Use cached_property in entity_registry (#100302)

homeassistant/helpers/entity_registry.py

@@ -20,6 +20,7 @@ from typing import TYPE_CHECKING, Any, Literal, NotRequired, TypedDict, TypeVar,
 import attr
 import voluptuous as vol
 
+from homeassistant.backports.functools import cached_property
 from homeassistant.const import (
     ATTR_DEVICE_CLASS,
     ATTR_FRIENDLY_NAME,
@@ -148,7 +149,7 @@ def _protect_entity_options(
     return ReadOnlyDict({key: ReadOnlyDict(val) for key, val in data.items()})
 
 
-@attr.s(slots=True, frozen=True)
+@attr.s(frozen=True)
 class RegistryEntry:
     """Entity Registry Entry."""
 
@@ -183,13 +184,6 @@ class RegistryEntry:
     translation_key: str | None = attr.ib(default=None)
     unit_of_measurement: str | None = attr.ib(default=None)
 
-    _partial_repr: str | None | UndefinedType = attr.ib(
-        cmp=False, default=UNDEFINED, init=False, repr=False
-    )
-    _display_repr: str | None | UndefinedType = attr.ib(
-        cmp=False, default=UNDEFINED, init=False, repr=False
-    )
-
     @domain.default
     def _domain_default(self) -> str:
         """Compute domain value."""
@@ -231,21 +225,17 @@ class RegistryEntry:
                 display_dict["dp"] = precision
         return display_dict
 
-    @property
+    @cached_property
     def display_json_repr(self) -> str | None:
         """Return a cached partial JSON representation of the entry.
 
         This version only includes what's needed for display.
         """
-        if self._display_repr is not UNDEFINED:
-            return self._display_repr
-
         try:
             dict_repr = self._as_display_dict
             json_repr: str | None = JSON_DUMP(dict_repr) if dict_repr else None
-            object.__setattr__(self, "_display_repr", json_repr)
+            return json_repr
         except (ValueError, TypeError):
-            object.__setattr__(self, "_display_repr", None)
             _LOGGER.error(
                 "Unable to serialize entry %s to JSON. Bad data found at %s",
                 self.entity_id,
@@ -253,8 +243,8 @@ class RegistryEntry:
                     find_paths_unserializable_data(dict_repr, dump=JSON_DUMP)
                 ),
             )
-        # Mypy doesn't understand the __setattr__ business
-        return self._display_repr  # type: ignore[return-value]
+
+        return None
 
     @property
     def as_partial_dict(self) -> dict[str, Any]:
@@ -278,17 +268,13 @@ class RegistryEntry:
             "unique_id": self.unique_id,
         }
 
-    @property
+    @cached_property
     def partial_json_repr(self) -> str | None:
         """Return a cached partial JSON representation of the entry."""
-        if self._partial_repr is not UNDEFINED:
-            return self._partial_repr
-
         try:
             dict_repr = self.as_partial_dict
-            object.__setattr__(self, "_partial_repr", JSON_DUMP(dict_repr))
+            return JSON_DUMP(dict_repr)
         except (ValueError, TypeError):
-            object.__setattr__(self, "_partial_repr", None)
             _LOGGER.error(
                 "Unable to serialize entry %s to JSON. Bad data found at %s",
                 self.entity_id,
@@ -296,8 +282,7 @@ class RegistryEntry:
                     find_paths_unserializable_data(dict_repr, dump=JSON_DUMP)
                 ),
             )
-        # Mypy doesn't understand the __setattr__ business
-        return self._partial_repr  # type: ignore[return-value]
+        return None
 
     @callback
     def write_unavailable_state(self, hass: HomeAssistant) -> None:

tests/syrupy.py

@@ -166,7 +166,7 @@ class HomeAssistantSnapshotSerializer(AmberDataSerializer):
         cls, data: er.RegistryEntry
     ) -> SerializableData:
         """Prepare a Home Assistant entity registry entry for serialization."""
-        serialized = EntityRegistryEntrySnapshot(
+        return EntityRegistryEntrySnapshot(
             attrs.asdict(data)
             | {
                 "config_entry_id": ANY,
@@ -175,9 +175,6 @@ class HomeAssistantSnapshotSerializer(AmberDataSerializer):
                 "options": {k: dict(v) for k, v in data.options.items()},
             }
         )
-        serialized.pop("_partial_repr")
-        serialized.pop("_display_repr")
-        return serialized
 
     @classmethod
     def _serializable_flow_result(cls, data: FlowResult) -> SerializableData: