Add diagnostics support to CPU Speed (#64745)

* Add diagnostics support to CPU Speed

* Fix copy pasta error

tests/components/cpuspeed/test_diagnostics.py

@@ -0,0 +1,36 @@
+"""Tests for the diagnostics data provided by the CPU Speed integration."""
+from unittest.mock import patch
+
+from aiohttp import ClientSession
+
+from homeassistant.core import HomeAssistant
+
+from tests.common import MockConfigEntry
+from tests.components.diagnostics import get_diagnostics_for_config_entry
+
+
+async def test_diagnostics(
+    hass: HomeAssistant,
+    hass_client: ClientSession,
+    init_integration: MockConfigEntry,
+):
+    """Test diagnostics."""
+    info = {
+        "hz_actual": (3200000001, 0),
+        "arch_string_raw": "aargh",
+        "brand_raw": "Intel Ryzen 7",
+        "hz_advertised": (3600000001, 0),
+    }
+
+    with patch(
+        "homeassistant.components.cpuspeed.diagnostics.cpuinfo.get_cpu_info",
+        return_value=info,
+    ):
+        assert await get_diagnostics_for_config_entry(
+            hass, hass_client, init_integration
+        ) == {
+            "hz_actual": [3200000001, 0],
+            "arch_string_raw": "aargh",
+            "brand_raw": "Intel Ryzen 7",
+            "hz_advertised": [3600000001, 0],
+        }