chore[py]: duckdb py test for timestamp xfail

vortex-python/test/test_duckdb.py

@@ -0,0 +1,27 @@
+# SPDX-License-Identifier: Apache-2.0
+# SPDX-FileCopyrightText: Copyright the Vortex contributors
+
+"""Test for timestamp filtering with DuckDB via vortex extension and PyArrow dataset interface."""
+
+from datetime import datetime
+from pathlib import Path
+
+import duckdb
+import pyarrow as pa
+import pytest
+
+import vortex as vx
+
+
+@pytest.mark.xfail(reason="is_not_null not yet implemented in substrait conversion")
+def test_duckdb_via_substrait(tmp_path: Path) -> None:
+    con = duckdb.connect()
+
+    arr = pa.array([datetime(2024, 1, 1), datetime(2024, 6, 15), datetime(2024, 12, 31)])
+    table = pa.table({"ts": arr})
+    path = str(tmp_path / "test_timestamp.vortex")
+    vx.io.write(table, path)
+
+    ds = vx.open(path).to_dataset()  # noqa: F841  # pyright: ignore[reportUnusedVariable] - used by duckdb via SQL
+    result = con.execute("SELECT * FROM ds WHERE ts > '2024-06-01'").fetchall()
+    print(result)