Fix unifi_discovery deepcopy crash on Python 3.14 (#168153)

tests/components/unifi_discovery/__init__.py

@@ -2,6 +2,7 @@
 
 from collections.abc import Generator
 from contextlib import contextmanager
+from types import MappingProxyType
 from unittest.mock import AsyncMock, MagicMock, patch
 
 from unifi_discovery import AIOUnifiScanner, UnifiDevice, UnifiService
@@ -30,6 +31,21 @@ UNIFI_DISCOVERY_NO_MAC = UnifiDevice(
     direct_connect_domain=DIRECT_CONNECT_DOMAIN,
 )
 
+# In production the crash happens because asdict() deep-copies Enum keys in
+# the services dict, and on Python 3.14+ deepcopy traverses into
+# Enum.__members__ (a mappingproxy) which cannot be pickled.  Whether
+# deepcopy(enum) actually fails depends on the specific CPython build, so
+# we force the error reliably by using MappingProxyType directly as the
+# services value — deepcopy always fails on it.
+UNIFI_DISCOVERY_MAPPINGPROXY_SERVICES = UnifiDevice(
+    source_ip=DEVICE_IP_ADDRESS,
+    hw_addr=DEVICE_MAC_ADDRESS,
+    platform=DEVICE_HOSTNAME,
+    hostname=DEVICE_HOSTNAME,
+    services=MappingProxyType({UnifiService.Protect: True}),
+    direct_connect_domain=DIRECT_CONNECT_DOMAIN,
+)
+
 
 def _patch_discovery(
     device: UnifiDevice | None = None, no_device: bool = False

tests/components/unifi_discovery/test_init.py

@@ -7,7 +7,11 @@ from homeassistant.components.unifi_discovery.const import DOMAIN
 from homeassistant.core import HomeAssistant
 from homeassistant.setup import async_setup_component
 
-from . import UNIFI_DISCOVERY_NO_MAC, _patch_discovery
+from . import (
+    UNIFI_DISCOVERY_MAPPINGPROXY_SERVICES,
+    UNIFI_DISCOVERY_NO_MAC,
+    _patch_discovery,
+)
 
 
 async def test_setup_starts_discovery(hass: HomeAssistant) -> None:
@@ -54,3 +58,20 @@ async def test_dependency_loads_discovery(
     flows = hass.config_entries.flow.async_progress_by_handler("unifiprotect")
     assert len(flows) == 1
     assert flows[0]["context"]["source"] == config_entries.SOURCE_INTEGRATION_DISCOVERY
+
+
+async def test_discovery_does_not_deepcopy_device(hass: HomeAssistant) -> None:
+    """Test discovery works without deepcopy.
+
+    In production asdict() deep-copies Enum keys in the services dict which
+    can crash on Python 3.14+ because Enum.__members__ is a mappingproxy that
+    cannot be pickled.  We force the crash reliably by using MappingProxyType
+    as the services value.
+    """
+    with _patch_discovery(device=UNIFI_DISCOVERY_MAPPINGPROXY_SERVICES):
+        assert await async_setup_component(hass, DOMAIN, {})
+        await hass.async_block_till_done(wait_background_tasks=True)
+
+    flows = hass.config_entries.flow.async_progress_by_handler("unifiprotect")
+    assert len(flows) == 1
+    assert flows[0]["context"]["source"] == config_entries.SOURCE_INTEGRATION_DISCOVERY