test: tolerate missing mempool xfail helper

Allow cuda_core tests to run against older cuda.bindings artifacts by falling back when the mempool xfail helper is unavailable, so collection succeeds without the new OOM xfail behavior.

Co-authored-by: Cursor <cursoragent@cursor.com>

Author: rwgk

cuda_core/tests/conftest.py

@@ -17,7 +17,6 @@
     from cuda import cuda as driver
 
 import cuda.core
-from cuda.bindings._test_helpers.mempool import xfail_if_mempool_oom
 from cuda.core import (
     Device,
     DeviceMemoryResource,
@@ -30,6 +29,16 @@
 )
 from cuda.core._utils.cuda_utils import CUDAError, handle_return
 
+try:
+    from cuda.bindings._test_helpers.mempool import xfail_if_mempool_oom
+except ModuleNotFoundError:
+    # Older cuda.bindings artifacts (for example 12.9.x backports) do not ship
+    # this helper yet. In that case, keep the primary failure visible instead of
+    # xfail-ing the known Windows MCDM mempool setup issue.
+    def xfail_if_mempool_oom(err_or_exc, api_name=None, device=0):
+        return
+
+
 # Import shared test helpers for tests across subprojects.
 # PLEASE KEEP IN SYNC with copies in other conftest.py in this repo.
 _test_helpers_root = pathlib.Path(__file__).resolve().parents[2] / "cuda_python_test_helpers"

cuda_core/tests/test_managed_memory_warning.py

@@ -13,7 +13,7 @@
 import pytest
 
 import cuda.bindings
-from cuda.bindings._test_helpers.mempool import xfail_if_mempool_oom
+from conftest import xfail_if_mempool_oom
 from cuda.core import Device, ManagedMemoryResource, ManagedMemoryResourceOptions
 from cuda.core._memory._managed_memory_resource import reset_concurrent_access_warning
 from cuda.core._utils.cuda_utils import CUDAError