fix: _empty_message should be an attribute or property not a function

Author: FlysonBot

src/mastermind/ui/menu/data_menu.py

@@ -1,10 +1,10 @@
-from abc import abstractmethod
+from abc import ABC, abstractmethod
 from typing import Any, Optional
 
 from mastermind.ui.menu.base_menu import BaseMenu
 
 
-class DataDisplayMenu(BaseMenu):
+class DataDisplayMenu(BaseMenu, ABC):
     """
     An abstract base class for menus that display data.
 
@@ -19,7 +19,7 @@ def _print_content(self) -> None:
         if data is not None:
             self._render_data(data)
         else:
-            print(self._empty_message())
+            print(self._empty_message)
 
     @abstractmethod
     def _fetch_data(self) -> Optional[Any]:

src/mastermind/ui/menu/game_history_menu.py

@@ -14,6 +14,7 @@ class GameHistoryMenu(DataDisplayMenu):
 
     name = "Game History"
     width = 25
+    _empty_message = "No game history found."
 
     def _fetch_data(self) -> Optional[pd.DataFrame]:
         """
@@ -27,12 +28,6 @@ def _render_data(self, data: pd.DataFrame) -> None:
         """
         render_dataframe(data)
 
-    def _empty_message(self) -> str:
-        """
-        Returns the message to display when there is no game history.
-        """
-        return "No game history found."
-
     def display(self) -> None:
         """
         Displays the game history menu and waits for user input to continue.

tests/ui/menu/test_data_menu.py

@@ -10,7 +10,7 @@ class ConcreteDataDisplayMenu(DataDisplayMenu):
         name = "Data Menu"
         _fetch_data = None
         _render_data = None
-        _empty_message = None
+        _empty_message = "No data available"
 
     def setUp(self):
         self.data_menu = self.ConcreteDataDisplayMenu()
@@ -26,11 +26,8 @@ def test_print_content_with_data(self, mock_render_data, mock_fetch_data):
 
     @patch.object(ConcreteDataDisplayMenu, "_fetch_data", return_value=None)
     @patch.object(ConcreteDataDisplayMenu, "_render_data")
-    @patch.object(
-        ConcreteDataDisplayMenu, "_empty_message", return_value="No data available"
-    )
     def test_print_content_without_data(
-        self, mock_empty_message, mock_render_data, mock_fetch_data
+        self, mock_render_data, mock_fetch_data
     ):
         with patch("builtins.print") as mock_print:
             self.data_menu._print_content()