gh-152817: Prevent deletion of sqlite3 cursor.row_factory attr, missed from: gh-149738 (GH-152818)

Author: stestagg

Lib/test/test_sqlite3/test_factory.py

@@ -156,6 +156,14 @@ def test_delete_connection_text_factory(self):
         with self.assertRaises(AttributeError):
             del self.con.text_factory
 
+    def test_delete_cursor_row_factory(self):
+        # gh-149738: deleting row_factory should raise an exception
+        cur = self.con.cursor()
+        with self.assertRaises(AttributeError):
+            del cur.row_factory
+        # Executing a query here should succeed.
+        self.assertEqual(tuple(cur.execute("select 1").fetchone()), (1,))
+
     def test_sqlite_row_index_unicode(self):
         row = self.con.execute("select 1 as \xff").fetchone()
         self.assertEqual(row["\xff"], 1)

Misc/NEWS.d/next/Core_and_Builtins/2026-05-13-06-54-41.gh-issue-149738.4BLFoH.rst

@@ -1,2 +1,2 @@
 :mod:`sqlite3`: Disallow removing ``row_factory`` and ``text_factory`` attributes
-of a connection to prevent a crash on a query.
+of a connection or cursor to prevent a crash on a query.

Modules/_sqlite/cursor.c

@@ -1405,13 +1405,33 @@ static struct PyMemberDef cursor_members[] =
     {"description", _Py_T_OBJECT, offsetof(pysqlite_Cursor, description), Py_READONLY},
     {"lastrowid", _Py_T_OBJECT, offsetof(pysqlite_Cursor, lastrowid), Py_READONLY},
     {"rowcount", Py_T_LONG, offsetof(pysqlite_Cursor, rowcount), Py_READONLY},
-    {"row_factory", _Py_T_OBJECT, offsetof(pysqlite_Cursor, row_factory), 0},
     {"__weaklistoffset__", Py_T_PYSSIZET, offsetof(pysqlite_Cursor, in_weakreflist), Py_READONLY},
     {NULL}
 };
 
+static PyObject *
+cursor_get_row_factory(PyObject *op, void *Py_UNUSED(closure))
+{
+    pysqlite_Cursor *self = _pysqlite_Cursor_CAST(op);
+    return Py_NewRef(self->row_factory);
+}
+
+static int
+cursor_set_row_factory(PyObject *op, PyObject *value, void *Py_UNUSED(closure))
+{
+    pysqlite_Cursor *self = _pysqlite_Cursor_CAST(op);
+    if (value == NULL) {
+        PyErr_SetString(PyExc_AttributeError,
+                        "cannot delete row_factory attribute");
+        return -1;
+    }
+    Py_XSETREF(self->row_factory, Py_NewRef(value));
+    return 0;
+}
+
 static struct PyGetSetDef cursor_getsets[] = {
     _SQLITE3_CURSOR_ARRAYSIZE_GETSETDEF
+    {"row_factory", cursor_get_row_factory, cursor_set_row_factory},
     {NULL},
 };