fix: tolerate QMP socket removal during status probes

hydra/runtime.py

@@ -182,9 +182,11 @@ class Runtime:
             raise RuntimeError(f'Cannot verify VM identity: {exc}') from exc
 
     def _listening(self, path: Path) -> bool:
-        if not path.exists():
+        try:
+            mode = path.lstat().st_mode
+        except FileNotFoundError:
             return False
-        if not stat.S_ISSOCK(path.lstat().st_mode):
+        if not stat.S_ISSOCK(mode):
             raise RuntimeError(f'Refusing non-socket runtime path: {path}')
         with socket.socket(socket.AF_UNIX) as probe:
             probe.settimeout(min(1, self.boot_timeout))

tests/test_runtime.py

@@ -105,6 +105,19 @@ class RuntimeTests(unittest.TestCase):
         self.assertNotIn('-vnc', argv)
         self.assertNotIn('-virtfs', argv)
 
+    def test_socket_removed_during_stat_is_safely_not_listening(self):
+        paths = self.runtime.paths('guest')
+        paths.qmp.parent.mkdir(parents=True)
+        with socket.socket(socket.AF_UNIX) as fixture:
+            fixture.bind(str(paths.qmp))
+            original_lstat = Path.lstat
+            def disappearing_socket(path):
+                if path == paths.qmp:
+                    path.unlink(missing_ok=True)
+                return original_lstat(path)
+            with patch.object(Path, 'lstat', disappearing_socket):
+                self.assertFalse(self.runtime._listening(paths.qmp))
+
     def test_argv_provides_audio_and_manual_usb_channels(self):
         argv = build_qemu_argv(self.profile, self.runtime.paths('guest'))
         self.assertIn('spice,id=audio', argv)