[water_heater] Add On/Off and Away mode support to template platform (#13839)

Co-authored-by: J. Nick Koston <nick@koston.org>
Co-authored-by: J. Nick Koston <nick@home-assistant.io>

tests/components/template/common-base.yaml

@@ -13,6 +13,8 @@ esphome:
         id: template_water_heater
         target_temperature: 50.0
         mode: ECO
+        away: false
+        is_on: true
 
     # Templated
     - water_heater.template.publish:
@@ -20,6 +22,8 @@ esphome:
         current_temperature: !lambda "return 45.0;"
         target_temperature: !lambda "return 55.0;"
         mode: !lambda "return water_heater::WATER_HEATER_MODE_GAS;"
+        away: !lambda "return true;"
+        is_on: !lambda "return false;"
 
     # Test C++ API: set_template() with stateless lambda (no captures)
     # NOTE: set_template() is not intended to be a public API, but we test it to ensure it doesn't break.
@@ -414,6 +418,8 @@ water_heater:
     current_temperature: !lambda "return 42.0f;"
     target_temperature: !lambda "return 60.0f;"
     mode: !lambda "return water_heater::WATER_HEATER_MODE_ECO;"
+    away: !lambda "return false;"
+    is_on: !lambda "return true;"
     supported_modes:
       - "OFF"
       - ECO

tests/integration/fixtures/water_heater_template.yaml

@@ -4,6 +4,14 @@ host:
 api:
 logger:
 
+globals:
+  - id: global_away
+    type: bool
+    initial_value: "false"
+  - id: global_is_on
+    type: bool
+    initial_value: "true"
+
 water_heater:
   - platform: template
     id: test_boiler
@@ -11,6 +19,8 @@ water_heater:
     optimistic: true
     current_temperature: !lambda "return 45.0f;"
     target_temperature: !lambda "return 60.0f;"
+    away: !lambda "return id(global_away);"
+    is_on: !lambda "return id(global_is_on);"
     # Note: No mode lambda - we want optimistic mode changes to stick
     # A mode lambda would override mode changes in loop()
     supported_modes:
@@ -22,3 +32,8 @@ water_heater:
       min_temperature: 30.0
       max_temperature: 85.0
       target_temperature_step: 0.5
+    set_action:
+      - lambda: |-
+          // Sync optimistic state back to globals so lambdas reflect the change
+          id(global_away) = id(test_boiler).is_away();
+          id(global_is_on) = id(test_boiler).is_on();

tests/integration/test_water_heater_template.py

@@ -5,7 +5,13 @@ from __future__ import annotations
 import asyncio
 
 import aioesphomeapi
-from aioesphomeapi import WaterHeaterInfo, WaterHeaterMode, WaterHeaterState
+from aioesphomeapi import (
+    WaterHeaterFeature,
+    WaterHeaterInfo,
+    WaterHeaterMode,
+    WaterHeaterState,
+    WaterHeaterStateFlag,
+)
 import pytest
 
 from .state_utils import InitialStateHelper
@@ -22,18 +28,25 @@ async def test_water_heater_template(
     loop = asyncio.get_running_loop()
     async with run_compiled(yaml_config), api_client_connected() as client:
         states: dict[int, aioesphomeapi.EntityState] = {}
-        gas_mode_future: asyncio.Future[WaterHeaterState] = loop.create_future()
-        eco_mode_future: asyncio.Future[WaterHeaterState] = loop.create_future()
+        state_future: asyncio.Future[WaterHeaterState] | None = None
 
         def on_state(state: aioesphomeapi.EntityState) -> None:
             states[state.key] = state
-            if isinstance(state, WaterHeaterState):
-                # Wait for GAS mode
-                if state.mode == WaterHeaterMode.GAS and not gas_mode_future.done():
-                    gas_mode_future.set_result(state)
-                # Wait for ECO mode (we start at OFF, so test transitioning to ECO)
-                elif state.mode == WaterHeaterMode.ECO and not eco_mode_future.done():
-                    eco_mode_future.set_result(state)
+            if (
+                isinstance(state, WaterHeaterState)
+                and state_future is not None
+                and not state_future.done()
+            ):
+                state_future.set_result(state)
+
+        async def wait_for_state(timeout: float = 5.0) -> WaterHeaterState:
+            """Wait for next water heater state change."""
+            nonlocal state_future
+            state_future = loop.create_future()
+            try:
+                return await asyncio.wait_for(state_future, timeout)
+            finally:
+                state_future = None
 
         # Get entities and set up state synchronization
         entities, services = await client.list_entities_services()
@@ -89,24 +102,52 @@ async def test_water_heater_template(
             f"Expected target temp 60.0, got {initial_state.target_temperature}"
         )
 
+        # Verify supported features: away mode and on/off (fixture has away + is_on lambdas)
+        assert (
+            test_water_heater.supported_features & WaterHeaterFeature.SUPPORTS_AWAY_MODE
+        ) != 0, "Expected SUPPORTS_AWAY_MODE in supported_features"
+        assert (
+            test_water_heater.supported_features & WaterHeaterFeature.SUPPORTS_ON_OFF
+        ) != 0, "Expected SUPPORTS_ON_OFF in supported_features"
+
+        # Verify initial state: on (is_on lambda returns true), not away (away lambda returns false)
+        assert (initial_state.state & WaterHeaterStateFlag.ON) != 0, (
+            "Expected initial state to include ON flag"
+        )
+        assert (initial_state.state & WaterHeaterStateFlag.AWAY) == 0, (
+            "Expected initial state to not include AWAY flag"
+        )
+
+        # Test turning on away mode
+        client.water_heater_command(test_water_heater.key, away=True)
+        away_on_state = await wait_for_state()
+        assert (away_on_state.state & WaterHeaterStateFlag.AWAY) != 0
+        # ON flag should still be set (is_on lambda returns true)
+        assert (away_on_state.state & WaterHeaterStateFlag.ON) != 0
+
+        # Test turning off away mode
+        client.water_heater_command(test_water_heater.key, away=False)
+        away_off_state = await wait_for_state()
+        assert (away_off_state.state & WaterHeaterStateFlag.AWAY) == 0
+        assert (away_off_state.state & WaterHeaterStateFlag.ON) != 0
+
+        # Test turning off (on=False)
+        client.water_heater_command(test_water_heater.key, on=False)
+        off_state = await wait_for_state()
+        assert (off_state.state & WaterHeaterStateFlag.ON) == 0
+        assert (off_state.state & WaterHeaterStateFlag.AWAY) == 0
+
+        # Test turning back on (on=True)
+        client.water_heater_command(test_water_heater.key, on=True)
+        on_state = await wait_for_state()
+        assert (on_state.state & WaterHeaterStateFlag.ON) != 0
+
         # Test changing to GAS mode
         client.water_heater_command(test_water_heater.key, mode=WaterHeaterMode.GAS)
-
-        try:
-            gas_state = await asyncio.wait_for(gas_mode_future, timeout=5.0)
-        except TimeoutError:
-            pytest.fail("GAS mode change not received within 5 seconds")
-
-        assert isinstance(gas_state, WaterHeaterState)
+        gas_state = await wait_for_state()
         assert gas_state.mode == WaterHeaterMode.GAS
 
         # Test changing to ECO mode (from GAS)
         client.water_heater_command(test_water_heater.key, mode=WaterHeaterMode.ECO)
-
-        try:
-            eco_state = await asyncio.wait_for(eco_mode_future, timeout=5.0)
-        except TimeoutError:
-            pytest.fail("ECO mode change not received within 5 seconds")
-
-        assert isinstance(eco_state, WaterHeaterState)
+        eco_state = await wait_for_state()
         assert eco_state.mode == WaterHeaterMode.ECO