Add a test that confirms __getattr__ doesn't override

tests/test_dunder.rs

@@ -462,3 +462,25 @@ fn weakref_dunder_dict_support() {
         "import weakref; assert weakref.ref(inst)() is inst; inst.a = 1; assert inst.a == 1"
     );
 }
+
+#[pyclass]
+struct ClassWithGetAttr {
+    #[pyo3(get, set)]
+    data: u32,
+}
+
+#[pyproto]
+impl PyObjectProtocol for ClassWithGetAttr {
+    fn __getattr__(&self, _name: &str) -> PyResult<u32> {
+        Ok(self.data * 2)
+    }
+}
+
+#[test]
+fn getattr_doesnt_override_member() {
+    let gil = Python::acquire_gil();
+    let py = gil.python();
+    let inst = PyRef::new(py, ClassWithGetAttr { data: 4 }).unwrap();
+    py_assert!(py, inst, "inst.data == 4");
+    py_assert!(py, inst, "inst.a == 8");
+}