[climate] Fold ControlAction fields into a single stateless lambda (#16044)

tests/integration/fixtures/climate_control_action.yaml

@@ -0,0 +1,92 @@
+esphome:
+  name: climate-control-action-test
+host:
+api:
+logger:
+  level: DEBUG
+
+globals:
+  - id: test_target_temp
+    type: float
+    initial_value: "21.5"
+
+sensor:
+  - platform: template
+    id: temp_sensor
+    name: "Temp"
+    lambda: 'return 20.0;'
+    update_interval: 60s
+
+climate:
+  - platform: thermostat
+    id: test_climate
+    name: "Test Climate"
+    sensor: temp_sensor
+    min_idle_time: 30s
+    min_heating_off_time: 300s
+    min_heating_run_time: 300s
+    min_cooling_off_time: 300s
+    min_cooling_run_time: 300s
+    heat_action:
+      - logger.log: heating
+    idle_action:
+      - logger.log: idle
+    cool_action:
+      - logger.log: cooling
+    heat_cool_mode:
+      - logger.log: heat_cool
+    preset:
+      - name: Default
+        default_target_temperature_low: 18 °C
+        default_target_temperature_high: 22 °C
+    visual:
+      min_temperature: 10 °C
+      max_temperature: 30 °C
+
+button:
+  # mode only
+  - platform: template
+    id: btn_mode
+    name: "Set Mode Heat"
+    on_press:
+      - climate.control:
+          id: test_climate
+          mode: HEAT
+
+  # mode + target_temperature_low + target_temperature_high
+  - platform: template
+    id: btn_mode_temps
+    name: "Set Mode Temps"
+    on_press:
+      - climate.control:
+          id: test_climate
+          mode: HEAT_COOL
+          target_temperature_low: 19.0 °C
+          target_temperature_high: 23.0 °C
+
+  # target_temperature_low only
+  - platform: template
+    id: btn_low_only
+    name: "Set Low Only"
+    on_press:
+      - climate.control:
+          id: test_climate
+          target_temperature_low: 17.5 °C
+
+  # Lambda path: target_temperature_high computed at runtime
+  - platform: template
+    id: btn_lambda_high
+    name: "Lambda High"
+    on_press:
+      - climate.control:
+          id: test_climate
+          target_temperature_high: !lambda "return id(test_target_temp);"
+
+  # mode only — turn off via mode
+  - platform: template
+    id: btn_off
+    name: "Set Off"
+    on_press:
+      - climate.control:
+          id: test_climate
+          mode: "OFF"

tests/integration/test_climate_control_action.py

@@ -0,0 +1,84 @@
+"""Integration test for climate ControlAction.
+
+Tests that climate.control automation actions work correctly with the
+single stateless apply lambda/function pointer implementation. Exercises
+multiple field combinations and the lambda path.
+"""
+
+from __future__ import annotations
+
+import asyncio
+
+from aioesphomeapi import (
+    ButtonInfo,
+    ClimateInfo,
+    ClimateMode,
+    ClimateState,
+    EntityState,
+)
+import pytest
+
+from .state_utils import InitialStateHelper, require_entity
+from .types import APIClientConnectedFactory, RunCompiledFunction
+
+
+@pytest.mark.asyncio
+async def test_climate_control_action(
+    yaml_config: str,
+    run_compiled: RunCompiledFunction,
+    api_client_connected: APIClientConnectedFactory,
+) -> None:
+    """Test climate ControlAction with constants and lambdas."""
+    loop = asyncio.get_running_loop()
+    async with run_compiled(yaml_config), api_client_connected() as client:
+        climate_state_future: asyncio.Future[ClimateState] | None = None
+
+        def on_state(state: EntityState) -> None:
+            if (
+                isinstance(state, ClimateState)
+                and climate_state_future is not None
+                and not climate_state_future.done()
+            ):
+                climate_state_future.set_result(state)
+
+        async def wait_for_climate_state(timeout: float = 5.0) -> ClimateState:
+            nonlocal climate_state_future
+            climate_state_future = loop.create_future()
+            try:
+                return await asyncio.wait_for(climate_state_future, timeout)
+            finally:
+                climate_state_future = None
+
+        entities, _ = await client.list_entities_services()
+        initial_state_helper = InitialStateHelper(entities)
+        client.subscribe_states(initial_state_helper.on_state_wrapper(on_state))
+        await initial_state_helper.wait_for_initial_states()
+
+        require_entity(entities, "test_climate", ClimateInfo)
+
+        async def press_and_wait(name: str) -> ClimateState:
+            btn = require_entity(entities, name.lower().replace(" ", "_"), ButtonInfo)
+            client.button_command(btn.key)
+            return await wait_for_climate_state()
+
+        # mode only — set HEAT
+        state = await press_and_wait("Set Mode Heat")
+        assert state.mode == ClimateMode.HEAT
+
+        # mode + target_temperature_low + target_temperature_high
+        state = await press_and_wait("Set Mode Temps")
+        assert state.mode == ClimateMode.HEAT_COOL
+        assert state.target_temperature_low == pytest.approx(19.0, abs=0.5)
+        assert state.target_temperature_high == pytest.approx(23.0, abs=0.5)
+
+        # target_temperature_low only
+        state = await press_and_wait("Set Low Only")
+        assert state.target_temperature_low == pytest.approx(17.5, abs=0.5)
+
+        # lambda path: target_temperature_high computed at runtime
+        state = await press_and_wait("Lambda High")
+        assert state.target_temperature_high == pytest.approx(21.5, abs=0.5)
+
+        # mode only — turn off via mode
+        state = await press_and_wait("Set Off")
+        assert state.mode == ClimateMode.OFF