Generic thermostat temp step (#70303)

* Add target_temp_step to generic_thermostat

* Add target_temp_step to generic_thermostat : fix default + add tests

* Add target_temp_step to generic_thermostat : fix test by using new 'units_imperial' fixture

homeassistant/components/generic_thermostat/climate.py

@@ -75,6 +75,7 @@ CONF_HOT_TOLERANCE = "hot_tolerance"
 CONF_KEEP_ALIVE = "keep_alive"
 CONF_INITIAL_HVAC_MODE = "initial_hvac_mode"
 CONF_PRECISION = "precision"
+CONF_TEMP_STEP = "target_temp_step"
 
 CONF_PRESETS = {
     p: f"{p}_temp"
@@ -106,6 +107,9 @@ PLATFORM_SCHEMA = PLATFORM_SCHEMA.extend(
         vol.Optional(CONF_PRECISION): vol.In(
             [PRECISION_TENTHS, PRECISION_HALVES, PRECISION_WHOLE]
         ),
+        vol.Optional(CONF_TEMP_STEP): vol.In(
+            [PRECISION_TENTHS, PRECISION_HALVES, PRECISION_WHOLE]
+        ),
         vol.Optional(CONF_UNIQUE_ID): cv.string,
     }
 ).extend({vol.Optional(v): vol.Coerce(float) for (k, v) in CONF_PRESETS.items()})
@@ -137,6 +141,7 @@ async def async_setup_platform(
         key: config[value] for key, value in CONF_PRESETS.items() if value in config
     }
     precision = config.get(CONF_PRECISION)
+    target_temperature_step = config.get(CONF_TEMP_STEP)
     unit = hass.config.units.temperature_unit
     unique_id = config.get(CONF_UNIQUE_ID)
 
@@ -157,6 +162,7 @@ async def async_setup_platform(
                 initial_hvac_mode,
                 presets,
                 precision,
+                target_temperature_step,
                 unit,
                 unique_id,
             )
@@ -183,6 +189,7 @@ class GenericThermostat(ClimateEntity, RestoreEntity):
         initial_hvac_mode,
         presets,
         precision,
+        target_temperature_step,
         unit,
         unique_id,
     ):
@@ -198,6 +205,7 @@ class GenericThermostat(ClimateEntity, RestoreEntity):
         self._hvac_mode = initial_hvac_mode
         self._saved_target_temp = target_temp or next(iter(presets.values()), None)
         self._temp_precision = precision
+        self._temp_target_temperature_step = target_temperature_step
         if self.ac_mode:
             self._hvac_list = [HVAC_MODE_COOL, HVAC_MODE_OFF]
         else:
@@ -325,8 +333,9 @@ class GenericThermostat(ClimateEntity, RestoreEntity):
     @property
     def target_temperature_step(self):
         """Return the supported step of target temperature."""
-        # Since this integration does not yet have a step size parameter
-        # we have to re-use the precision as the step size for now.
+        if self._temp_target_temperature_step is not None:
+            return self._temp_target_temperature_step
+        # if a target_temperature_step is not defined, fallback to equal the precision
         return self.precision
 
     @property

tests/components/generic_thermostat/test_climate.py

@@ -33,7 +33,6 @@ from homeassistant.const import (
     STATE_UNAVAILABLE,
     STATE_UNKNOWN,
     TEMP_CELSIUS,
-    TEMP_FAHRENHEIT,
 )
 import homeassistant.core as ha
 from homeassistant.core import DOMAIN as HASS_DOMAIN, CoreState, State, callback
@@ -62,6 +61,7 @@ MAX_TEMP = 65.0
 TARGET_TEMP = 42.0
 COLD_TOLERANCE = 0.5
 HOT_TOLERANCE = 0.5
+TARGET_TEMP_STEP = 0.5
 
 
 async def test_setup_missing_conf(hass):
@@ -276,6 +276,7 @@ async def test_default_setup_params(hass, setup_comp_2):
     assert state.attributes.get("min_temp") == 7
     assert state.attributes.get("max_temp") == 35
     assert state.attributes.get("temperature") == 7
+    assert state.attributes.get("target_temp_step") == 0.1
 
 
 async def test_get_hvac_modes(hass, setup_comp_2):
@@ -1179,7 +1180,6 @@ async def test_temp_change_heater_trigger_off_long_enough_2(hass, setup_comp_8):
 @pytest.fixture
 async def setup_comp_9(hass):
     """Initialize components."""
-    hass.config.temperature_unit = TEMP_FAHRENHEIT
     assert await async_setup_component(
         hass,
         DOMAIN,
@@ -1201,11 +1201,13 @@ async def setup_comp_9(hass):
     await hass.async_block_till_done()
 
 
-async def test_precision(hass, setup_comp_9):
+async def test_precision(hass, units_imperial, setup_comp_9):
     """Test that setting precision to tenths works as intended."""
     await common.async_set_temperature(hass, 23.27)
     state = hass.states.get(ENTITY)
     assert state.attributes.get("temperature") == 23.3
+    # check that target_temp_step defaults to precision
+    assert state.attributes.get("target_temp_step") == 0.1
 
 
 async def test_custom_setup_params(hass):
@@ -1222,6 +1224,7 @@ async def test_custom_setup_params(hass):
                 "min_temp": MIN_TEMP,
                 "max_temp": MAX_TEMP,
                 "target_temp": TARGET_TEMP,
+                "target_temp_step": 0.5,
             }
         },
     )
@@ -1231,6 +1234,7 @@ async def test_custom_setup_params(hass):
     assert state.attributes.get("min_temp") == MIN_TEMP
     assert state.attributes.get("max_temp") == MAX_TEMP
     assert state.attributes.get("temperature") == TARGET_TEMP
+    assert state.attributes.get("target_temp_step") == TARGET_TEMP_STEP
 
 
 @pytest.mark.parametrize("hvac_mode", [HVAC_MODE_OFF, HVAC_MODE_HEAT, HVAC_MODE_COOL])