Use TimerEntityStateAttribute enum in timer (#175971)

Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

homeassistant/components/timer/__init__.py

@@ -292,20 +292,26 @@ class Timer(collection.CollectionEntity, RestoreEntity):
 
         # Begin restoring state
         self._state = state.state
-        self._last_transition = state.attributes.get(ATTR_LAST_TRANSITION)
+        self._last_transition = state.attributes.get(
+            TimerEntityStateAttribute.LAST_TRANSITION
+        )
 
         # Nothing more to do if the timer is idle
         if self._state == STATUS_IDLE:
             return
 
-        self._running_duration = cv.time_period(state.attributes[ATTR_DURATION])
+        self._running_duration = cv.time_period(
+            state.attributes[TimerEntityStateAttribute.DURATION]
+        )
         # If the timer was paused, we restore the remaining time
         if self._state == STATUS_PAUSED:
-            self._remaining = cv.time_period(state.attributes[ATTR_REMAINING])
+            self._remaining = cv.time_period(
+                state.attributes[TimerEntityStateAttribute.REMAINING]
+            )
             return
         # If we get here, the timer must have been active so we need to decide what
         # to do based on end time and the current time
-        end = cv.datetime(state.attributes[ATTR_FINISHES_AT])
+        end = cv.datetime(state.attributes[TimerEntityStateAttribute.FINISHES_AT])
         # If there is time remaining in the timer, restore the remaining time then
         # start the timer
         if (remaining := end - dt_util.utcnow().replace(microsecond=0)) > timedelta(0):

homeassistant/components/timer/reproduce_state.py

@@ -17,6 +17,7 @@ from . import (
     STATUS_ACTIVE,
     STATUS_IDLE,
     STATUS_PAUSED,
+    TimerEntityStateAttribute,
 )
 
 _LOGGER = logging.getLogger(__name__)
@@ -45,15 +46,17 @@ async def _async_reproduce_state(
     # Return if we are already at the right state.
     if cur_state.state == state.state and cur_state.attributes.get(
         ATTR_DURATION
-    ) == state.attributes.get(ATTR_DURATION):
+    ) == state.attributes.get(TimerEntityStateAttribute.DURATION):
         return
 
     service_data = {ATTR_ENTITY_ID: state.entity_id}
 
     if state.state == STATUS_ACTIVE:
         service = SERVICE_START
-        if ATTR_DURATION in state.attributes:
-            service_data[ATTR_DURATION] = state.attributes[ATTR_DURATION]
+        if TimerEntityStateAttribute.DURATION in state.attributes:
+            service_data[ATTR_DURATION] = state.attributes[
+                TimerEntityStateAttribute.DURATION
+            ]
     elif state.state == STATUS_PAUSED:
         service = SERVICE_PAUSE
     elif state.state == STATUS_IDLE:

homeassistant/components/timer/trigger.py

@@ -26,7 +26,8 @@ from homeassistant.helpers.trigger import (
 from homeassistant.helpers.typing import ConfigType
 from homeassistant.util import dt as dt_util
 
-from . import ATTR_FINISHES_AT, ATTR_LAST_TRANSITION, DOMAIN, STATUS_ACTIVE
+from . import DOMAIN, STATUS_ACTIVE
+from .const import TimerEntityStateAttribute
 
 CONF_REMAINING = "remaining"
 
@@ -86,7 +87,9 @@ class TimeRemainingTrigger(Trigger):
             if to_state.state != STATUS_ACTIVE:
                 return
 
-            finishes_at_str = to_state.attributes.get(ATTR_FINISHES_AT)
+            finishes_at_str = to_state.attributes.get(
+                TimerEntityStateAttribute.FINISHES_AT
+            )
             if finishes_at_str is None:
                 return
 
@@ -166,19 +169,24 @@ class TimeRemainingTrigger(Trigger):
 
 TRIGGERS: dict[str, type[Trigger]] = {
     "cancelled": make_entity_target_state_trigger(
-        {DOMAIN: DomainSpec(value_source=ATTR_LAST_TRANSITION)}, "cancelled"
+        {DOMAIN: DomainSpec(value_source=TimerEntityStateAttribute.LAST_TRANSITION)},
+        "cancelled",
     ),
     "finished": make_entity_target_state_trigger(
-        {DOMAIN: DomainSpec(value_source=ATTR_LAST_TRANSITION)}, "finished"
+        {DOMAIN: DomainSpec(value_source=TimerEntityStateAttribute.LAST_TRANSITION)},
+        "finished",
     ),
     "paused": make_entity_target_state_trigger(
-        {DOMAIN: DomainSpec(value_source=ATTR_LAST_TRANSITION)}, "paused"
+        {DOMAIN: DomainSpec(value_source=TimerEntityStateAttribute.LAST_TRANSITION)},
+        "paused",
     ),
     "restarted": make_entity_target_state_trigger(
-        {DOMAIN: DomainSpec(value_source=ATTR_LAST_TRANSITION)}, "restarted"
+        {DOMAIN: DomainSpec(value_source=TimerEntityStateAttribute.LAST_TRANSITION)},
+        "restarted",
     ),
     "started": make_entity_target_state_trigger(
-        {DOMAIN: DomainSpec(value_source=ATTR_LAST_TRANSITION)}, "started"
+        {DOMAIN: DomainSpec(value_source=TimerEntityStateAttribute.LAST_TRANSITION)},
+        "started",
     ),
     "remaining_time_reached": TimeRemainingTrigger,
 }