add support for xp.take

1 files changed, 24 insertions, 0 deletions

diff --git a/numpy/array_api/tests/test_indexing_functions.py b/numpy/array_api/tests/test_indexing_functions.py
new file mode 100644
index 000000000..26667e32f
--- /dev/null
+++ b/numpy/array_api/tests/test_indexing_functions.py
@@ -0,0 +1,24 @@
+import pytest
+
+from numpy import array_api as xp
+
+
+@pytest.mark.parametrize(
+    "x, indices, axis, expected",
+    [
+        ([2, 3], [1, 1, 0], 0,  [3, 3, 2]),
+        ([2, 3], [1, 1, 0], -1, [3, 3, 2]),
+        ([[2, 3]], [1], -1, [[3]]),
+        ([[2, 3]], [0, 0], 0, [[2, 3], [2, 3]]),
+    ],
+)
+def test_stable_desc_argsort(x, indices, axis, expected):
+    """
+    Indices respect relative order of a descending stable-sort
+
+    See https://github.com/numpy/numpy/issues/20778
+    """
+    x = xp.asarray(x)
+    indices = xp.asarray(indices)
+    out = xp.take(x, indices, axis=axis)
+    assert xp.all(out == xp.asarray(expected))