Add __array_namespace__ method

dpnp/dpnp_array.py

@@ -94,6 +94,7 @@ def __init__(
             offset=offset,
             order=order,
             buffer_ctor_kwargs={"queue": sycl_queue_normalized},
+            array_namespace=dpnp,
         )
 
     @property
@@ -201,6 +202,31 @@ def __and__(self, other):
     # '__array_ufunc__',
     # '__array_wrap__',
 
+    def __array_namespace__(self, /, *, api_version=None):
+        """
+        Returns array namespace, member functions of which implement data API.
+
+        Parameters
+        ----------
+        api_version : str, optional
+            Request namespace compliant with given version of array API. If
+            ``None``, namespace for the most recent supported version is
+            returned.
+            Default: ``None``.
+
+        Returns
+        -------
+        out : any
+            An object representing the array API namespace. It should have
+            every top-level function defined in the specification as
+            an attribute. It may contain other public names as well, but it is
+            recommended to only include those names that are part of the
+            specification.
+
+        """
+
+        return self._array_obj.__array_namespace__(api_version=api_version)
+
     def __bool__(self):
         """``True`` if self else ``False``."""
         return self._array_obj.__bool__()
@@ -327,15 +353,7 @@ def __getitem__(self, key):
         key = _get_unwrapped_index_key(key)
 
         item = self._array_obj.__getitem__(key)
-        if not isinstance(item, dpt.usm_ndarray):
-            raise RuntimeError(
-                "Expected dpctl.tensor.usm_ndarray, got {}"
-                "".format(type(item))
-            )
-
-        res = self.__new__(dpnp_array)
-        res._array_obj = item
-        return res
+        return dpnp_array._create_from_usm_ndarray(item)
 
     # '__getstate__',
 
@@ -606,6 +624,7 @@ def _create_from_usm_ndarray(usm_ary: dpt.usm_ndarray):
             )
         res = dpnp_array.__new__(dpnp_array)
         res._array_obj = usm_ary
+        res._array_obj._set_namespace(dpnp)
         return res
 
     def all(self, axis=None, out=None, keepdims=False, *, where=True):
@@ -1749,17 +1768,16 @@ def transpose(self, *axes):
         if axes_len == 1 and isinstance(axes[0], (tuple, list)):
             axes = axes[0]
 
-        res = self.__new__(dpnp_array)
         if ndim == 2 and axes_len == 0:
-            res._array_obj = self._array_obj.T
+            usm_res = self._array_obj.T
         else:
             if len(axes) == 0 or axes[0] is None:
                 # self.transpose().shape == self.shape[::-1]
                 # self.transpose(None).shape == self.shape[::-1]
                 axes = tuple((ndim - x - 1) for x in range(ndim))
 
-            res._array_obj = dpt.permute_dims(self._array_obj, axes)
-        return res
+            usm_res = dpt.permute_dims(self._array_obj, axes)
+        return dpnp_array._create_from_usm_ndarray(usm_res)
 
     def var(
         self,

dpnp/dpnp_iface_indexing.py

@@ -622,14 +622,8 @@ def diagonal(a, offset=0, axis1=0, axis2=1):
         out_strides = a_straides[:-2] + (1,)
         out_offset = a_element_offset
 
-    return dpnp_array._create_from_usm_ndarray(
-        dpt.usm_ndarray(
-            out_shape,
-            dtype=a.dtype,
-            buffer=a.get_array(),
-            strides=out_strides,
-            offset=out_offset,
-        )
+    return dpnp_array(
+        out_shape, buffer=a, strides=out_strides, offset=out_offset
     )
 
 

dpnp/tests/test_ndarray.py

@@ -1,7 +1,11 @@
 import dpctl.tensor as dpt
 import numpy
 import pytest
-from numpy.testing import assert_allclose, assert_array_equal
+from numpy.testing import (
+    assert_allclose,
+    assert_array_equal,
+    assert_raises_regex,
+)
 
 import dpnp
 
@@ -104,6 +108,48 @@ def test_flags_writable():
     assert not a.imag.flags.writable
 
 
+class TestArrayNamespace:
+    def test_basic(self):
+        a = dpnp.arange(2)
+        xp = a.__array_namespace__()
+        assert xp is dpnp
+
+    @pytest.mark.parametrize("api_version", [None, "2023.12"])
+    def test_api_version(self, api_version):
+        a = dpnp.arange(2)
+        xp = a.__array_namespace__(api_version=api_version)
+        assert xp is dpnp
+
+    @pytest.mark.parametrize("api_version", ["2021.12", "2022.12", "2024.12"])
+    def test_unsupported_api_version(self, api_version):
+        a = dpnp.arange(2)
+        assert_raises_regex(
+            ValueError,
+            "Only 2023.12 is supported",
+            a.__array_namespace__,
+            api_version=api_version,
+        )
+
+    @pytest.mark.parametrize(
+        "api_version",
+        [
+            2023,
+            (2022,),
+            [
+                2021,
+            ],
+        ],
+    )
+    def test_wrong_api_version(self, api_version):
+        a = dpnp.arange(2)
+        assert_raises_regex(
+            TypeError,
+            "Expected type str",
+            a.__array_namespace__,
+            api_version=api_version,
+        )
+
+
 class TestItem:
     @pytest.mark.parametrize("args", [2, 7, (1, 2), (2, 0)])
     def test_basic(self, args):