Merge pull request #20499 from asmeurer/array_api_T

BUG: Fix the .T attribute in the array_api namespace

2 files changed, 15 insertions, 1 deletions

diff --git a/numpy/array_api/_array_object.py b/numpy/array_api/_array_object.py
index 8794c5ea5..ead061882 100644
--- a/numpy/array_api/_array_object.py
+++ b/numpy/array_api/_array_object.py
@@ -1072,4 +1072,4 @@ class Array:
         # https://data-apis.org/array-api/latest/API_specification/array_object.html#t
         if self.ndim != 2:
             raise ValueError("x.T requires x to have 2 dimensions. Use x.mT to transpose stacks of matrices and permute_dims() to permute dimensions.")
-        return self._array.T
+        return self.__class__._new(self._array.T)
diff --git a/numpy/array_api/tests/test_array_object.py b/numpy/array_api/tests/test_array_object.py
index 12479d765..deab50693 100644
--- a/numpy/array_api/tests/test_array_object.py
+++ b/numpy/array_api/tests/test_array_object.py
@@ -4,6 +4,7 @@ from numpy.testing import assert_raises
 import numpy as np
 
 from .. import ones, asarray, result_type, all, equal
+from .._array_object import Array
 from .._dtypes import (
     _all_dtypes,
     _boolean_dtypes,
@@ -301,3 +302,16 @@ def test_device_property():
 
     assert all(equal(asarray(a, device='cpu'), a))
     assert_raises(ValueError, lambda: asarray(a, device='gpu'))
+
+def test_array_properties():
+    a = ones((1, 2, 3))
+    b = ones((2, 3))
+    assert_raises(ValueError, lambda: a.T)
+
+    assert isinstance(b.T, Array)
+    assert b.T.shape == (3, 2)
+
+    assert isinstance(a.mT, Array)
+    assert a.mT.shape == (1, 3, 2)
+    assert isinstance(b.mT, Array)
+    assert b.mT.shape == (3, 2)