add test case for subclass overriding field from parent class using t…

…o_item()

tests/test_fields.py

@@ -340,6 +340,19 @@ def field3(self):
     assert get_fields_dict(Page2)["field3"].meta == {"foo": "bar"}
     assert list(get_fields_dict(Page2)) == ["field1", "field3", "field2"]
 
+    class PageToItem(ItemPage):
+        def to_item(self):
+            return {"field1": 1, "field2": 2, "field3": 3, "field4": 4}
+
+    class Page4(PageToItem):
+        @field
+        def field4(self):
+            return 0
+
+    page_4 = Page4()
+    assert page_4.field4 == 0
+    assert page_4.to_item() == {"field1": 1, "field2": 2, "field3": 3, "field4": 0}
+
 
 def test_field_with_other_decorators() -> None:
     def clean_str(method):