From 81bf0fef2e2fb13574611f524aaaa15933853b1d Mon Sep 17 00:00:00 2001
From: Sven Delmas <sven@ignoranceisbliss.com>
Date: Thu, 10 Sep 2026 03:37:48 -0600
Subject: [PATCH] Report UniFi WAN latency as unknown when a monitor is
 unresponsive (#181809)

Co-authored-by: Claude Opus 5 (1M context) <noreply@anthropic.com>
Co-authored-by: Ariel Ebersberger <ariel@ebersberger.io>
---
 homeassistant/components/unifi/sensor.py      |  2 +-
 .../unifi/snapshots/test_sensor.ambr          |  6 +--
 tests/components/unifi/test_sensor.py         | 37 ++++++++++++-------
 3 files changed, 27 insertions(+), 18 deletions(-)

diff --git a/homeassistant/components/unifi/sensor.py b/homeassistant/components/unifi/sensor.py
index cf10b61d0578..0d6671ba78dc 100644
--- a/homeassistant/components/unifi/sensor.py
+++ b/homeassistant/components/unifi/sensor.py
@@ -263,7 +263,7 @@ def async_device_wan_latency_value_fn(
         # Checked by async_device_wan_latency_supported_fn
         assert target
 
-    return target.get("latency_average", 0)
+    return target.get("latency_average")
 
 
 @callback
diff --git a/tests/components/unifi/snapshots/test_sensor.ambr b/tests/components/unifi/snapshots/test_sensor.ambr
index efc258d9be8a..e493f9a7dd2b 100644
--- a/tests/components/unifi/snapshots/test_sensor.ambr
+++ b/tests/components/unifi/snapshots/test_sensor.ambr
@@ -812,7 +812,7 @@
     'last_changed': <ANY>,
     'last_reported': <ANY>,
     'last_updated': <ANY>,
-    'state': '0',
+    'state': 'unknown',
   })
 # ---
 # name: test_entity_and_device_data[wlan_payload0-device_payload0-client_payload0-config_entry_options0][sensor.mock_name_cloudflare_wan_latency-entry]
@@ -928,7 +928,7 @@
     'last_changed': <ANY>,
     'last_reported': <ANY>,
     'last_updated': <ANY>,
-    'state': '0',
+    'state': 'unknown',
   })
 # ---
 # name: test_entity_and_device_data[wlan_payload0-device_payload0-client_payload0-config_entry_options0][sensor.mock_name_google_wan_latency-entry]
@@ -1044,7 +1044,7 @@
     'last_changed': <ANY>,
     'last_reported': <ANY>,
     'last_updated': <ANY>,
-    'state': '0',
+    'state': 'unknown',
   })
 # ---
 # name: test_entity_and_device_data[wlan_payload0-device_payload0-client_payload0-config_entry_options0][sensor.mock_name_microsoft_wan_latency-entry]
diff --git a/tests/components/unifi/test_sensor.py b/tests/components/unifi/test_sensor.py
index bf346b4b12d3..80e65b8651f9 100644
--- a/tests/components/unifi/test_sensor.py
+++ b/tests/components/unifi/test_sensor.py
@@ -1710,14 +1710,22 @@ async def test_device_uptime(
     ],
 )
 @pytest.mark.parametrize(
-    ("monitor_id", "state", "updated_state", "index_to_update"),
+    ("monitor_id", "state", "index_to_update", "monitor_update", "updated_state"),
     [
-        # Microsoft
-        ("microsoft_wan", "56", "20", 0),
-        # Google
-        ("google_wan", "53", "90", 1),
-        # Cloudflare
-        ("cloudflare_wan", "30", "80", 2),
+        pytest.param(
+            "microsoft_wan", "56", 0, {"latency_average": 20}, "20", id="microsoft"
+        ),
+        pytest.param("google_wan", "53", 1, {"latency_average": 90}, "90", id="google"),
+        pytest.param(
+            "cloudflare_wan", "30", 2, {"latency_average": 80}, "80", id="cloudflare"
+        ),
+        pytest.param(
+            "microsoft_wan", "56", 0, {}, STATE_UNKNOWN, id="microsoft_no_response"
+        ),
+        pytest.param("google_wan", "53", 1, {}, STATE_UNKNOWN, id="google_no_response"),
+        pytest.param(
+            "cloudflare_wan", "30", 2, {}, STATE_UNKNOWN, id="cloudflare_no_response"
+        ),
     ],
 )
 @pytest.mark.usefixtures("config_entry_setup")
@@ -1728,8 +1736,9 @@ async def test_wan_monitor_latency(
     device_payload: list[dict[str, Any]],
     monitor_id: str,
     state: str,
-    updated_state: str,
     index_to_update: int,
+    monitor_update: dict[str, Any],
+    updated_state: str,
 ) -> None:
     """Verify that wan latency sensors are working as expected."""
     entity_id = f"sensor.mock_name_{monitor_id}_latency"
@@ -1757,14 +1766,14 @@ async def test_wan_monitor_latency(
     # Verify sensor state
     assert hass.states.get(entity_id).state == state
 
-    # Verify state update
-    device = device_payload[0]
-    device["uptime_stats"]["WAN"]["monitors"][index_to_update]["latency_average"] = (
-        updated_state
-    )
-
+    # Update state
+    device = deepcopy(device_payload[0])
+    monitor = device["uptime_stats"]["WAN"]["monitors"][index_to_update]
+    monitor.pop("latency_average")
+    monitor.update(monitor_update)
     mock_websocket_message(message=MessageKey.DEVICE, data=device)
 
+    # Verify state update
     assert hass.states.get(entity_id).state == updated_state