must support imperial as well

homeassistant/components/sensor/const.py

@@ -351,7 +351,7 @@ class SensorDeviceClass(StrEnum):
 
     Unit of measurement: `SPEED_*` units or `UnitOfVolumetricFlux`
     - SI /metric: `mm/d`, `mm/h`, `m/s`, `km/h`, `mm/s`
-    - USCS / imperial: `in/d`, `in/h`, `ft/s`, `mph`
+    - USCS / imperial: `in/d`, `in/h`, `in/s`, `ft/s`, `mph`
     - Nautical: `kn`
     - Beaufort: `Beaufort`
     """

homeassistant/const.py

@@ -1266,6 +1266,7 @@ class UnitOfSpeed(StrEnum):
 
     BEAUFORT = "Beaufort"
     FEET_PER_SECOND = "ft/s"
+    INCHES_PER_SECOND = "in/s"
     METERS_PER_SECOND = "m/s"
     KILOMETERS_PER_HOUR = "km/h"
     KNOTS = "kn"

homeassistant/util/unit_conversion.py

@@ -333,6 +333,7 @@ class SpeedConverter(BaseUnitConverter):
         UnitOfVolumetricFlux.MILLIMETERS_PER_DAY: _DAYS_TO_SECS / _MM_TO_M,
         UnitOfVolumetricFlux.MILLIMETERS_PER_HOUR: _HRS_TO_SECS / _MM_TO_M,
         UnitOfSpeed.FEET_PER_SECOND: 1 / _FOOT_TO_M,
+        UnitOfSpeed.INCHES_PER_SECOND: 1 / _IN_TO_M,
         UnitOfSpeed.KILOMETERS_PER_HOUR: _HRS_TO_SECS / _KM_TO_M,
         UnitOfSpeed.KNOTS: _HRS_TO_SECS / _NAUTICAL_MILE_TO_M,
         UnitOfSpeed.METERS_PER_SECOND: 1,
@@ -345,6 +346,7 @@ class SpeedConverter(BaseUnitConverter):
         UnitOfVolumetricFlux.INCHES_PER_HOUR,
         UnitOfVolumetricFlux.MILLIMETERS_PER_DAY,
         UnitOfVolumetricFlux.MILLIMETERS_PER_HOUR,
+        UnitOfSpeed.INCHES_PER_SECOND,
         UnitOfSpeed.FEET_PER_SECOND,
         UnitOfSpeed.KILOMETERS_PER_HOUR,
         UnitOfSpeed.KNOTS,

homeassistant/util/unit_system.py

@@ -260,6 +260,7 @@ def _deprecated_unit_system(value: str) -> str:
         ("pressure", UnitOfPressure.INHG): UnitOfPressure.HPA,
         # Convert non-metric speeds except knots to km/h
         ("speed", UnitOfSpeed.FEET_PER_SECOND): UnitOfSpeed.KILOMETERS_PER_HOUR,
+        ("speed", UnitOfSpeed.INCHES_PER_SECOND): UnitOfSpeed.MILLIMETERS_PER_SECOND,
         ("speed", UnitOfSpeed.MILES_PER_HOUR): UnitOfSpeed.KILOMETERS_PER_HOUR,
         (
             "speed",
@@ -332,6 +333,7 @@ def _deprecated_unit_system(value: str) -> str:
         ("pressure", UnitOfPressure.MMHG): UnitOfPressure.INHG,
         # Convert non-USCS speeds, except knots, to mph
         ("speed", UnitOfSpeed.METERS_PER_SECOND): UnitOfSpeed.MILES_PER_HOUR,
+        ("speed", UnitOfSpeed.MILLIMETERS_PER_SECOND): UnitOfSpeed.INCHES_PER_SECOND,
         ("speed", UnitOfSpeed.KILOMETERS_PER_HOUR): UnitOfSpeed.MILES_PER_HOUR,
         (
             "speed",

tests/components/sensor/test_websocket_api.py

@@ -36,6 +36,7 @@ async def test_device_class_units(
             "ft/s",
             "in/d",
             "in/h",
+            "in/s",
             "km/h",
             "kn",
             "m/s",

tests/util/test_unit_conversion.py

@@ -426,6 +426,13 @@
             5000,
             UnitOfSpeed.MILLIMETERS_PER_SECOND,
         ),
+        # 5 m/s ÷ 0.0254 = 196.8503937 in/s
+        (
+            5,
+            UnitOfSpeed.METERS_PER_SECOND,
+            5 / 0.0254,
+            UnitOfSpeed.INCHES_PER_SECOND,
+        ),
         # 5000 in/h / 39.3701 in/m / 3600 s/h = 0.03528 m/s
         (
             5000,