Add save functionality to IF sessions

src/mudlib/if_session.py

@@ -85,6 +85,30 @@ class IFSession:
             self.process.terminate()
             await self.process.wait()
 
+    async def _do_save(self) -> str:
+        """Save game state to disk. Returns confirmation message."""
+        if not self.process or not self.process.stdin:
+            return "error: game not running"
+
+        # Ensure save directory exists
+        self._ensure_save_dir()
+
+        # Send "save" command to dfrotz
+        self.process.stdin.write(b"save\n")
+        await self.process.stdin.drain()
+
+        # Read filename prompt
+        await self._read_response()
+
+        # Send save file path
+        save_path_str = str(self.save_path)
+        self.process.stdin.write(f"{save_path_str}\n".encode())
+        await self.process.stdin.drain()
+
+        # Read confirmation
+        confirmation = await self._read_response()
+        return confirmation
+
     async def _read_response(self) -> str:
         """Read dfrotz output until the '>' prompt appears."""
         if not self.process or not self.process.stdout:

tests/test_if_session.py

@@ -324,3 +324,89 @@ def test_ensure_save_dir_creates_directories(tmp_path):
     # Now it should exist
     assert expected_dir.exists()
     assert expected_dir.is_dir()
+
+
+@pytest.mark.asyncio
+async def test_do_save_sends_save_command(tmp_path):
+    """_do_save() sends save command and filepath to dfrotz."""
+    player = MagicMock()
+    player.name = "tester"
+    session = IFSession(player, "/path/to/zork.z5", "zork")
+    session._data_dir = tmp_path
+
+    # Mock process
+    mock_process = MagicMock()
+    mock_process.stdin = MagicMock()
+    mock_process.stdin.write = MagicMock()
+    mock_process.stdin.drain = AsyncMock()
+    mock_process.stdout = AsyncMock()
+    session.process = mock_process
+
+    # Simulate dfrotz responses: first the filename prompt, then confirmation
+    responses = [
+        b"Enter saved game to store: \n>",
+        b"Ok.\n>",
+    ]
+    response_data = b"".join(responses)
+
+    async def read_side_effect(n):
+        nonlocal response_data
+        if response_data:
+            byte = response_data[:1]
+            response_data = response_data[1:]
+            return byte
+        return b""
+
+    mock_process.stdout.read = AsyncMock(side_effect=read_side_effect)
+
+    result = await session._do_save()
+
+    # Should have written "save\n" then the filepath
+    calls = mock_process.stdin.write.call_args_list
+    assert len(calls) == 2
+    assert calls[0][0][0] == b"save\n"
+    assert str(session.save_path) in calls[1][0][0].decode()
+    assert b"\n" in calls[1][0][0]
+
+    # Result should contain confirmation
+    assert "Ok" in result or "ok" in result.lower()
+
+
+@pytest.mark.asyncio
+async def test_do_save_creates_save_directory(tmp_path):
+    """_do_save() ensures save directory exists."""
+    player = MagicMock()
+    player.name = "alice"
+    session = IFSession(player, "/path/to/story.z5", "story")
+    session._data_dir = tmp_path
+
+    # Mock process
+    mock_process = MagicMock()
+    mock_process.stdin = MagicMock()
+    mock_process.stdin.write = MagicMock()
+    mock_process.stdin.drain = AsyncMock()
+    mock_process.stdout = AsyncMock()
+    session.process = mock_process
+
+    # Simulate dfrotz responses
+    responses = [b"Enter saved game: \n>", b"Ok.\n>"]
+    response_data = b"".join(responses)
+
+    async def read_side_effect(n):
+        nonlocal response_data
+        if response_data:
+            byte = response_data[:1]
+            response_data = response_data[1:]
+            return byte
+        return b""
+
+    mock_process.stdout.read = AsyncMock(side_effect=read_side_effect)
+
+    # Directory shouldn't exist yet
+    expected_dir = tmp_path / "if_saves" / "alice"
+    assert not expected_dir.exists()
+
+    await session._do_save()
+
+    # Now it should exist
+    assert expected_dir.exists()