Fix mypy errors

src/reachy_mini_conversation_demo/openai_realtime.py

@@ -238,14 +238,14 @@ class OpenaiRealtimeHandler(AsyncStreamHandler):
             await self.connection.close()
             self.connection = None
 
-    def format_timestamp(self):
+    def format_timestamp(self) -> str:
         """Format current timestamp with date, time, and elapsed seconds."""
         loop_time = asyncio.get_event_loop().time()  # monotonic
         elapsed_seconds = loop_time - self.start_time
         dt = datetime.now()  # wall-clock
         return f"[{dt.strftime('%Y-%m-%d %H:%M:%S')} | +{elapsed_seconds:.1f}s]"
 
-    async def send_idle_signal(self, idle_duration) -> None:
+    async def send_idle_signal(self, idle_duration: float) -> None:
         """Send an idle signal to the openai server."""
         logger.debug("Sending idle signal")
         self.is_idle_tool_call = True

tests/test_openai_realtime.py

@@ -1,18 +1,18 @@
 import asyncio
-from datetime import datetime
+from datetime import datetime, timezone
 from unittest.mock import MagicMock
 
 from reachy_mini_conversation_demo.tools import ToolDependencies
 from reachy_mini_conversation_demo.openai_realtime import OpenaiRealtimeHandler
 
 
-def _build_handler(loop):
+def _build_handler(loop: asyncio.AbstractEventLoop) -> OpenaiRealtimeHandler:
     asyncio.set_event_loop(loop)
     deps = ToolDependencies(reachy_mini=MagicMock(), movement_manager=MagicMock())
     return OpenaiRealtimeHandler(deps)
 
 
-def test_format_timestamp_uses_wall_clock():
+def test_format_timestamp_uses_wall_clock() -> None:
     """Test that format_timestamp uses wall clock time."""
     loop = asyncio.new_event_loop()
     try:
@@ -26,4 +26,4 @@ def test_format_timestamp_uses_wall_clock():
 
     # Extract year from "[YYYY-MM-DD ...]"
     year = int(formatted[1:5])
-    assert year == datetime.utcnow().year
+    assert year == datetime.now(timezone.utc).year