sqlite3: add Cursor.row_factory pygetset and fix Connection.cursor() propagation (RustPython#7278)

ever0de · web-flow · commit 8a7952f19f0b · 2026-03-01T10:44:50.000+09:00
Add #[pygetset] getter/setter for Cursor.row_factory so that Python-level
attribute access reads/writes the Rust struct field instead of the
instance dict.

Fix Connection.cursor() to only propagate the connection's row_factory
to the cursor when the connection's row_factory is not None, matching
CPython behavior. Previously it unconditionally overwrote the cursor's
row_factory, discarding any factory set by a cursor subclass __init__.
diff --git a/Lib/test/test_sqlite3/test_factory.py b/Lib/test/test_sqlite3/test_factory.py
@@ -112,7 +112,6 @@ def test_invalid_factory(self):
 
 class RowFactoryTestsBackwardsCompat(MemoryDatabaseMixin, unittest.TestCase):
 
-    @unittest.expectedFailure # TODO: RUSTPYTHON
     def test_is_produced_by_factory(self):
         cur = self.con.cursor(factory=MyCursor)
         cur.execute("select 4+5 as foo")
diff --git a/crates/stdlib/src/_sqlite3.rs b/crates/stdlib/src/_sqlite3.rs
@@ -1043,8 +1043,10 @@ mod _sqlite3 {
                 )));
             }
 
-            if let Some(cursor_ref) = cursor.downcast_ref::<Cursor>() {
-                let _ = unsafe { cursor_ref.row_factory.swap(zelf.row_factory.to_owned()) };
+            if let Some(cursor_ref) = cursor.downcast_ref::<Cursor>()
+                && let Some(factory) = zelf.row_factory.to_owned()
+            {
+                let _ = unsafe { cursor_ref.row_factory.swap(Some(factory)) };
             }
 
             Ok(cursor)
@@ -1977,6 +1979,16 @@ mod _sqlite3 {
             Ok(())
         }
 
+        #[pygetset]
+        fn row_factory(&self) -> Option<PyObjectRef> {
+            self.row_factory.to_owned()
+        }
+
+        #[pygetset(setter)]
+        fn set_row_factory(&self, val: Option<PyObjectRef>) {
+            let _ = unsafe { self.row_factory.swap(val) };
+        }
+
         fn build_row_cast_map(
             &self,
             st: &SqliteStatementRaw,
