Normalize temperature statistics to °C (#52297)

* Normalize temperature statistics to °C

* Fix tests

* Support temperature conversion to and from K, improve tests

* Fix test

* Add tests, pylint

homeassistant/components/sensor/recorder.py

@@ -4,6 +4,7 @@ from __future__ import annotations
 import datetime
 import itertools
 import logging
+from typing import Callable
 
 from homeassistant.components.recorder import history, statistics
 from homeassistant.components.sensor import (
@@ -31,10 +32,13 @@ from homeassistant.const import (
     PRESSURE_PA,
     PRESSURE_PSI,
     TEMP_CELSIUS,
+    TEMP_FAHRENHEIT,
+    TEMP_KELVIN,
 )
 from homeassistant.core import HomeAssistant, State
 import homeassistant.util.dt as dt_util
 import homeassistant.util.pressure as pressure_util
+import homeassistant.util.temperature as temperature_util
 
 from . import DOMAIN
 
@@ -57,7 +61,7 @@ DEVICE_CLASS_UNITS = {
     DEVICE_CLASS_TEMPERATURE: TEMP_CELSIUS,
 }
 
-UNIT_CONVERSIONS = {
+UNIT_CONVERSIONS: dict[str, dict[str, Callable]] = {
     DEVICE_CLASS_ENERGY: {
         ENERGY_KILO_WATT_HOUR: lambda x: x,
         ENERGY_WATT_HOUR: lambda x: x / 1000,
@@ -74,6 +78,11 @@ UNIT_CONVERSIONS = {
         PRESSURE_PA: lambda x: x / pressure_util.UNIT_CONVERSION[PRESSURE_PA],
         PRESSURE_PSI: lambda x: x / pressure_util.UNIT_CONVERSION[PRESSURE_PSI],
     },
+    DEVICE_CLASS_TEMPERATURE: {
+        TEMP_CELSIUS: lambda x: x,
+        TEMP_FAHRENHEIT: temperature_util.fahrenheit_to_celsius,
+        TEMP_KELVIN: temperature_util.kelvin_to_celsius,
+    },
 }
 
 WARN_UNSUPPORTED_UNIT = set()
@@ -169,7 +178,7 @@ def _normalize_states(
                 _LOGGER.warning("%s has unknown unit %s", entity_id, unit)
             continue
 
-        fstates.append((UNIT_CONVERSIONS[device_class][unit](fstate), state))  # type: ignore
+        fstates.append((UNIT_CONVERSIONS[device_class][unit](fstate), state))
 
     return DEVICE_CLASS_UNITS[device_class], fstates
 
@@ -229,6 +238,7 @@ def compile_statistics(
                 _sum = last_stats[entity_id][0]["sum"]
 
             for fstate, state in fstates:
+
                 if "last_reset" not in state.attributes:
                     continue
                 if (last_reset := state.attributes["last_reset"]) != old_last_reset:

homeassistant/util/temperature.py

@@ -2,6 +2,7 @@
 from homeassistant.const import (
     TEMP_CELSIUS,
     TEMP_FAHRENHEIT,
+    TEMP_KELVIN,
     TEMPERATURE,
     UNIT_NOT_RECOGNIZED_TEMPLATE,
 )
@@ -14,6 +15,13 @@ def fahrenheit_to_celsius(fahrenheit: float, interval: bool = False) -> float:
     return (fahrenheit - 32.0) / 1.8
 
 
+def kelvin_to_celsius(kelvin: float, interval: bool = False) -> float:
+    """Convert a temperature in Kelvin to Celsius."""
+    if interval:
+        return kelvin
+    return kelvin - 273.15
+
+
 def celsius_to_fahrenheit(celsius: float, interval: bool = False) -> float:
     """Convert a temperature in Celsius to Fahrenheit."""
     if interval:
@@ -21,17 +29,39 @@ def celsius_to_fahrenheit(celsius: float, interval: bool = False) -> float:
     return celsius * 1.8 + 32.0
 
 
+def celsius_to_kelvin(celsius: float, interval: bool = False) -> float:
+    """Convert a temperature in Celsius to Fahrenheit."""
+    if interval:
+        return celsius
+    return celsius + 273.15
+
+
 def convert(
     temperature: float, from_unit: str, to_unit: str, interval: bool = False
 ) -> float:
     """Convert a temperature from one unit to another."""
-    if from_unit not in (TEMP_CELSIUS, TEMP_FAHRENHEIT):
+    if from_unit not in (TEMP_CELSIUS, TEMP_FAHRENHEIT, TEMP_KELVIN):
         raise ValueError(UNIT_NOT_RECOGNIZED_TEMPLATE.format(from_unit, TEMPERATURE))
-    if to_unit not in (TEMP_CELSIUS, TEMP_FAHRENHEIT):
+    if to_unit not in (TEMP_CELSIUS, TEMP_FAHRENHEIT, TEMP_KELVIN):
         raise ValueError(UNIT_NOT_RECOGNIZED_TEMPLATE.format(to_unit, TEMPERATURE))
 
     if from_unit == to_unit:
         return temperature
+
     if from_unit == TEMP_CELSIUS:
+        if to_unit == TEMP_FAHRENHEIT:
             return celsius_to_fahrenheit(temperature, interval)
+        # kelvin
+        return celsius_to_kelvin(temperature, interval)
+
+    if from_unit == TEMP_FAHRENHEIT:
+        if to_unit == TEMP_CELSIUS:
             return fahrenheit_to_celsius(temperature, interval)
+        # kelvin
+        return celsius_to_kelvin(fahrenheit_to_celsius(temperature, interval), interval)
+
+    # from_unit == kelvin
+    if to_unit == TEMP_CELSIUS:
+        return kelvin_to_celsius(temperature, interval)
+    # fahrenheit
+    return celsius_to_fahrenheit(kelvin_to_celsius(temperature, interval), interval)

tests/components/history/test_init.py

@@ -840,7 +840,11 @@ async def test_statistics_during_period(hass, hass_ws_client):
     hass.states.async_set(
         "sensor.test",
         10,
-        attributes={"device_class": "temperature", "state_class": "measurement"},
+        attributes={
+            "device_class": "temperature",
+            "state_class": "measurement",
+            "unit_of_measurement": "°C",
+        },
     )
     await hass.async_block_till_done()
 

tests/components/recorder/test_statistics.py

@@ -9,6 +9,7 @@ from homeassistant.components.recorder import history
 from homeassistant.components.recorder.const import DATA_INSTANCE
 from homeassistant.components.recorder.models import process_timestamp_to_utc_isoformat
 from homeassistant.components.recorder.statistics import statistics_during_period
+from homeassistant.const import TEMP_CELSIUS
 from homeassistant.setup import setup_component
 import homeassistant.util.dt as dt_util
 
@@ -53,7 +54,11 @@ def record_states(hass):
     sns1 = "sensor.test1"
     sns2 = "sensor.test2"
     sns3 = "sensor.test3"
-    sns1_attr = {"device_class": "temperature", "state_class": "measurement"}
+    sns1_attr = {
+        "device_class": "temperature",
+        "state_class": "measurement",
+        "unit_of_measurement": TEMP_CELSIUS,
+    }
     sns2_attr = {"device_class": "temperature"}
     sns3_attr = {}
 

tests/components/sensor/test_recorder.py

@@ -9,7 +9,7 @@ from homeassistant.components.recorder import history
 from homeassistant.components.recorder.const import DATA_INSTANCE
 from homeassistant.components.recorder.models import process_timestamp_to_utc_isoformat
 from homeassistant.components.recorder.statistics import statistics_during_period
-from homeassistant.const import STATE_UNAVAILABLE
+from homeassistant.const import STATE_UNAVAILABLE, TEMP_CELSIUS
 from homeassistant.setup import setup_component
 import homeassistant.util.dt as dt_util
 
@@ -324,7 +324,11 @@ def record_states(hass):
     sns1 = "sensor.test1"
     sns2 = "sensor.test2"
     sns3 = "sensor.test3"
-    sns1_attr = {"device_class": "temperature", "state_class": "measurement"}
+    sns1_attr = {
+        "device_class": "temperature",
+        "state_class": "measurement",
+        "unit_of_measurement": TEMP_CELSIUS,
+    }
     sns2_attr = {"device_class": "temperature"}
     sns3_attr = {}
 
@@ -466,7 +470,11 @@ def record_states_partially_unavailable(hass):
     sns1 = "sensor.test1"
     sns2 = "sensor.test2"
     sns3 = "sensor.test3"
-    sns1_attr = {"device_class": "temperature", "state_class": "measurement"}
+    sns1_attr = {
+        "device_class": "temperature",
+        "state_class": "measurement",
+        "unit_of_measurement": TEMP_CELSIUS,
+    }
     sns2_attr = {"device_class": "temperature"}
     sns3_attr = {}
 

tests/util/test_temperature.py

@@ -0,0 +1,84 @@
+"""Test Home Assistant temperature utility functions."""
+import pytest
+
+from homeassistant.const import TEMP_CELSIUS, TEMP_FAHRENHEIT, TEMP_KELVIN
+import homeassistant.util.temperature as temperature_util
+
+INVALID_SYMBOL = "bob"
+VALID_SYMBOL = TEMP_CELSIUS
+
+
+def test_convert_same_unit():
+    """Test conversion from any unit to same unit."""
+    assert temperature_util.convert(2, TEMP_CELSIUS, TEMP_CELSIUS) == 2
+    assert temperature_util.convert(3, TEMP_FAHRENHEIT, TEMP_FAHRENHEIT) == 3
+    assert temperature_util.convert(4, TEMP_KELVIN, TEMP_KELVIN) == 4
+
+
+def test_convert_invalid_unit():
+    """Test exception is thrown for invalid units."""
+    with pytest.raises(ValueError):
+        temperature_util.convert(5, INVALID_SYMBOL, VALID_SYMBOL)
+
+    with pytest.raises(ValueError):
+        temperature_util.convert(5, VALID_SYMBOL, INVALID_SYMBOL)
+
+
+def test_convert_nonnumeric_value():
+    """Test exception is thrown for nonnumeric type."""
+    with pytest.raises(TypeError):
+        temperature_util.convert("a", TEMP_CELSIUS, TEMP_FAHRENHEIT)
+
+
+def test_convert_from_celsius():
+    """Test conversion from C to other units."""
+    celsius = 100
+    assert temperature_util.convert(
+        celsius, TEMP_CELSIUS, TEMP_FAHRENHEIT
+    ) == pytest.approx(212.0)
+    assert temperature_util.convert(
+        celsius, TEMP_CELSIUS, TEMP_KELVIN
+    ) == pytest.approx(373.15)
+    # Interval
+    assert temperature_util.convert(
+        celsius, TEMP_CELSIUS, TEMP_FAHRENHEIT, True
+    ) == pytest.approx(180.0)
+    assert temperature_util.convert(
+        celsius, TEMP_CELSIUS, TEMP_KELVIN, True
+    ) == pytest.approx(100)
+
+
+def test_convert_from_fahrenheit():
+    """Test conversion from F to other units."""
+    fahrenheit = 100
+    assert temperature_util.convert(
+        fahrenheit, TEMP_FAHRENHEIT, TEMP_CELSIUS
+    ) == pytest.approx(37.77777777777778)
+    assert temperature_util.convert(
+        fahrenheit, TEMP_FAHRENHEIT, TEMP_KELVIN
+    ) == pytest.approx(310.92777777777775)
+    # Interval
+    assert temperature_util.convert(
+        fahrenheit, TEMP_FAHRENHEIT, TEMP_CELSIUS, True
+    ) == pytest.approx(55.55555555555556)
+    assert temperature_util.convert(
+        fahrenheit, TEMP_FAHRENHEIT, TEMP_KELVIN, True
+    ) == pytest.approx(55.55555555555556)
+
+
+def test_convert_from_kelvin():
+    """Test conversion from K to other units."""
+    kelvin = 100
+    assert temperature_util.convert(kelvin, TEMP_KELVIN, TEMP_CELSIUS) == pytest.approx(
+        -173.15
+    )
+    assert temperature_util.convert(
+        kelvin, TEMP_KELVIN, TEMP_FAHRENHEIT
+    ) == pytest.approx(-279.66999999999996)
+    # Interval
+    assert temperature_util.convert(
+        kelvin, TEMP_KELVIN, TEMP_FAHRENHEIT, True
+    ) == pytest.approx(180.0)
+    assert temperature_util.convert(
+        kelvin, TEMP_KELVIN, TEMP_KELVIN, True
+    ) == pytest.approx(100)

tests/util/test_unit_system.py

@@ -106,7 +106,7 @@ def test_temperature_same_unit():
 def test_temperature_unknown_unit():
     """Test no conversion happens if unknown unit."""
     with pytest.raises(ValueError):
-        METRIC_SYSTEM.temperature(5, "K")
+        METRIC_SYSTEM.temperature(5, "abc")
 
 
 def test_temperature_to_metric():