Add save directory helpers for IF sessions

src/mudlib/if_session.py

@@ -25,6 +25,17 @@ class IFSession:
         self.story_path = story_path
         self.game_name = game_name or Path(story_path).stem
         self.process: asyncio.subprocess.Process | None = None
+        # data/ directory is at project root (2 levels up from src/mudlib/)
+        self._data_dir = Path(__file__).resolve().parents[2] / "data"
+
+    @property
+    def save_path(self) -> Path:
+        """Return path to save file for this player/game combo."""
+        return self._data_dir / "if_saves" / self.player.name / f"{self.game_name}.qzl"
+
+    def _ensure_save_dir(self) -> None:
+        """Create save directory if it doesn't exist."""
+        self.save_path.parent.mkdir(parents=True, exist_ok=True)
 
     async def start(self) -> str:
         """Spawn dfrotz and return intro text."""

tests/test_if_session.py

@@ -290,3 +290,37 @@ async def test_handle_input_empty_string():
 
     # Should still write a newline
     mock_process.stdin.write.assert_called()
+
+
+def test_save_path_property(tmp_path):
+    """save_path returns correct path for player/game combo."""
+    player = MagicMock()
+    player.name = "tester"
+    session = IFSession(player, "/path/to/zork.z5", "zork")
+
+    # Override data_dir for testing
+    session._data_dir = tmp_path
+
+    save_path = session.save_path
+    assert save_path == tmp_path / "if_saves" / "tester" / "zork.qzl"
+
+
+def test_ensure_save_dir_creates_directories(tmp_path):
+    """_ensure_save_dir() creates parent directories."""
+    player = MagicMock()
+    player.name = "alice"
+    session = IFSession(player, "/path/to/story.z5", "story")
+
+    # Override data_dir for testing
+    session._data_dir = tmp_path
+
+    # Directory shouldn't exist yet
+    expected_dir = tmp_path / "if_saves" / "alice"
+    assert not expected_dir.exists()
+
+    # Call _ensure_save_dir
+    session._ensure_save_dir()
+
+    # Now it should exist
+    assert expected_dir.exists()
+    assert expected_dir.is_dir()