Fix Unix remote watchdog socket leak

tests/unit/test_unix_remote_driver.py

@@ -1,5 +1,7 @@
 from unittest.mock import Mock, mock_open, patch
 
+import pytest
+
 from fenrirscreenreader.remoteDriver import unixDriver
 
 
@@ -27,6 +29,40 @@ def test_watchdog_keeps_serving_when_instance_registration_fails(
     select_call.assert_called_once()
 
 
+def test_watchdog_closes_listeners_when_unexpected_error_escapes(
+    mock_environment,
+):
+    driver = unixDriver.driver()
+    driver.env = mock_environment
+    listener = Mock()
+    active = Mock(value=True)
+
+    with patch.object(
+        driver,
+        "_get_socket_candidates",
+        return_value=[("/tmp/fenrir-test.sock", False)],
+    ), patch.object(
+        driver, "_bind_socket", return_value=listener
+    ), patch.object(
+        driver, "_try_register_instance"
+    ), patch(
+        "fenrirscreenreader.remoteDriver.unixDriver.select.select",
+        side_effect=RuntimeError("unexpected failure"),
+    ), patch(
+        "fenrirscreenreader.remoteDriver.unixDriver.os.path.exists",
+        return_value=False,
+    ), patch(
+        "fenrirscreenreader.remoteDriver.unixDriver.remoteInstanceRegistry.remove_instance"
+    ) as remove_instance:
+        with pytest.raises(RuntimeError, match="unexpected failure"):
+            driver.watch_dog(active, Mock())
+
+    listener.close.assert_called_once_with()
+    assert driver.fenrirSocks == []
+    assert driver.bound_sockets == []
+    remove_instance.assert_called_once_with()
+
+
 class FakeClientSocket:
     def __init__(self, data):
         self.data = data