Add diagnostics for Tradfri platform (#66092)

Co-authored-by: Martin Hjelmare <marhje52@gmail.com>

homeassistant/components/tradfri/diagnostics.py

@@ -0,0 +1,36 @@
+"""Diagnostics support for IKEA Tradfri."""
+from __future__ import annotations
+
+from typing import cast
+
+from homeassistant.config_entries import ConfigEntry
+from homeassistant.core import HomeAssistant
+from homeassistant.helpers import device_registry as dr
+
+from .const import CONF_GATEWAY_ID, COORDINATOR, COORDINATOR_LIST, DOMAIN, GROUPS_LIST
+
+
+async def async_get_config_entry_diagnostics(
+    hass: HomeAssistant, entry: ConfigEntry
+) -> dict:
+    """Return diagnostics the Tradfri platform."""
+    entry_data = hass.data[DOMAIN][entry.entry_id]
+    coordinator_data = entry_data[COORDINATOR]
+
+    device_registry = dr.async_get(hass)
+    device = cast(
+        dr.DeviceEntry,
+        device_registry.async_get_device(
+            identifiers={(DOMAIN, entry.data[CONF_GATEWAY_ID])}
+        ),
+    )
+
+    device_data: list = []
+    for coordinator in coordinator_data[COORDINATOR_LIST]:
+        device_data.append(coordinator.device.device_info.model_number)
+
+    return {
+        "gateway_version": device.sw_version,
+        "device_data": sorted(device_data),
+        "no_of_groups": len(coordinator_data[GROUPS_LIST]),
+    }

tests/components/tradfri/test_diagnostics.py

@@ -0,0 +1,45 @@
+"""Tests for Tradfri diagnostics."""
+from unittest.mock import MagicMock, Mock
+
+from aiohttp import ClientSession
+
+from homeassistant.core import HomeAssistant
+
+from .common import setup_integration
+from .test_fan import mock_fan
+from .test_light import mock_group
+
+from tests.components.diagnostics import get_diagnostics_for_config_entry
+
+
+async def test_diagnostics(
+    hass: HomeAssistant,
+    hass_client: ClientSession,
+    mock_gateway: Mock,
+    mock_api_factory: MagicMock,
+) -> None:
+    """Test diagnostics for config entry."""
+    mock_gateway.mock_devices.append(
+        # Add a fan
+        mock_fan(
+            test_state={
+                "fan_speed": 10,
+                "air_quality": 42,
+                "filter_lifetime_remaining": 120,
+            }
+        )
+    )
+
+    mock_gateway.mock_groups.append(
+        # Add a group
+        mock_group(test_state={"state": True, "dimmer": 100})
+    )
+
+    init_integration = await setup_integration(hass)
+
+    result = await get_diagnostics_for_config_entry(hass, hass_client, init_integration)
+
+    assert isinstance(result, dict)
+    assert result["gateway_version"] == "1.2.1234"
+    assert len(result["device_data"]) == 1
+    assert result["no_of_groups"] == 1