Share the entity unit lookup and reject unknown temperature units

esphome/components/climate/__init__.py

@@ -49,16 +49,16 @@ from esphome.const import (
     CONF_UNIT_OF_MEASUREMENT,
     CONF_VISUAL,
     CONF_WEB_SERVER,
-    UNIT_CELSIUS,
 )
-from esphome.core import CORE, ID, CoroPriority, coroutine_with_priority
+from esphome.core import CORE, CoroPriority, coroutine_with_priority
 from esphome.core.entity_helpers import (
     entity_duplicate_validator,
+    entity_temperature_unit,
+    entity_temperature_unit_of_id,
     queue_entity_register,
     setup_entity,
 )
 from esphome.cpp_generator import MockObj, MockObjClass
-from esphome.cpp_types import TEMPERATURE_UNITS
 from esphome.types import ConfigType, SafeExpType
 
 IS_PLATFORM_COMPONENT = True
@@ -158,30 +158,17 @@ def visual_temperature_step(value: Any) -> ConfigType:
     return {CONF_TARGET_TEMPERATURE: value, CONF_CURRENT_TEMPERATURE: value}
 
 
-def temperature_unit_of(config: ConfigType) -> str:
-    """The unit a climate reports in: ``unit_of_measurement`` when the platform took the option
-    through ``climate_schema``, else Celsius (anova has an unrelated option of that name)."""
-    unit = config.get(CONF_UNIT_OF_MEASUREMENT)
-    return unit if unit in TEMPERATURE_UNITS else UNIT_CELSIUS
-
-
-def temperature_unit_of_id(climate_id: ID) -> str:
-    """The unit of the climate with this id, for actions that take static temperatures."""
-    path = CORE.config.get_path_for_id(climate_id)[:-1]
-    return temperature_unit_of(CORE.config.get_config_for_path(path))
-
-
 def temperature_in_entity_unit(
     config: ConfigType, value: tuple[float, str | None]
 ) -> str:
     """Render a static action temperature in the unit of the climate the action targets."""
-    unit = temperature_unit_of_id(config[CONF_ID])
+    unit = entity_temperature_unit_of_id(config[CONF_ID])
     return str(cg.safe_exp(cv.convert_temperature(*value, unit)))
 
 
 def _visual_temperatures_in_entity_unit(config: ConfigType) -> ConfigType:
     """Convert the visual temperatures into the entity's unit."""
-    unit = temperature_unit_of(config)
+    unit = entity_temperature_unit(config)
     visual = config[CONF_VISUAL]
     for key in (CONF_MIN_TEMPERATURE, CONF_MAX_TEMPERATURE):
         if isinstance(value := visual.get(key), tuple):

esphome/components/template/climate/__init__.py

@@ -29,6 +29,7 @@ from esphome.const import (
     CONF_TARGET_TEMPERATURE_LOW,
     CONF_UNIT_OF_MEASUREMENT,
 )
+from esphome.core.entity_helpers import entity_temperature_unit
 from esphome.cpp_types import TEMPERATURE_UNITS
 from esphome.types import ConfigType
 
@@ -200,7 +201,7 @@ def _validate_initial_state(config: ConfigType) -> ConfigType:
             f"'{CONF_TARGET_HUMIDITY}' requires '{CONF_SUPPORTS_TARGET_HUMIDITY}' to be enabled",
             path=[CONF_INITIAL_STATE, CONF_TARGET_HUMIDITY],
         )
-    unit = climate.temperature_unit_of(config)
+    unit = entity_temperature_unit(config)
     for key in TEMPERATURE_KEYS:
         if isinstance(value := initial_state.get(key), tuple):
             initial_state[key] = cv.convert_temperature(*value, unit)

esphome/components/template/water_heater/__init__.py

@@ -15,6 +15,7 @@ from esphome.const import (
     CONF_UNIT_OF_MEASUREMENT,
 )
 from esphome.core import ID
+from esphome.core.entity_helpers import entity_temperature_unit_of_id
 from esphome.cpp_generator import MockObj, TemplateArgsType
 from esphome.cpp_types import TEMPERATURE_UNITS
 from esphome.types import ConfigType
@@ -154,7 +155,7 @@ async def water_heater_template_publish_to_code(
     await cg.register_parented(var, config[CONF_ID])
 
     # A static temperature is in the unit of the water heater it is published to
-    unit = water_heater.temperature_unit_of_id(config[CONF_ID])
+    unit = entity_temperature_unit_of_id(config[CONF_ID])
     for key, setter in (
         (CONF_CURRENT_TEMPERATURE, var.set_current_temperature),
         (CONF_TARGET_TEMPERATURE, var.set_target_temperature),

esphome/components/water_heater/__init__.py

@@ -8,16 +8,15 @@ from esphome.const import (
     CONF_MIN_TEMPERATURE,
     CONF_UNIT_OF_MEASUREMENT,
     CONF_VISUAL,
-    UNIT_CELSIUS,
 )
-from esphome.core import CORE, ID, CoroPriority, coroutine_with_priority
+from esphome.core import CORE, CoroPriority, coroutine_with_priority
 from esphome.core.entity_helpers import (
     entity_duplicate_validator,
+    entity_temperature_unit,
     queue_entity_register,
     setup_entity,
 )
 from esphome.cpp_generator import MockObjClass
-from esphome.cpp_types import TEMPERATURE_UNITS
 from esphome.types import ConfigType
 
 CODEOWNERS = ["@dhoeben"]
@@ -45,22 +44,9 @@ WATER_HEATER_MODES = {
 validate_water_heater_mode = cv.enum(WATER_HEATER_MODES, upper=True)
 
 
-def temperature_unit_of(config: ConfigType) -> str:
-    """The unit a water heater reports in: ``unit_of_measurement`` when the platform took the
-    option through ``water_heater_schema``, else Celsius."""
-    unit = config.get(CONF_UNIT_OF_MEASUREMENT)
-    return unit if unit in TEMPERATURE_UNITS else UNIT_CELSIUS
-
-
-def temperature_unit_of_id(water_heater_id: ID) -> str:
-    """The unit of the water heater with this id, for actions that take static temperatures."""
-    path = CORE.config.get_path_for_id(water_heater_id)[:-1]
-    return temperature_unit_of(CORE.config.get_config_for_path(path))
-
-
 def _visual_temperatures_in_entity_unit(config: ConfigType) -> ConfigType:
     """Convert the visual temperatures into the entity's unit."""
-    unit = temperature_unit_of(config)
+    unit = entity_temperature_unit(config)
     visual = config[CONF_VISUAL]
     for key in (CONF_MIN_TEMPERATURE, CONF_MAX_TEMPERATURE):
         if isinstance(value := visual.get(key), tuple):

esphome/config_validation.py

@@ -1472,6 +1472,8 @@ def _temperature_to_celsius(value: float, unit: str, delta: bool) -> float:
         return value * (5 / 9) if delta else (value - 32) * (5 / 9)
     if unit == UNIT_KELVIN:
         return value if delta else value - 273.15
+    if unit != UNIT_CELSIUS:
+        raise ValueError(f"Unknown temperature unit {unit!r}")
     return value
 
 

esphome/core/entity_helpers.py

@@ -16,6 +16,7 @@ from esphome.const import (
     CONF_INTERNAL,
     CONF_NAME,
     CONF_UNIT_OF_MEASUREMENT,
+    UNIT_CELSIUS,
 )
 from esphome.core import CORE, ID, CoroPriority, coroutine_with_priority
 from esphome.core.config import (
@@ -24,7 +25,7 @@ from esphome.core.config import (
     UNIT_OF_MEASUREMENT_MAX_LENGTH,
 )
 from esphome.cpp_generator import MockObj, RawStatement, add, get_variable
-from esphome.cpp_types import App
+from esphome.cpp_types import TEMPERATURE_UNITS, App
 import esphome.final_validate as fv
 from esphome.helpers import (
     cpp_string_escape,
@@ -550,6 +551,19 @@ def inherit_property_from(property_to_inherit, parent_id_property, transform=Non
     return inherit_property
 
 
+def entity_temperature_unit(config: ConfigType) -> str:
+    """The unit a climate or water heater reports in: ``unit_of_measurement`` when the platform took
+    the option through its schema factory, else Celsius (anova has an unrelated option of that name)."""
+    unit = config.get(CONF_UNIT_OF_MEASUREMENT)
+    return unit if unit in TEMPERATURE_UNITS else UNIT_CELSIUS
+
+
+def entity_temperature_unit_of_id(entity_id: ID) -> str:
+    """The unit of the entity with this id, for actions that take static temperatures."""
+    path = CORE.config.get_path_for_id(entity_id)[:-1]
+    return entity_temperature_unit(CORE.config.get_config_for_path(path))
+
+
 def entity_duplicate_validator(platform: str) -> Callable[[ConfigType], ConfigType]:
     """Create a validator function to check for duplicate entity names.
 

tests/component_tests/climate/test_visual_temperatures.py

@@ -4,7 +4,6 @@ import pytest
 
 from esphome.components.climate import (
     _visual_temperatures_in_entity_unit,
-    temperature_unit_of,
     visual_temperature_step,
 )
 from esphome.const import (
@@ -18,6 +17,7 @@ from esphome.const import (
     UNIT_CELSIUS,
     UNIT_FAHRENHEIT,
 )
+from esphome.core.entity_helpers import entity_temperature_unit
 
 
 def test_visual_temperature_step_scalar_applies_to_both() -> None:
@@ -67,9 +67,9 @@ def test_visual_temperatures_follow_unit_of_measurement() -> None:
 
 def test_platform_with_its_own_unit_option_keeps_celsius() -> None:
     # anova validates unit_of_measurement as c|f for the device, not for the entity
-    assert temperature_unit_of({CONF_UNIT_OF_MEASUREMENT: "f"}) == UNIT_CELSIUS
+    assert entity_temperature_unit({CONF_UNIT_OF_MEASUREMENT: "f"}) == UNIT_CELSIUS
     assert (
-        temperature_unit_of({CONF_UNIT_OF_MEASUREMENT: UNIT_FAHRENHEIT})
+        entity_temperature_unit({CONF_UNIT_OF_MEASUREMENT: UNIT_FAHRENHEIT})
         == UNIT_FAHRENHEIT
     )