num=7)
+        assert_array_equal(y, [1, 10, 100, 1e3, 1e4, 1e5, 1e6])
+
+    def test_start_stop_array(self):
+        start = array([0., 1.])
+        stop = array([6., 7.])
+        t1 = logspace(start, stop, 6)
+        t2 = stack([logspace(_start, _stop, 6)
+                    for _start, _stop in zip(start, stop)], axis=1)
+        assert_equal(t1, t2)
+        t3 = logspace(start, stop[0], 6)
+        t4 = stack([logspace(_start, stop[0], 6)
+                    for _start in start], axis=1)
+        assert_equal(t3, t4)
+        t5 = logspace(start, stop, 6, axis=-1)
+        assert_equal(t5, t2.T)
+
+    @pytest.mark.parametrize("axis", [0, 1, -1])
+    def test_base_array(self, axis: int):
+        start = 1
+        stop = 2
+        num = 6
+        base = array([1, 2])
+        t1 = logspace(start, stop, num=num, base=base, axis=axis)
+        t2 = stack(
+            [logspace(start, stop, num=num, base=_base) for _base in base],
+            axis=(axis + 1) % t1.ndim,
+        )
+        assert_equal(t1, t2)
+
+    @pytest.mark.parametrize("axis", [0, 1, -1])
+    def test_stop_base_array(self, axis: int):
+        start = 1
+        stop = array([2, 3])
+        num = 6
+        base = array([1, 2])
+        t1 = logspace(start, stop, num=num, base=base, axis=axis)
+        t2 = stack(
+            [logspace(start, _stop, num=num, base=_base)
+             for _stop, _base in zip(stop, base)],
+            axis=(axis + 1) % t1.ndim,
+        )
+        assert_equal(t1, t2)
+
+    def test_dtype(self):
+        y = logspace(0, 6, dtype='float32')
+        assert_equal(y.dtype, dtype('float32'))
+        y = logspace(0, 6, dtype='float64')
+        assert_equal(y.dtype, dtype('float64'))
+        y = logspace(0, 6, dtype='int32')
+        assert_equal(y.dtype, dtype('int32'))
+
+    def test_physical_quantities(self):
+        a = PhysicalQuantity(1.0)
+        b = PhysicalQuantity(5.0)
+        assert_equal(logspace(a, b), logspace(1.0, 5.0))
+
+    def test_subclass(self):
+        a = array(1).view(PhysicalQuantity2)
+        b = array(7).view(PhysicalQuantity2)
+        ls = logspace(a, b)
+        assert type(ls) is PhysicalQuantity2
+        assert_equal(ls, logspace(1.0, 7.0))
+        ls = logspace(a, b, 1)
+        assert type(ls) is PhysicalQuantity2
+        assert_equal(ls, logspace(1.0, 7.0, 1))
+
+
+class TestGeomspace:
+
+    def test_basic(self):
+        y = geomspace(1, 1e6)
+        assert_(len(y) == 50)
+        y = geomspace(1, 1e6, num=100)
+        assert_(y[-1] == 10 ** 6)
+        y = geomspace(1, 1e6, endpoint=False)
+        assert_(y[-1] < 10 ** 6)
+        y = geomspace(1, 1e6, num=7)
+        assert_array_equal(y, [1, 10, 100, 1e3, 1e4, 1e5, 1e6])
+
+        y = geomspace(8, 2, num=3)
+        assert_allclose(y, [8, 4, 2])
+        assert_array_equal(y.imag, 0)
+
+        y = geomspace(-1, -100, num=3)
+        assert_array_equal(y, [-1, -10, -100])
+        assert_array_equal(y.imag, 0)
+
+        y = geomspace(-100, -1, num=3)
+        assert_array_equal(y, [-100, -10, -1])
+        assert_array_equal(y.imag, 0)
+
+    def test_boundaries_match_start_and_stop_exactly(self):
+        # make sure that the boundaries of the returned array exactly
+        # equal 'start' and 'stop' - this isn't obvious because
+        # np.exp(np.log(x)) isn't necessarily exactly equal to x
+        start = 0.3
+        stop = 20.3
+
+        y = geomspace(start, stop, num=1)
+        assert_equal(y[0], start)
+
+        y = geomspace(start, stop, num=1, endpoint=False)
+        assert_equal(y[0], start)
+
+        y = geomspace(start, stop, num=3)
+        assert_equal(y[0], start)
+        assert_equal(y[-1], stop)
+
+        y = geomspace(start, stop, num=3, endpoint=False)
+        assert_equal(y[0], start)
+
+    def test_nan_interior(self):
+        with errstate(invalid='ignore'):
+            y = geomspace(-3, 3, num=4)
+
+        assert_equal(y[0], -3.0)
+        assert_(isnan(y[1:-1]).all())
+        assert_equal(y[3], 3.0)
+
+        with errstate(invalid='ignore'):
+            y = geomspace(-3, 3, num=4, endpoint=False)
+
+        assert_equal(y[0], -3.0)
+        assert_(isnan(y[1:]).all())
+
+    def test_complex(self):
+        # Purely imaginary
+        y = geomspace(1j, 16j, num=5)
+        assert_allclose(y, [1j, 2j, 4j, 8j, 16j])
+        assert_array_equal(y.real, 0)
+
+        y = geomspace(-4j, -324j, num=5)
+        assert_allclose(y, [-4j, -12j, -36j, -108j, -324j])
+        assert_array_equal(y.real, 0)
+
+        y = geomspace(1+1j, 1000+1000j, num=4)
+        assert_allclose(y, [1+1j, 10+10j, 100+100j, 1000+1000j])
+
+        y = geomspace(-1+1j, -1000+1000j, num=4)
+        assert_allclose(y, [-1+1j, -10+10j, -100+100j, -1000+1000j])
+
+        # Logarithmic spirals
+        y = geomspace(-1, 1, num=3, dtype=complex)
+        assert_allclose(y, [-1, 1j, +1])
+
+        y = geomspace(0+3j, -3+0j, 3)
+        assert_allclose(y, [0+3j, -3/sqrt(2)+3j/sqrt(2), -3+0j])
+        y = geomspace(0+3j, 3+0j, 3)
+        assert_allclose(y, [0+3j, 3/sqrt(2)+3j/sqrt(2), 3+0j])
+        y = geomspace(-3+0j, 0-3j, 3)
+        assert_allclose(y, [-3+0j, -3/sqrt(2)-3j/sqrt(2), 0-3j])
+        y = geomspace(0+3j, -3+0j, 3)
+        assert_allclose(y, [0+3j, -3/sqrt(2)+3j/sqrt(2), -3+0j])
+        y = geomspace(-2-3j, 5+7j, 7)
+        assert_allclose(y, [-2-3j, -0.29058977-4.15771027j,
+                            2.08885354-4.34146838j, 4.58345529-3.16355218j,
+                            6.41401745-0.55233457j, 6.75707386+3.11795092j,
+                            5+7j])
+
+        # Type promotion should prevent the -5 from becoming a NaN
+        y = geomspace(3j, -5, 2)
+        assert_allclose(y, [3j, -5])
+        y = geomspace(-5, 3j, 2)
+        assert_allclose(y, [-5, 3j])
+
+    def test_dtype(self):
+        y = geomspace(1, 1e6, dtype='float32')
+        assert_equal(y.dtype, dtype('float32'))
+        y = geomspace(1, 1e6, dtype='float64')
+        assert_equal(y.dtype, dtype('float64'))
+        y = geomspace(1, 1e6, dtype='int32')
+        assert_equal(y.dtype, dtype('int32'))
+
+        # Native types
+        y = geomspace(1, 1e6, dtype=float)
+        assert_equal(y.dtype, dtype('float_'))
+        y = geomspace(1, 1e6, dtype=complex)
+        assert_equal(y.dtype, dtype('complex'))
+
+    def test_start_stop_array_scalar(self):
+        lim1 = array([120, 100], dtype="int8")
+        lim2 = array([-120, -100], dtype="int8")
+        lim3 = array([1200, 1000], dtype="uint16")
+        t1 = geomspace(lim1[0], lim1[1], 5)
+        t2 = geomspace(lim2[0], lim2[1], 5)
+        t3 = geomspace(lim3[0], lim3[1], 5)
+        t4 = geomspace(120.0, 100.0, 5)
+        t5 = geomspace(-120.0, -100.0, 5)
+        t6 = geomspace(1200.0, 1000.0, 5)
+
+        # t3 uses float32, t6 uses float64
+        assert_allclose(t1, t4, rtol=1e-2)
+        assert_allclose(t2, t5, rtol=1e-2)
+        assert_allclose(t3, t6, rtol=1e-5)
+
+    def test_start_stop_array(self):
+        # Try to use all special cases.
+        start = array([1.e0, 32., 1j, -4j, 1+1j, -1])
+        stop = array([1.e4, 2., 16j, -324j, 10000+10000j, 1])
+        t1 = geomspace(start, stop, 5)
+        t2 = stack([geomspace(_start, _stop, 5)
+                    for _start, _stop in zip(start, stop)], axis=1)
+        assert_equal(t1, t2)
+        t3 = geomspace(start, stop[0], 5)
+        t4 = stack([geomspace(_start, stop[0], 5)
+                    for _start in start], axis=1)
+        assert_equal(t3, t4)
+        t5 = geomspace(start, stop, 5, axis=-1)
+        assert_equal(t5, t2.T)
+
+    def test_physical_quantities(self):
+        a = PhysicalQuantity(1.0)
+        b = PhysicalQuantity(5.0)
+        assert_equal(geomspace(a, b), geomspace(1.0, 5.0))
+
+    def test_subclass(self):
+        a = array(1).view(PhysicalQuantity2)
+        b = array(7).view(PhysicalQuantity2)
+        gs = geomspace(a, b)
+        assert type(gs) is PhysicalQuantity2
+        assert_equal(gs, geomspace(1.0, 7.0))
+        gs = geomspace(a, b, 1)
+        assert type(gs) is PhysicalQuantity2
+        assert_equal(gs, geomspace(1.0, 7.0, 1))
+
+    def test_bounds(self):
+        assert_raises(ValueError, geomspace, 0, 10)
+        assert_raises(ValueError, geomspace, 10, 0)
+        assert_raises(ValueError, geomspace, 0, 0)
+
+
+class TestLinspace:
+
+    def test_basic(self):
+        y = linspace(0, 10)
+        assert_(len(y) == 50)
+        y = linspace(2, 10, num=100)
+        assert_(y[-1] == 10)
+        y = linspace(2, 10, endpoint=False)
+        assert_(y[-1] < 10)
+        assert_raises(ValueError, linspace, 0, 10, num=-1)
+
+    def test_corner(self):
+        y = list(linspace(0, 1, 1))
+        assert_(y == [0.0], y)
+        assert_raises(TypeError, linspace, 0, 1, num=2.5)
+
+    def test_type(self):
+        t1 = linspace(0, 1, 0).dtype
+        t2 = linspace(0, 1, 1).dtype
+        t3 = linspace(0, 1, 2).dtype
+        assert_equal(t1, t2)
+        assert_equal(t2, t3)
+
+    def test_dtype(self):
+        y = linspace(0, 6, dtype='float32')
+        assert_equal(y.dtype, dtype('float32'))
+        y = linspace(0, 6, dtype='float64')
+        assert_equal(y.dtype, dtype('float64'))
+        y = linspace(0, 6, dtype='int32')
+        assert_equal(y.dtype, dtype('int32'))
+
+    def test_start_stop_array_scalar(self):
+        lim1 = array([-120, 100], dtype="int8")
+        lim2 = array([120, -100], dtype="int8")
+        lim3 = array([1200, 1000], dtype="uint16")
+        t1 = linspace(lim1[0], lim1[1], 5)
+        t2 = linspace(lim2[0], lim2[1], 5)
+        t3 = linspace(lim3[0], lim3[1], 5)
+        t4 = linspace(-120.0, 100.0, 5)
+        t5 = linspace(120.0, -100.0, 5)
+        t6 = linspace(1200.0, 1000.0, 5)
+        assert_equal(t1, t4)
+        assert_equal(t2, t5)
+        assert_equal(t3, t6)
+
+    def test_start_stop_array(self):
+        start = array([-120, 120], dtype="int8")
+        stop = array([100, -100], dtype="int8")
+        t1 = linspace(start, stop, 5)
+        t2 = stack([linspace(_start, _stop, 5)
+                    for _start, _stop in zip(start, stop)], axis=1)
+        assert_equal(t1, t2)
+        t3 = linspace(start, stop[0], 5)
+        t4 = stack([linspace(_start, stop[0], 5)
+                    for _start in start], axis=1)
+        assert_equal(t3, t4)
+        t5 = linspace(start, stop, 5, axis=-1)
+        assert_equal(t5, t2.T)
+
+    def test_complex(self):
+        lim1 = linspace(1 + 2j, 3 + 4j, 5)
+        t1 = array([1.0+2.j, 1.5+2.5j,  2.0+3j, 2.5+3.5j, 3.0+4j])
+        lim2 = linspace(1j, 10, 5)
+        t2 = array([0.0+1.j, 2.5+0.75j, 5.0+0.5j, 7.5+0.25j, 10.0+0j])
+        assert_equal(lim1, t1)
+        assert_equal(lim2, t2)
+
+    def test_physical_quantities(self):
+        a = PhysicalQuantity(0.0)
+        b = PhysicalQuantity(1.0)
+        assert_equal(linspace(a, b), linspace(0.0, 1.0))
+
+    def test_subclass(self):
+        a = array(0).view(PhysicalQuantity2)
+        b = array(1).view(PhysicalQuantity2)
+        ls = linspace(a, b)
+        assert type(ls) is PhysicalQuantity2
+        assert_equal(ls, linspace(0.0, 1.0))
+        ls = linspace(a, b, 1)
+        assert type(ls) is PhysicalQuantity2
+        assert_equal(ls, linspace(0.0, 1.0, 1))
+
+    def test_array_interface(self):
+        # Regression test for https://github.com/numpy/numpy/pull/6659
+        # Ensure that start/stop can be objects that implement
+        # __array_interface__ and are convertible to numeric scalars
+
+        class Arrayish:
+            """
+            A generic object that supports the __array_interface__ and hence
+            can in principle be converted to a numeric scalar, but is not
+            otherwise recognized as numeric, but also happens to support
+            multiplication by floats.
+
+            Data should be an object that implements the buffer interface,
+            and contains at least 4 bytes.
+            """
+
+            def __init__(self, data):
+                self._data = data
+
+            @property
+            def __array_interface__(self):
+                return {'shape': (), 'typestr': '<i4', 'data': self._data,
+                        'version': 3}
+
+            def __mul__(self, other):
+                # For the purposes of this test any multiplication is an
+                # identity operation :)
+                return self
+
+        one = Arrayish(array(1, dtype='<i4'))
+        five = Arrayish(array(5, dtype='<i4'))
+
+        assert_equal(linspace(one, five), linspace(1, 5))
+
+    def test_denormal_numbers(self):
+        # Regression test for gh-5437. Will probably fail when compiled
+        # with ICC, which flushes denormals to zero
+        for ftype in sctypes['float']:
+            stop = nextafter(ftype(0), ftype(1)) * 5  # A denormal number
+            assert_(any(linspace(0, stop, 10, endpoint=False, dtype=ftype)))
+
+    def test_equivalent_to_arange(self):
+        for j in range(1000):
+            assert_equal(linspace(0, j, j+1, dtype=int),
+                         arange(j+1, dtype=int))
+
+    def test_retstep(self):
+        for num in [0, 1, 2]:
+            for ept in [False, True]:
+                y = linspace(0, 1, num, endpoint=ept, retstep=True)
+                assert isinstance(y, tuple) and len(y) == 2
+                if num == 2:
+                    y0_expect = [0.0, 1.0] if ept else [0.0, 0.5]
+                    assert_array_equal(y[0], y0_expect)
+                    assert_equal(y[1], y0_expect[1])
+                elif num == 1 and not ept:
+                    assert_array_equal(y[0], [0.0])
+                    assert_equal(y[1], 1.0)
+                else:
+                    assert_array_equal(y[0], [0.0][:num])
+                    assert isnan(y[1])
+
+    def test_object(self):
+        start = array(1, dtype='O')
+        stop = array(2, dtype='O')
+        y = linspace(start, stop, 3)
+        assert_array_equal(y, array([1., 1.5, 2.]))
+                    
+    def test_round_negative(self):
+        y = linspace(-1, 3, num=8, dtype=int)
+        t = array([-1, -1, 0, 0, 1, 1, 2, 3], dtype=int)
+        assert_array_equal(y, t)
+
+    def test_any_step_zero_and_not_mult_inplace(self):
+        # any_step_zero is True, _mult_inplace is False
+        start = array([0.0, 1.0])
+        stop = array([2.0, 1.0])
+        y = linspace(start, stop, 3)
+        assert_array_equal(y, array([[0.0, 1.0], [1.0, 1.0], [2.0, 1.0]]))
+    
+

.venv/lib/python3.11/site-packages/numpy/core/tests/test_half.py

@@ -0,0 +1,572 @@
+import platform
+import pytest
+
+import numpy as np
+from numpy import uint16, float16, float32, float64
+from numpy.testing import assert_, assert_equal, _OLD_PROMOTION, IS_WASM
+
+
+def assert_raises_fpe(strmatch, callable, *args, **kwargs):
+    try:
+        callable(*args, **kwargs)
+    except FloatingPointError as exc:
+        assert_(str(exc).find(strmatch) >= 0,
+                "Did not raise floating point %s error" % strmatch)
+    else:
+        assert_(False,
+                "Did not raise floating point %s error" % strmatch)
+
+class TestHalf:
+    def setup_method(self):
+        # An array of all possible float16 values
+        self.all_f16 = np.arange(0x10000, dtype=uint16)
+        self.all_f16.dtype = float16
+
+        # NaN value can cause an invalid FP exception if HW is been used
+        with np.errstate(invalid='ignore'):
+            self.all_f32 = np.array(self.all_f16, dtype=float32)
+            self.all_f64 = np.array(self.all_f16, dtype=float64)
+
+        # An array of all non-NaN float16 values, in sorted order
+        self.nonan_f16 = np.concatenate(
+                                (np.arange(0xfc00, 0x7fff, -1, dtype=uint16),
+                                 np.arange(0x0000, 0x7c01, 1, dtype=uint16)))
+        self.nonan_f16.dtype = float16
+        self.nonan_f32 = np.array(self.nonan_f16, dtype=float32)
+        self.nonan_f64 = np.array(self.nonan_f16, dtype=float64)
+
+        # An array of all finite float16 values, in sorted order
+        self.finite_f16 = self.nonan_f16[1:-1]
+        self.finite_f32 = self.nonan_f32[1:-1]
+        self.finite_f64 = self.nonan_f64[1:-1]
+
+    def test_half_conversions(self):
+        """Checks that all 16-bit values survive conversion
+           to/from 32-bit and 64-bit float"""
+        # Because the underlying routines preserve the NaN bits, every
+        # value is preserved when converting to/from other floats.
+
+        # Convert from float32 back to float16
+        with np.errstate(invalid='ignore'):
+            b = np.array(self.all_f32, dtype=float16)
+        # avoid testing NaNs due to differ bits wither Q/SNaNs
+        b_nn = b == b
+        assert_equal(self.all_f16[b_nn].view(dtype=uint16),
+                     b[b_nn].view(dtype=uint16))
+
+        # Convert from float64 back to float16
+        with np.errstate(invalid='ignore'):
+            b = np.array(self.all_f64, dtype=float16)
+        b_nn = b == b
+        assert_equal(self.all_f16[b_nn].view(dtype=uint16),
+                     b[b_nn].view(dtype=uint16))
+
+        # Convert float16 to longdouble and back
+        # This doesn't necessarily preserve the extra NaN bits,
+        # so exclude NaNs.
+        a_ld = np.array(self.nonan_f16, dtype=np.longdouble)
+        b = np.array(a_ld, dtype=float16)
+        assert_equal(self.nonan_f16.view(dtype=uint16),
+                     b.view(dtype=uint16))
+
+        # Check the range for which all integers can be represented
+        i_int = np.arange(-2048, 2049)
+        i_f16 = np.array(i_int, dtype=float16)
+        j = np.array(i_f16, dtype=int)
+        assert_equal(i_int, j)
+
+    @pytest.mark.parametrize("string_dt", ["S", "U"])
+    def test_half_conversion_to_string(self, string_dt):
+        # Currently uses S/U32 (which is sufficient for float32)
+        expected_dt = np.dtype(f"{string_dt}32")
+        assert np.promote_types(np.float16, string_dt) == expected_dt
+        assert np.promote_types(string_dt, np.float16) == expected_dt
+
+        arr = np.ones(3, dtype=np.float16).astype(string_dt)
+        assert arr.dtype == expected_dt
+
+    @pytest.mark.parametrize("string_dt", ["S", "U"])
+    def test_half_conversion_from_string(self, string_dt):
+        string = np.array("3.1416", dtype=string_dt)
+        assert string.astype(np.float16) == np.array(3.1416, dtype=np.float16)
+
+    @pytest.mark.parametrize("offset", [None, "up", "down"])
+    @pytest.mark.parametrize("shift", [None, "up", "down"])
+    @pytest.mark.parametrize("float_t", [np.float32, np.float64])
+    @np._no_nep50_warning()
+    def test_half_conversion_rounding(self, float_t, shift, offset):
+        # Assumes that round to even is used during casting.
+        max_pattern = np.float16(np.finfo(np.float16).max).view(np.uint16)
+
+        # Test all (positive) finite numbers, denormals are most interesting
+        # however:
+        f16s_patterns = np.arange(0, max_pattern+1, dtype=np.uint16)
+        f16s_float = f16s_patterns.view(np.float16).astype(float_t)
+
+        # Shift the values by half a bit up or a down (or do not shift),
+        if shift == "up":
+            f16s_float = 0.5 * (f16s_float[:-1] + f16s_float[1:])[1:]
+        elif shift == "down":
+            f16s_float = 0.5 * (f16s_float[:-1] + f16s_float[1:])[:-1]
+        else:
+            f16s_float = f16s_float[1:-1]
+
+        # Increase the float by a minimal value:
+        if offset == "up":
+            f16s_float = np.nextafter(f16s_float, float_t(np.inf))
+        elif offset == "down":
+            f16s_float = np.nextafter(f16s_float, float_t(-np.inf))
+
+        # Convert back to float16 and its bit pattern:
+        res_patterns = f16s_float.astype(np.float16).view(np.uint16)
+
+        # The above calculations tries the original values, or the exact
+        # mid points between the float16 values. It then further offsets them
+        # by as little as possible. If no offset occurs, "round to even"
+        # logic will be necessary, an arbitrarily small offset should cause
+        # normal up/down rounding always.
+
+        # Calculate the expected pattern:
+        cmp_patterns = f16s_patterns[1:-1].copy()
+
+        if shift == "down" and offset != "up":
+            shift_pattern = -1
+        elif shift == "up" and offset != "down":
+            shift_pattern = 1
+        else:
+            # There cannot be a shift, either shift is None, so all rounding
+            # will go back to original, or shift is reduced by offset too much.
+            shift_pattern = 0
+
+        # If rounding occurs, is it normal rounding or round to even?
+        if offset is None:
+            # Round to even occurs, modify only non-even, cast to allow + (-1)
+            cmp_patterns[0::2].view(np.int16)[...] += shift_pattern
+        else:
+            cmp_patterns.view(np.int16)[...] += shift_pattern
+
+        assert_equal(res_patterns, cmp_patterns)
+
+    @pytest.mark.parametrize(["float_t", "uint_t", "bits"],
+                             [(np.float32, np.uint32, 23),
+                              (np.float64, np.uint64, 52)])
+    def test_half_conversion_denormal_round_even(self, float_t, uint_t, bits):
+        # Test specifically that all bits are considered when deciding
+        # whether round to even should occur (i.e. no bits are lost at the
+        # end. Compare also gh-12721. The most bits can get lost for the
+        # smallest denormal:
+        smallest_value = np.uint16(1).view(np.float16).astype(float_t)
+        assert smallest_value == 2**-24
+
+        # Will be rounded to zero based on round to even rule:
+        rounded_to_zero = smallest_value / float_t(2)
+        assert rounded_to_zero.astype(np.float16) == 0
+
+        # The significand will be all 0 for the float_t, test that we do not
+        # lose the lower ones of these:
+        for i in range(bits):
+            # slightly increasing the value should make it round up:
+            larger_pattern = rounded_to_zero.view(uint_t) | uint_t(1 << i)
+            larger_value = larger_pattern.view(float_t)
+            assert larger_value.astype(np.float16) == smallest_value
+
+    def test_nans_infs(self):
+        with np.errstate(all='ignore'):
+            # Check some of the ufuncs
+            assert_equal(np.isnan(self.all_f16), np.isnan(self.all_f32))
+            assert_equal(np.isinf(self.all_f16), np.isinf(self.all_f32))
+            assert_equal(np.isfinite(self.all_f16), np.isfinite(self.all_f32))
+            assert_equal(np.signbit(self.all_f16), np.signbit(self.all_f32))
+            assert_equal(np.spacing(float16(65504)), np.inf)
+
+            # Check comparisons of all values with NaN
+            nan = float16(np.nan)
+
+            assert_(not (self.all_f16 == nan).any())
+            assert_(not (nan == self.all_f16).any())
+
+            assert_((self.all_f16 != nan).all())
+            assert_((nan != self.all_f16).all())
+
+            assert_(not (self.all_f16 < nan).any())
+            assert_(not (nan < self.all_f16).any())
+
+            assert_(not (self.all_f16 <= nan).any())
+            assert_(not (nan <= self.all_f16).any())
+
+            assert_(not (self.all_f16 > nan).any())
+            assert_(not (nan > self.all_f16).any())
+
+            assert_(not (self.all_f16 >= nan).any())
+            assert_(not (nan >= self.all_f16).any())
+
+    def test_half_values(self):
+        """Confirms a small number of known half values"""
+        a = np.array([1.0, -1.0,
+                      2.0, -2.0,
+                      0.0999755859375, 0.333251953125,  # 1/10, 1/3
+                      65504, -65504,           # Maximum magnitude
+                      2.0**(-14), -2.0**(-14),  # Minimum normal
+                      2.0**(-24), -2.0**(-24),  # Minimum subnormal
+                      0, -1/1e1000,            # Signed zeros
+                      np.inf, -np.inf])
+        b = np.array([0x3c00, 0xbc00,
+                      0x4000, 0xc000,
+                      0x2e66, 0x3555,
+                      0x7bff, 0xfbff,
+                      0x0400, 0x8400,
+                      0x0001, 0x8001,
+                      0x0000, 0x8000,
+                      0x7c00, 0xfc00], dtype=uint16)
+        b.dtype = float16
+        assert_equal(a, b)
+
+    def test_half_rounding(self):
+        """Checks that rounding when converting to half is correct"""
+        a = np.array([2.0**-25 + 2.0**-35,  # Rounds to minimum subnormal
+                      2.0**-25,       # Underflows to zero (nearest even mode)
+                      2.0**-26,       # Underflows to zero
+                      1.0+2.0**-11 + 2.0**-16,  # rounds to 1.0+2**(-10)
+                      1.0+2.0**-11,   # rounds to 1.0 (nearest even mode)
+                      1.0+2.0**-12,   # rounds to 1.0
+                      65519,          # rounds to 65504
+                      65520],         # rounds to inf
+                      dtype=float64)
+        rounded = [2.0**-24,
+                   0.0,
+                   0.0,
+                   1.0+2.0**(-10),
+                   1.0,
+                   1.0,
+                   65504,
+                   np.inf]
+
+        # Check float64->float16 rounding
+        with np.errstate(over="ignore"):
+            b = np.array(a, dtype=float16)
+        assert_equal(b, rounded)
+
+        # Check float32->float16 rounding
+        a = np.array(a, dtype=float32)
+        with np.errstate(over="ignore"):
+            b = np.array(a, dtype=float16)
+        assert_equal(b, rounded)
+
+    def test_half_correctness(self):
+        """Take every finite float16, and check the casting functions with
+           a manual conversion."""
+
+        # Create an array of all finite float16s
+        a_bits = self.finite_f16.view(dtype=uint16)
+
+        # Convert to 64-bit float manually
+        a_sgn = (-1.0)**((a_bits & 0x8000) >> 15)
+        a_exp = np.array((a_bits & 0x7c00) >> 10, dtype=np.int32) - 15
+        a_man = (a_bits & 0x03ff) * 2.0**(-10)
+        # Implicit bit of normalized floats
+        a_man[a_exp != -15] += 1
+        # Denormalized exponent is -14
+        a_exp[a_exp == -15] = -14
+
+        a_manual = a_sgn * a_man * 2.0**a_exp
+
+        a32_fail = np.nonzero(self.finite_f32 != a_manual)[0]
+        if len(a32_fail) != 0:
+            bad_index = a32_fail[0]
+            assert_equal(self.finite_f32, a_manual,
+                 "First non-equal is half value 0x%x -> %g != %g" %
+                            (a_bits[bad_index],
+                             self.finite_f32[bad_index],
+                             a_manual[bad_index]))
+
+        a64_fail = np.nonzero(self.finite_f64 != a_manual)[0]
+        if len(a64_fail) != 0:
+            bad_index = a64_fail[0]
+            assert_equal(self.finite_f64, a_manual,
+                 "First non-equal is half value 0x%x -> %g != %g" %
+                            (a_bits[bad_index],
+                             self.finite_f64[bad_index],
+                             a_manual[bad_index]))
+
+    def test_half_ordering(self):
+        """Make sure comparisons are working right"""
+
+        # All non-NaN float16 values in reverse order
+        a = self.nonan_f16[::-1].copy()
+
+        # 32-bit float copy
+        b = np.array(a, dtype=float32)
+
+        # Should sort the same
+        a.sort()
+        b.sort()
+        assert_equal(a, b)
+
+        # Comparisons should work
+        assert_((a[:-1] <= a[1:]).all())
+        assert_(not (a[:-1] > a[1:]).any())
+        assert_((a[1:] >= a[:-1]).all())
+        assert_(not (a[1:] < a[:-1]).any())
+        # All != except for +/-0
+        assert_equal(np.nonzero(a[:-1] < a[1:])[0].size, a.size-2)
+        assert_equal(np.nonzero(a[1:] > a[:-1])[0].size, a.size-2)
+
+    def test_half_funcs(self):
+        """Test the various ArrFuncs"""
+
+        # fill
+        assert_equal(np.arange(10, dtype=float16),
+                     np.arange(10, dtype=float32))
+
+        # fillwithscalar
+        a = np.zeros((5,), dtype=float16)
+        a.fill(1)
+        assert_equal(a, np.ones((5,), dtype=float16))
+
+        # nonzero and copyswap
+        a = np.array([0, 0, -1, -1/1e20, 0, 2.0**-24, 7.629e-6], dtype=float16)
+        assert_equal(a.nonzero()[0],
+                     [2, 5, 6])
+        a = a.byteswap()
+        a = a.view(a.dtype.newbyteorder())
+        assert_equal(a.nonzero()[0],
+                     [2, 5, 6])
+
+        # dot
+        a = np.arange(0, 10, 0.5, dtype=float16)
+        b = np.ones((20,), dtype=float16)
+        assert_equal(np.dot(a, b),
+                     95)
+
+        # argmax
+        a = np.array([0, -np.inf, -2, 0.5, 12.55, 7.3, 2.1, 12.4], dtype=float16)
+        assert_equal(a.argmax(),
+                     4)
+        a = np.array([0, -np.inf, -2, np.inf, 12.55, np.nan, 2.1, 12.4], dtype=float16)
+        assert_equal(a.argmax(),
+                     5)
+
+        # getitem
+        a = np.arange(10, dtype=float16)
+        for i in range(10):
+            assert_equal(a.item(i), i)
+
+    def test_spacing_nextafter(self):
+        """Test np.spacing and np.nextafter"""
+        # All non-negative finite #'s
+        a = np.arange(0x7c00, dtype=uint16)
+        hinf = np.array((np.inf,), dtype=float16)
+        hnan = np.array((np.nan,), dtype=float16)
+        a_f16 = a.view(dtype=float16)
+
+        assert_equal(np.spacing(a_f16[:-1]), a_f16[1:]-a_f16[:-1])
+
+        assert_equal(np.nextafter(a_f16[:-1], hinf), a_f16[1:])
+        assert_equal(np.nextafter(a_f16[0], -hinf), -a_f16[1])
+        assert_equal(np.nextafter(a_f16[1:], -hinf), a_f16[:-1])
+
+        assert_equal(np.nextafter(hinf, a_f16), a_f16[-1])
+        assert_equal(np.nextafter(-hinf, a_f16), -a_f16[-1])
+
+        assert_equal(np.nextafter(hinf, hinf), hinf)
+        assert_equal(np.nextafter(hinf, -hinf), a_f16[-1])
+        assert_equal(np.nextafter(-hinf, hinf), -a_f16[-1])
+        assert_equal(np.nextafter(-hinf, -hinf), -hinf)
+
+        assert_equal(np.nextafter(a_f16, hnan), hnan[0])
+        assert_equal(np.nextafter(hnan, a_f16), hnan[0])
+
+        assert_equal(np.nextafter(hnan, hnan), hnan)
+        assert_equal(np.nextafter(hinf, hnan), hnan)
+        assert_equal(np.nextafter(hnan, hinf), hnan)
+
+        # switch to negatives
+        a |= 0x8000
+
+        assert_equal(np.spacing(a_f16[0]), np.spacing(a_f16[1]))
+        assert_equal(np.spacing(a_f16[1:]), a_f16[:-1]-a_f16[1:])
+
+        assert_equal(np.nextafter(a_f16[0], hinf), -a_f16[1])
+        assert_equal(np.nextafter(a_f16[1:], hinf), a_f16[:-1])
+        assert_equal(np.nextafter(a_f16[:-1], -hinf), a_f16[1:])
+
+        assert_equal(np.nextafter(hinf, a_f16), -a_f16[-1])
+        assert_equal(np.nextafter(-hinf, a_f16), a_f16[-1])
+
+        assert_equal(np.nextafter(a_f16, hnan), hnan[0])
+        assert_equal(np.nextafter(hnan, a_f16), hnan[0])
+
+    def test_half_ufuncs(self):
+        """Test the various ufuncs"""
+
+        a = np.array([0, 1, 2, 4, 2], dtype=float16)
+        b = np.array([-2, 5, 1, 4, 3], dtype=float16)
+        c = np.array([0, -1, -np.inf, np.nan, 6], dtype=float16)
+
+        assert_equal(np.add(a, b), [-2, 6, 3, 8, 5])
+        assert_equal(np.subtract(a, b), [2, -4, 1, 0, -1])
+        assert_equal(np.multiply(a, b), [0, 5, 2, 16, 6])
+        assert_equal(np.divide(a, b), [0, 0.199951171875, 2, 1, 0.66650390625])
+
+        assert_equal(np.equal(a, b), [False, False, False, True, False])
+        assert_equal(np.not_equal(a, b), [True, True, True, False, True])
+        assert_equal(np.less(a, b), [False, True, False, False, True])
+        assert_equal(np.less_equal(a, b), [False, True, False, True, True])
+        assert_equal(np.greater(a, b), [True, False, True, False, False])
+        assert_equal(np.greater_equal(a, b), [True, False, True, True, False])
+        assert_equal(np.logical_and(a, b), [False, True, True, True, True])
+        assert_equal(np.logical_or(a, b), [True, True, True, True, True])
+        assert_equal(np.logical_xor(a, b), [True, False, False, False, False])
+        assert_equal(np.logical_not(a), [True, False, False, False, False])
+
+        assert_equal(np.isnan(c), [False, False, False, True, False])
+        assert_equal(np.isinf(c), [False, False, True, False, False])
+        assert_equal(np.isfinite(c), [True, True, False, False, True])
+        assert_equal(np.signbit(b), [True, False, False, False, False])
+
+        assert_equal(np.copysign(b, a), [2, 5, 1, 4, 3])
+
+        assert_equal(np.maximum(a, b), [0, 5, 2, 4, 3])
+
+        x = np.maximum(b, c)
+        assert_(np.isnan(x[3]))
+        x[3] = 0
+        assert_equal(x, [0, 5, 1, 0, 6])
+
+        assert_equal(np.minimum(a, b), [-2, 1, 1, 4, 2])
+
+        x = np.minimum(b, c)
+        assert_(np.isnan(x[3]))
+        x[3] = 0
+        assert_equal(x, [-2, -1, -np.inf, 0, 3])
+
+        assert_equal(np.fmax(a, b), [0, 5, 2, 4, 3])
+        assert_equal(np.fmax(b, c), [0, 5, 1, 4, 6])
+        assert_equal(np.fmin(a, b), [-2, 1, 1, 4, 2])
+        assert_equal(np.fmin(b, c), [-2, -1, -np.inf, 4, 3])
+
+        assert_equal(np.floor_divide(a, b), [0, 0, 2, 1, 0])
+        assert_equal(np.remainder(a, b), [0, 1, 0, 0, 2])
+        assert_equal(np.divmod(a, b), ([0, 0, 2, 1, 0], [0, 1, 0, 0, 2]))
+        assert_equal(np.square(b), [4, 25, 1, 16, 9])
+        assert_equal(np.reciprocal(b), [-0.5, 0.199951171875, 1, 0.25, 0.333251953125])
+        assert_equal(np.ones_like(b), [1, 1, 1, 1, 1])
+        assert_equal(np.conjugate(b), b)
+        assert_equal(np.absolute(b), [2, 5, 1, 4, 3])
+        assert_equal(np.negative(b), [2, -5, -1, -4, -3])
+        assert_equal(np.positive(b), b)
+        assert_equal(np.sign(b), [-1, 1, 1, 1, 1])
+        assert_equal(np.modf(b), ([0, 0, 0, 0, 0], b))
+        assert_equal(np.frexp(b), ([-0.5, 0.625, 0.5, 0.5, 0.75], [2, 3, 1, 3, 2]))
+        assert_equal(np.ldexp(b, [0, 1, 2, 4, 2]), [-2, 10, 4, 64, 12])
+
+    @np._no_nep50_warning()
+    def test_half_coercion(self, weak_promotion):
+        """Test that half gets coerced properly with the other types"""
+        a16 = np.array((1,), dtype=float16)
+        a32 = np.array((1,), dtype=float32)
+        b16 = float16(1)
+        b32 = float32(1)
+
+        assert np.power(a16, 2).dtype == float16
+        assert np.power(a16, 2.0).dtype == float16
+        assert np.power(a16, b16).dtype == float16
+        expected_dt = float32 if weak_promotion else float16
+        assert np.power(a16, b32).dtype == expected_dt
+        assert np.power(a16, a16).dtype == float16
+        assert np.power(a16, a32).dtype == float32
+
+        expected_dt = float16 if weak_promotion else float64
+        assert np.power(b16, 2).dtype == expected_dt
+        assert np.power(b16, 2.0).dtype == expected_dt
+        assert np.power(b16, b16).dtype, float16
+        assert np.power(b16, b32).dtype, float32
+        assert np.power(b16, a16).dtype, float16
+        assert np.power(b16, a32).dtype, float32
+
+        assert np.power(a32, a16).dtype == float32
+        assert np.power(a32, b16).dtype == float32
+        expected_dt = float32 if weak_promotion else float16
+        assert np.power(b32, a16).dtype == expected_dt
+        assert np.power(b32, b16).dtype == float32
+
+    @pytest.mark.skipif(platform.machine() == "armv5tel",
+                        reason="See gh-413.")
+    @pytest.mark.skipif(IS_WASM,
+                        reason="fp exceptions don't work in wasm.")
+    def test_half_fpe(self):
+        with np.errstate(all='raise'):
+            sx16 = np.array((1e-4,), dtype=float16)
+            bx16 = np.array((1e4,), dtype=float16)
+            sy16 = float16(1e-4)
+            by16 = float16(1e4)
+
+            # Underflow errors
+            assert_raises_fpe('underflow', lambda a, b:a*b, sx16, sx16)
+            assert_raises_fpe('underflow', lambda a, b:a*b, sx16, sy16)
+            assert_raises_fpe('underflow', lambda a, b:a*b, sy16, sx16)
+            assert_raises_fpe('underflow', lambda a, b:a*b, sy16, sy16)
+            assert_raises_fpe('underflow', lambda a, b:a/b, sx16, bx16)
+            assert_raises_fpe('underflow', lambda a, b:a/b, sx16, by16)
+            assert_raises_fpe('underflow', lambda a, b:a/b, sy16, bx16)
+            assert_raises_fpe('underflow', lambda a, b:a/b, sy16, by16)
+            assert_raises_fpe('underflow', lambda a, b:a/b,
+                                             float16(2.**-14), float16(2**11))
+            assert_raises_fpe('underflow', lambda a, b:a/b,
+                                             float16(-2.**-14), float16(2**11))
+            assert_raises_fpe('underflow', lambda a, b:a/b,
+                                             float16(2.**-14+2**-24), float16(2))
+            assert_raises_fpe('underflow', lambda a, b:a/b,
+                                             float16(-2.**-14-2**-24), float16(2))
+            assert_raises_fpe('underflow', lambda a, b:a/b,
+                                             float16(2.**-14+2**-23), float16(4))
+
+            # Overflow errors
+            assert_raises_fpe('overflow', lambda a, b:a*b, bx16, bx16)
+            assert_raises_fpe('overflow', lambda a, b:a*b, bx16, by16)
+            assert_raises_fpe('overflow', lambda a, b:a*b, by16, bx16)
+            assert_raises_fpe('overflow', lambda a, b:a*b, by16, by16)
+            assert_raises_fpe('overflow', lambda a, b:a/b, bx16, sx16)
+            assert_raises_fpe('overflow', lambda a, b:a/b, bx16, sy16)
+            assert_raises_fpe('overflow', lambda a, b:a/b, by16, sx16)
+            assert_raises_fpe('overflow', lambda a, b:a/b, by16, sy16)
+            assert_raises_fpe('overflow', lambda a, b:a+b,
+                                             float16(65504), float16(17))
+            assert_raises_fpe('overflow', lambda a, b:a-b,
+                                             float16(-65504), float16(17))
+            assert_raises_fpe('overflow', np.nextafter, float16(65504), float16(np.inf))
+            assert_raises_fpe('overflow', np.nextafter, float16(-65504), float16(-np.inf))
+            assert_raises_fpe('overflow', np.spacing, float16(65504))
+
+            # Invalid value errors
+            assert_raises_fpe('invalid', np.divide, float16(np.inf), float16(np.inf))
+            assert_raises_fpe('invalid', np.spacing, float16(np.inf))
+            assert_raises_fpe('invalid', np.spacing, float16(np.nan))
+
+            # These should not raise
+            float16(65472)+float16(32)
+            float16(2**-13)/float16(2)
+            float16(2**-14)/float16(2**10)
+            np.spacing(float16(-65504))
+            np.nextafter(float16(65504), float16(-np.inf))
+            np.nextafter(float16(-65504), float16(np.inf))
+            np.nextafter(float16(np.inf), float16(0))
+            np.nextafter(float16(-np.inf), float16(0))
+            np.nextafter(float16(0), float16(np.nan))
+            np.nextafter(float16(np.nan), float16(0))
+            float16(2**-14)/float16(2**10)
+            float16(-2**-14)/float16(2**10)
+            float16(2**-14+2**-23)/float16(2)
+            float16(-2**-14-2**-23)/float16(2)
+
+    def test_half_array_interface(self):
+        """Test that half is compatible with __array_interface__"""
+        class Dummy:
+            pass
+
+        a = np.ones((1,), dtype=float16)
+        b = Dummy()
+        b.__array_interface__ = a.__array_interface__
+        c = np.array(b)
+        assert_(c.dtype == float16)
+        assert_equal(a, c)