From a12aef2a8ce39b7d85c28033bd7eff0d1e60b1da Mon Sep 17 00:00:00 2001
From: adenzhou1350 <aden1350@outlook.com>
Date: Fri, 23 Oct 2026 02:44:48 +0800
Subject: [PATCH] fix: return a Python error when querying a closed table
 (#4455)

`AsyncTable.query()` unwraps the native closed-table error, so querying
a closed table raises `PanicException` instead of the documented
`RuntimeError`. `AsyncTable.head()` reaches the same path.

Propagate `inner_ref()`'s error through `PyResult` instead. Add
regressions for closed `query()` and `head()`, with `count_rows()`,
repeated close, and normal open-table queries as controls.

Validation against separately built native bindings:

- Before: 2 regression failures (`PanicException`), 2 controls passed.
- After: all 4 regressions passed.
- Existing query tests plus the basic database test: 102 passed, 1
skipped on each arm (Torch is not installed).
- `cargo fmt --all -- --check`, Ruff, and `git diff --check` passed.

The native build used the locked Cargo dependencies with
`remote,lancedb/metrics-otel,pyo3/extension-module`. This is source-tree
native testing, not a complete wheel-packaging or cloud-service test.

Signed-off-by: Xucheng Zhou <aden1350@outlook.com>
---
 .../python/tests/test_closed_table_query.py   | 32 +++++++++++++++++++
 python/src/table.rs                           |  4 +--
 2 files changed, 34 insertions(+), 2 deletions(-)
 create mode 100644 python/python/tests/test_closed_table_query.py

diff --git a/python/python/tests/test_closed_table_query.py b/python/python/tests/test_closed_table_query.py
new file mode 100644
index 000000000..2ff3a8e98
--- /dev/null
+++ b/python/python/tests/test_closed_table_query.py
@@ -0,0 +1,32 @@
+# SPDX-License-Identifier: Apache-2.0
+# SPDX-FileCopyrightText: Copyright The LanceDB Authors
+
+import pytest
+from lancedb.db import AsyncConnection
+
+
+@pytest.mark.asyncio
+@pytest.mark.parametrize("operation", ["count_rows", "query", "head"])
+async def test_closed_table_queries_raise_runtime_error(
+    mem_db_async: AsyncConnection, operation
+):
+    table = await mem_db_async.create_table("closed_query", data=[{"id": 0}])
+    assert (await table.query().to_arrow()).to_pylist() == [{"id": 0}]
+    table.close()
+    table.close()
+    assert not table.is_open()
+
+    with pytest.raises(RuntimeError, match="Table closed_query is closed"):
+        if operation == "query":
+            table.query()
+        else:
+            await getattr(table, operation)()
+
+
+@pytest.mark.asyncio
+async def test_open_table_queries(mem_db_async: AsyncConnection):
+    table = await mem_db_async.create_table("open_query", data=[{"id": 0}])
+    assert await table.count_rows() == 1
+    assert (await table.query().to_arrow()).to_pylist() == [{"id": 0}]
+    assert (await table.head()).to_pylist() == [{"id": 0}]
+    table.close()
diff --git a/python/src/table.rs b/python/src/table.rs
index c1d23d151..27ed8be8b 100644
--- a/python/src/table.rs
+++ b/python/src/table.rs
@@ -1428,8 +1428,8 @@ impl Table {
         })
     }
 
-    pub fn query(&self) -> Query {
-        Query::new(self.inner_ref().unwrap().query())
+    pub fn query(&self) -> PyResult<Query> {
+        Ok(Query::new(self.inner_ref()?.query()))
     }
 
     #[getter]