ENH: add check_namespace to testing utilities

src/array_api_extra/_lib/_testing.py

@@ -34,6 +34,7 @@
 def _check_ns_shape_dtype(
     actual: Array,
     desired: Array,
+    check_namespace: bool,
     check_dtype: bool,
     check_shape: bool,
     check_scalar: bool,
@@ -47,6 +48,8 @@ def _check_ns_shape_dtype(
         The array produced by the tested function.
     desired : Array
         The expected array (typically hardcoded).
+    check_namespace : bool, default: True
+        Whether to check agreement between actual and desired namespace.
     check_dtype, check_shape : bool, default: True
         Whether to check agreement between actual and desired dtypes and shapes
     check_scalar : bool, default: False
@@ -60,8 +63,9 @@ def _check_ns_shape_dtype(
     actual_xp = array_namespace(actual)  # Raises on scalars and lists
     desired_xp = array_namespace(desired)
 
-    msg = f"namespaces do not match: {actual_xp} != f{desired_xp}"
-    assert actual_xp == desired_xp, msg
+    if check_namespace:
+        msg = f"namespaces do not match: {actual_xp} != f{desired_xp}"
+        assert actual_xp == desired_xp, msg
 
     # Dask uses nan instead of None for unknown shapes
     actual_shape = cast(tuple[float, ...], actual.shape)
@@ -139,6 +143,7 @@ def xp_assert_equal(
     desired: Array,
     *,
     err_msg: str = "",
+    check_namespace: bool = True,
     check_dtype: bool = True,
     check_shape: bool = True,
     check_scalar: bool = False,
@@ -154,6 +159,8 @@ def xp_assert_equal(
         The expected array (typically hardcoded).
     err_msg : str, optional
         Error message to display on failure.
+    check_namespace : bool, default: True
+        Whether to check agreement between actual and desired namespace.
     check_dtype, check_shape : bool, default: True
         Whether to check agreement between actual and desired dtypes and shapes
     check_scalar : bool, default: False
@@ -165,7 +172,14 @@ def xp_assert_equal(
     xp_assert_close : Similar function for inexact equality checks.
     numpy.testing.assert_array_equal : Similar function for NumPy arrays.
     """
-    xp = _check_ns_shape_dtype(actual, desired, check_dtype, check_shape, check_scalar)
+    xp = _check_ns_shape_dtype(
+        actual,
+        desired,
+        check_namespace,
+        check_dtype,
+        check_shape,
+        check_scalar,
+    )
     if not _is_materializable(actual):
         return
     actual_np = as_numpy_array(actual, xp=xp)
@@ -178,6 +192,7 @@ def xp_assert_less(
     y: Array,
     *,
     err_msg: str = "",
+    check_namespace: bool = True,
     check_dtype: bool = True,
     check_shape: bool = True,
     check_scalar: bool = False,
@@ -191,6 +206,8 @@ def xp_assert_less(
         The arrays to compare according to ``x < y`` (elementwise).
     err_msg : str, optional
         Error message to display on failure.
+    check_namespace : bool, default: True
+        Whether to check agreement between actual and desired namespace.
     check_dtype, check_shape : bool, default: True
         Whether to check agreement between actual and desired dtypes and shapes
     check_scalar : bool, default: False
@@ -202,7 +219,7 @@ def xp_assert_less(
     xp_assert_close : Similar function for inexact equality checks.
     numpy.testing.assert_array_equal : Similar function for NumPy arrays.
     """
-    xp = _check_ns_shape_dtype(x, y, check_dtype, check_shape, check_scalar)
+    xp = _check_ns_shape_dtype(x, y, check_namespace, check_dtype, check_shape, check_scalar)
     if not _is_materializable(x):
         return
     x_np = as_numpy_array(x, xp=xp)
@@ -217,6 +234,7 @@ def xp_assert_close(
     rtol: float | None = None,
     atol: float = 0,
     err_msg: str = "",
+    check_namespace: bool = True,
     check_dtype: bool = True,
     check_shape: bool = True,
     check_scalar: bool = False,
@@ -236,6 +254,8 @@ def xp_assert_close(
         Absolute tolerance. Default: 0.
     err_msg : str, optional
         Error message to display on failure.
+    check_namespace : bool, default: True
+        Whether to check agreement between actual and desired namespace.
     check_dtype, check_shape : bool, default: True
         Whether to check agreement between actual and desired dtypes and shapes
     check_scalar : bool, default: False
@@ -252,7 +272,14 @@ def xp_assert_close(
     -----
     The default `atol` and `rtol` differ from `xp.all(xpx.isclose(a, b))`.
     """
-    xp = _check_ns_shape_dtype(actual, desired, check_dtype, check_shape, check_scalar)
+    xp = _check_ns_shape_dtype(
+        actual,
+        desired,
+        check_namespace,
+        check_dtype,
+        check_shape,
+        check_scalar,
+    )
     if not _is_materializable(actual):
         return