From b07e1281da06ac006cd84713fe719238bcc5145f Mon Sep 17 00:00:00 2001
From: Erik Montnemery <erik@montnemery.com>
Date: Tue, 25 Oct 2022 14:53:59 +0200
Subject: [PATCH] Add rules for converting speeds (#80943)

* Add rules for converting speeds

* Update metoffice wind speed sensors to prefer mph

* Don't convert speeds measured in knots
---
 homeassistant/components/metoffice/sensor.py |  2 ++
 homeassistant/util/unit_system.py            |  8 ++++++++
 tests/util/test_unit_system.py               | 20 ++++++++++++++++++++
 3 files changed, 30 insertions(+)

diff --git a/homeassistant/components/metoffice/sensor.py b/homeassistant/components/metoffice/sensor.py
index 82a6712af9097d..ef9643be96ae05 100644
--- a/homeassistant/components/metoffice/sensor.py
+++ b/homeassistant/components/metoffice/sensor.py
@@ -83,6 +83,7 @@
         key="wind_speed",
         name="Wind speed",
         native_unit_of_measurement=SPEED_MILES_PER_HOUR,
+        suggested_unit_of_measurement=SPEED_MILES_PER_HOUR,
         device_class=SensorDeviceClass.SPEED,
         icon="mdi:weather-windy",
         entity_registry_enabled_default=True,
@@ -98,6 +99,7 @@
         key="wind_gust",
         name="Wind gust",
         native_unit_of_measurement=SPEED_MILES_PER_HOUR,
+        suggested_unit_of_measurement=SPEED_MILES_PER_HOUR,
         device_class=SensorDeviceClass.SPEED,
         icon="mdi:weather-windy",
         entity_registry_enabled_default=False,
diff --git a/homeassistant/util/unit_system.py b/homeassistant/util/unit_system.py
index 72779fe8c8405e..9e1c20022b221e 100644
--- a/homeassistant/util/unit_system.py
+++ b/homeassistant/util/unit_system.py
@@ -27,6 +27,8 @@
     PRESSURE,
     PRESSURE_PA,
     PRESSURE_PSI,
+    SPEED_FEET_PER_SECOND,
+    SPEED_KILOMETERS_PER_HOUR,
     SPEED_METERS_PER_SECOND,
     SPEED_MILES_PER_HOUR,
     TEMP_CELSIUS,
@@ -268,6 +270,9 @@ def _deprecated_unit_system(value: str) -> str:
         ("distance", LENGTH_INCHES): LENGTH_MILLIMETERS,
         ("distance", LENGTH_MILES): LENGTH_KILOMETERS,
         ("distance", LENGTH_YARD): LENGTH_METERS,
+        # Convert non-metric speeds except knots to km/h
+        ("speed", SPEED_FEET_PER_SECOND): SPEED_KILOMETERS_PER_HOUR,
+        ("speed", SPEED_MILES_PER_HOUR): SPEED_KILOMETERS_PER_HOUR,
     },
     length=LENGTH_KILOMETERS,
     mass=MASS_GRAMS,
@@ -286,6 +291,9 @@ def _deprecated_unit_system(value: str) -> str:
         ("distance", LENGTH_KILOMETERS): LENGTH_MILES,
         ("distance", LENGTH_METERS): LENGTH_FEET,
         ("distance", LENGTH_MILLIMETERS): LENGTH_INCHES,
+        # Convert non-USCS speeds except knots to mph
+        ("speed", SPEED_METERS_PER_SECOND): SPEED_MILES_PER_HOUR,
+        ("speed", SPEED_KILOMETERS_PER_HOUR): SPEED_MILES_PER_HOUR,
     },
     length=LENGTH_MILES,
     mass=MASS_POUNDS,
diff --git a/tests/util/test_unit_system.py b/tests/util/test_unit_system.py
index dd584a8dd3b8a6..82d13ae6baa08f 100644
--- a/tests/util/test_unit_system.py
+++ b/tests/util/test_unit_system.py
@@ -16,7 +16,11 @@
     MASS_GRAMS,
     PRESSURE,
     PRESSURE_PA,
+    SPEED_FEET_PER_SECOND,
+    SPEED_KILOMETERS_PER_HOUR,
+    SPEED_KNOTS,
     SPEED_METERS_PER_SECOND,
+    SPEED_MILES_PER_HOUR,
     TEMP_CELSIUS,
     TEMPERATURE,
     VOLUME,
@@ -384,18 +388,34 @@ def test_get_unit_system_invalid(key: str) -> None:
 @pytest.mark.parametrize(
     "unit_system, device_class, original_unit, state_unit",
     (
+        # Test distance conversion
         (METRIC_SYSTEM, "distance", LENGTH_FEET, LENGTH_METERS),
         (METRIC_SYSTEM, "distance", LENGTH_INCHES, LENGTH_MILLIMETERS),
         (METRIC_SYSTEM, "distance", LENGTH_MILES, LENGTH_KILOMETERS),
         (METRIC_SYSTEM, "distance", LENGTH_YARD, LENGTH_METERS),
         (METRIC_SYSTEM, "distance", LENGTH_KILOMETERS, None),
         (METRIC_SYSTEM, "distance", "very_long", None),
+        # Test speed conversion
+        (METRIC_SYSTEM, "speed", SPEED_FEET_PER_SECOND, SPEED_KILOMETERS_PER_HOUR),
+        (METRIC_SYSTEM, "speed", SPEED_MILES_PER_HOUR, SPEED_KILOMETERS_PER_HOUR),
+        (METRIC_SYSTEM, "speed", SPEED_KILOMETERS_PER_HOUR, None),
+        (METRIC_SYSTEM, "speed", SPEED_KNOTS, None),
+        (METRIC_SYSTEM, "speed", SPEED_METERS_PER_SECOND, None),
+        (METRIC_SYSTEM, "speed", "very_fast", None),
+        # Test distance conversion
         (US_CUSTOMARY_SYSTEM, "distance", LENGTH_CENTIMETERS, LENGTH_INCHES),
         (US_CUSTOMARY_SYSTEM, "distance", LENGTH_KILOMETERS, LENGTH_MILES),
         (US_CUSTOMARY_SYSTEM, "distance", LENGTH_METERS, LENGTH_FEET),
         (US_CUSTOMARY_SYSTEM, "distance", LENGTH_MILLIMETERS, LENGTH_INCHES),
         (US_CUSTOMARY_SYSTEM, "distance", LENGTH_MILES, None),
         (US_CUSTOMARY_SYSTEM, "distance", "very_long", None),
+        # Test speed conversion
+        (US_CUSTOMARY_SYSTEM, "speed", SPEED_METERS_PER_SECOND, SPEED_MILES_PER_HOUR),
+        (US_CUSTOMARY_SYSTEM, "speed", SPEED_KILOMETERS_PER_HOUR, SPEED_MILES_PER_HOUR),
+        (US_CUSTOMARY_SYSTEM, "speed", SPEED_FEET_PER_SECOND, None),
+        (US_CUSTOMARY_SYSTEM, "speed", SPEED_KNOTS, None),
+        (US_CUSTOMARY_SYSTEM, "speed", SPEED_MILES_PER_HOUR, None),
+        (US_CUSTOMARY_SYSTEM, "speed", "very_fast", None),
     ),
 )
 def test_get_converted_unit(