Fix server SIGTERM handler signature

bmspy/server.py

@@ -15,6 +15,7 @@ import re
 import struct
 import serial
 from dataclasses import asdict as dataclass_asdict, dataclass
+from types import FrameType
 from typing import Any, NoReturn
 
 from bmspy.utilities import debugger
@@ -52,7 +53,7 @@ class DeviceState:
 connected_clients = list()
 
 
-def signalHandler() -> NoReturn:
+def signalHandler(signum: int, frame: FrameType | None) -> NoReturn:
     raise SystemExit("terminating")
 
 

tests/test_server.py

@@ -1,6 +1,9 @@
 import json
+import signal
 import socket as socket_module
 import struct
+import subprocess
+import sys
 import threading
 
 import pytest
@@ -166,12 +169,40 @@ class TestSignalHandler:
     def test_raises_system_exit(self):
         from bmspy.server import signalHandler
         with pytest.raises(SystemExit):
-            signalHandler()
+            signalHandler(signal.SIGTERM, None)
 
     def test_exit_message_contains_terminating(self):
         from bmspy.server import signalHandler
         with pytest.raises(SystemExit, match="terminating"):
-            signalHandler()
+            signalHandler(signal.SIGTERM, None)
+
+    def test_sigterm_during_accept_cleans_up_without_traceback(self, tmp_path):
+        socket_path = tmp_path / "bms.sock"
+        script = """
+import atexit
+import os
+import signal
+import socket
+import sys
+import threading
+from bmspy.server import signalHandler, socket_cleanup
+
+signal.signal(signal.SIGTERM, signalHandler)
+listener = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
+listener.bind(sys.argv[1])
+listener.listen(1)
+atexit.register(socket_cleanup, sys.argv[1])
+threading.Timer(0.1, os.kill, args=(os.getpid(), signal.SIGTERM)).start()
+listener.accept()
+"""
+        result = subprocess.run(
+            [sys.executable, "-c", script, str(socket_path)],
+            capture_output=True, text=True, timeout=10,
+        )
+        # Preserve the existing SystemExit("terminating") behavior.
+        assert result.returncode == 1
+        assert result.stderr.strip() == "terminating"
+        assert not socket_path.exists()
 
 
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