Deprecate name property of unit system (#80257)

homeassistant/core.py

@@ -2015,7 +2015,9 @@ class Config:
             "latitude": self.latitude,
             "longitude": self.longitude,
             "elevation": self.elevation,
-            "unit_system": self.units.name,
+            # We don't want any components to use the name of the unit system
+            # so we are using the private attribute here
+            "unit_system": self.units._name,  # pylint: disable=protected-access
             "location_name": self.location_name,
             "time_zone": self.time_zone,
             "external_url": self.external_url,

homeassistant/util/unit_system.py

@@ -31,6 +31,7 @@ from homeassistant.const import (
     VOLUME_LITERS,
     WIND_SPEED,
 )
+from homeassistant.helpers.frame import report
 
 from .unit_conversion import (
     DistanceConverter,
@@ -107,7 +108,7 @@ class UnitSystem:
         if errors:
             raise ValueError(errors)
 
-        self.name = name
+        self._name = name
         self.accumulated_precipitation_unit = accumulated_precipitation
         self.temperature_unit = temperature
         self.length_unit = length
@@ -116,10 +117,21 @@ class UnitSystem:
         self.volume_unit = volume
         self.wind_speed_unit = wind_speed
 
+    @property
+    def name(self) -> str:
+        """Return the name of the unit system."""
+        report(
+            "accesses the `name` property of the unit system. "
+            "This is deprecated and will stop working in Home Assistant 2023.1. "
+            "Please adjust to use instance check instead.",
+            error_if_core=False,
+        )
+        return self._name
+
     @property
     def is_metric(self) -> bool:
         """Determine if this is the metric unit system."""
-        return self.name == CONF_UNIT_SYSTEM_METRIC
+        return self._name == CONF_UNIT_SYSTEM_METRIC
 
     def temperature(self, temperature: float, from_unit: str) -> float:
         """Convert the given temperature to this unit system."""

tests/util/test_unit_system.py

@@ -3,6 +3,8 @@ import pytest
 
 from homeassistant.const import (
     ACCUMULATED_PRECIPITATION,
+    CONF_UNIT_SYSTEM_IMPERIAL,
+    CONF_UNIT_SYSTEM_METRIC,
     LENGTH,
     LENGTH_KILOMETERS,
     LENGTH_METERS,
@@ -298,3 +300,21 @@ def test_is_metric():
     """Test the is metric flag."""
     assert METRIC_SYSTEM.is_metric
     assert not IMPERIAL_SYSTEM.is_metric
+
+
+@pytest.mark.parametrize(
+    "unit_system, expected_name",
+    [
+        (METRIC_SYSTEM, CONF_UNIT_SYSTEM_METRIC),
+        (IMPERIAL_SYSTEM, CONF_UNIT_SYSTEM_IMPERIAL),
+    ],
+)
+def test_deprecated_name(
+    caplog: pytest.LogCaptureFixture, unit_system: UnitSystem, expected_name: str
+) -> None:
+    """Test the name is deprecated."""
+    assert unit_system.name == expected_name
+    assert (
+        "Detected code that accesses the `name` property of the unit system."
+        in caplog.text
+    )