fix: tilecpp exported unconditionally despite conditional import

[andrewwhitecdw]

This PR addresses the following issue in src/tilegym/ops/__init__.py: tilecpp exported unconditionally despite conditional import.

Changes

• src/tilegym/ops/__init__.py: tilecpp exported unconditionally despite conditional import.

Details

--- a/src/tilegym/ops/__init__.py
+++ b/src/tilegym/ops/__init__.py
@@ -1,39 +1,49 @@
-# Import CUDA Tile C++ backend if available
-if is_backend_available("tilecpp"):
-    from . import tilecpp
-
-# Re-export key interfaces
-from .attn_interface import attention_sink_interface
-from .attn_interface import fmha_interface
-from .attn_interface import get_attention_sink_interface
-from .attn_interface import get_fmha_gemma3_interface
-from .attn_interface import get_fmha_interface
-from .attn_interface import mla_decoding_interface
-from .attn_interface import mla_interface
-from .moe_interface import fused_moe
-
-# Import all operation interfaces from the unified ops module
-from .ops import *
-
-__all__ = [
-    # Export all operations from ops module
-    # Backend implementations
-    "tilecpp",
-    # Interface modules
-    "attn_interface",
-    "moe_interface",
-    # Re-exported submodules
-    # Key interfaces
-    "attention_sink_interface",
-    "fmha_interface",
-    "get_attention_sink_interface",
-    "get_fmha_interface",
-    "get_fmha_gemma3_interface",
-    "mla_interface",
-    "mla_decoding_interface",
-    "fused_moe",
-]
-
-# Add cutile to exports only if successfully imported
-if cutile is not None:
-    __all__.append("cutile")
+# Import CUDA Tile C++ backend if available
+tilecpp = None  # type: ignore
+if is_backend_available("tilecpp"):
+    try:
+        from . import tilecpp
+    except (ImportError, RuntimeError):
+        import warnings
+
+        warnings.warn(
+            "tilecpp backend import failed, tilecpp operations will not be available"
+        )
+        tilecpp = None  # type: ignore
+
+# Re-export key interfaces
+from .attn_interface import attention_sink_interface
+from .attn_interface import fmha_interface
+from .attn_interface import get_attention_sink_interface
+from .attn_interface import get_fmha_gemma3_interface
+from .attn_interface import get_fmha_interface
+from .attn_interface import mla_decoding_interface
+from .attn_interface import mla_interface
+from .moe_interface import fused_moe
+
+# Import all operation interfaces from the unified ops module
+from .ops import *
+
+__all__ = [
+    # Export all operations from ops module
+    # Backend implementations
+    # Interface modules
+    "attn_interface",
+    "moe_interface",
+    # Re-exported submodules
+    # Key interfaces
+    "attention_sink_interface",
+    "fmha_interface",
+    "get_attention_sink_interface",
+    "get_fmha_interface",
+    "get_fmha_gemma3_interface",
+    "mla_interface",
+    "mla_decoding_interface",
+    "fused_moe",
+]
+
+# Add backend submodules to exports only if successfully imported
+if cutile is not None:
+    __all__.append("cutile")
+if tilecpp is not None:
+    __all__.append("tilecpp")

Tests

• tests/test_ops_init.py

--- /dev/null
+++ b/tests/test_ops_init.py
@@ -0,0 +1,11 @@
+"""Tests for the tilegym.ops package init."""
+
+
+def test_tilecpp_not_exported_when_unavailable():
+    """If tilecpp is not imported, it must not appear in __all__."""
+    import tilegym.ops as ops
+
+    if not hasattr(ops, "tilecpp") or ops.tilecpp is None:
+        assert "tilecpp" not in ops.__all__
+
+
+def test_star_import_does_not_raise():
+    """`from tilegym.ops import *` must always succeed."""
+    import tilegym.ops as ops
+
+    # Exercise __all__ by performing a star import in a fresh namespace.
+    namespace = {"__name__": "test_ops_init"}
+    exec("from tilegym.ops import *", namespace)
+    for name in ops.__all__:
+        assert name in namespace

Contributor guidelines

Per this repo's CONTRIBUTING.md:

• All commits are signed off (Signed-off-by trailer, DCO).

CI Configuration

config:
  build: true
  # valid options are "ops" and "benchmark"
  test: ["ops", "benchmark"]

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[hannahli-nv]

Hi @andrewwhitecdw, thanks for the fix!

Two small asks before we can merge:

1. Could you please drop tests/test_ops_init.py? The current test layout doesn't really need a dedicated test for this guard.

2. Since it's your first time to contribute codes, we'll need a signed CLA file. Per first-time-contributors-cla-required, contributions to the skills/ directory only need a DCO sign-off, but changes elsewhere are MIT-licensed and require a signed CLA (LICENSES/CLA.md) emailed to TileGym@nvidia.com. Thanks for understanding!

[hannahli-nv]

/ok to test 633189e