Address duplicate import issue found in pypi-installed cuda-core packages

cuda_core/tests/test_duplicate_imports.py

@@ -0,0 +1,32 @@
+# SPDX-FileCopyrightText: Copyright (c) 2026 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+#
+# SPDX-License-Identifier: Apache-2.0
+
+"""Tests cuda.core.__init__.py does not import duplicate modules."""
+
+import sys
+from importlib.metadata import distribution
+
+import pytest
+
+from cuda import bindings
+
+# Issue only appears when cuda/core/cu<cuda_major> directory is present in
+# site-packages; skip when 'cuda.core.cu<cuda_major>' is not found
+cuda_major = bindings.__version__.split(".")[0]
+pip_submodule = f"cuda.core.{cuda_major}"
+dist = distribution("cuda-core")
+
+if not dist.locate_file(f"cuda/core/cu{cuda_major}"):
+    pytest.skip(f"{pip_submodule} not present", allow_module_level=True)
+
+
+def test_typing_module_imports():
+    """
+    Importing cuda.core.system should not also import cuda.core.cuXX.system
+    """
+    import cuda.core
+    import cuda.core.system  # NOQA
+
+    assert "cuda.core.system" in sys.modules
+    assert f"cuda.core.cu{cuda_major}" not in sys.modules