Ignore loading system entity category (#71361)

homeassistant/helpers/entity_registry.py

@@ -711,6 +711,10 @@ class EntityRegistry:
                 if not valid_entity_id(entity["entity_id"]):
                     continue
 
+                # We removed this in 2022.5. Remove this check in 2023.1.
+                if entity["entity_category"] == "system":
+                    entity["entity_category"] = None
+
                 entities[entity["entity_id"]] = RegistryEntry(
                     area_id=entity["area_id"],
                     capabilities=entity["capabilities"],

tests/helpers/test_entity_registry.py

@@ -297,6 +297,12 @@ async def test_loading_extra_values(hass, hass_storage):
                     "unique_id": "invalid-hass",
                     "disabled_by": er.RegistryEntryDisabler.HASS,
                 },
+                {
+                    "entity_id": "test.system_entity",
+                    "platform": "super_platform",
+                    "unique_id": "system-entity",
+                    "entity_category": "system",
+                },
             ]
         },
     }
@@ -304,7 +310,7 @@ async def test_loading_extra_values(hass, hass_storage):
     await er.async_load(hass)
     registry = er.async_get(hass)
 
-    assert len(registry.entities) == 4
+    assert len(registry.entities) == 5
 
     entry_with_name = registry.async_get_or_create(
         "test", "super_platform", "with-name"
@@ -327,6 +333,11 @@ async def test_loading_extra_values(hass, hass_storage):
     assert entry_disabled_user.disabled
     assert entry_disabled_user.disabled_by is er.RegistryEntryDisabler.USER
 
+    entry_system_category = registry.async_get_or_create(
+        "test", "system_entity", "system-entity"
+    )
+    assert entry_system_category.entity_category is None
+
 
 def test_async_get_entity_id(registry):
     """Test that entity_id is returned."""