Allow Sensor Units to be updated via Entity Registry

src/data/entity_registry.ts

@@ -41,6 +41,10 @@ export interface EntityRegistryEntryUpdateParams {
   disabled_by?: string | null;
   hidden_by: string | null;
   new_entity_id?: string;
+  options_domain?: string;
+  options?: {
+    unit_of_measurement?: string | null;
+  };
 }
 
 export const findBatteryEntity = (

src/panels/config/entities/entity-registry-settings.ts

@@ -83,6 +83,11 @@ const OVERRIDE_DEVICE_CLASSES = {
   ],
 };
 
+const OVERRIDE_SENSOR_UNITS = {
+  temperature: ["°C", "°F", "K"],
+  pressure: ["hPa", "Pa", "kPa", "bar", "cbar", "mbar", "mmHg", "inHg", "psi"],
+};
+
 @customElement("entity-registry-settings")
 export class EntityRegistrySettings extends SubscribeMixin(LitElement) {
   @property({ attribute: false }) public hass!: HomeAssistant;
@@ -107,6 +112,8 @@ export class EntityRegistrySettings extends SubscribeMixin(LitElement) {
 
   @state() private _helperConfigEntry?: ConfigEntry;
 
+  @state() private _unit_of_measurement?: string | null;
+
   @state() private _error?: string;
 
   @state() private _submitting?: boolean;
@@ -167,6 +174,13 @@ export class EntityRegistrySettings extends SubscribeMixin(LitElement) {
         : undefined;
 
     const domain = computeDomain(this.entry.entity_id);
+
+    if (domain === "sensor") {
+      const stateObj: HassEntity | undefined =
+        this.hass.states[this.entry.entity_id];
+      this._unit_of_measurement = stateObj?.attributes?.unit_of_measurement;
+    }
+
     const deviceClasses: string[][] = OVERRIDE_DEVICE_CLASSES[domain];
 
     if (!deviceClasses) {
@@ -269,6 +283,30 @@ export class EntityRegistrySettings extends SubscribeMixin(LitElement) {
               </ha-select>
             `
           : ""}
+        ${this._deviceClass &&
+        stateObj.attributes.unit_of_measurement &&
+        OVERRIDE_SENSOR_UNITS[this._deviceClass]?.includes(
+          stateObj.attributes.unit_of_measurement
+        )
+          ? html`
+              <ha-select
+                .label=${this.hass.localize(
+                  "ui.dialogs.entity_registry.editor.unit_of_measurement"
+                )}
+                .value=${stateObj.attributes.unit_of_measurement}
+                naturalMenuWidth
+                fixedMenuPosition
+                @selected=${this._unitChanged}
+                @closed=${stopPropagation}
+              >
+                ${OVERRIDE_SENSOR_UNITS[this._deviceClass].map(
+                  (unit: string) => html`
+                    <mwc-list-item .value=${unit}>${unit}</mwc-list-item>
+                  `
+                )}
+              </ha-select>
+            `
+          : ""}
         <ha-textfield
           error-message="Domain needs to stay the same"
           .value=${this._entityId}
@@ -469,6 +507,11 @@ export class EntityRegistrySettings extends SubscribeMixin(LitElement) {
     this._deviceClass = ev.target.value;
   }
 
+  private _unitChanged(ev): void {
+    this._error = undefined;
+    this._unit_of_measurement = ev.target.value;
+  }
+
   private _areaPicked(ev: CustomEvent) {
     this._error = undefined;
     this._areaId = ev.detail.value;
@@ -509,6 +552,11 @@ export class EntityRegistrySettings extends SubscribeMixin(LitElement) {
       device_class: this._deviceClass || null,
       new_entity_id: this._entityId.trim(),
     };
+
+    const stateObj: HassEntity | undefined =
+      this.hass.states[this.entry.entity_id];
+    const domain = computeDomain(this.entry.entity_id);
+
     if (
       this.entry.disabled_by !== this._disabledBy &&
       (this._disabledBy === null || this._disabledBy === "user")
@@ -521,6 +569,13 @@ export class EntityRegistrySettings extends SubscribeMixin(LitElement) {
     ) {
       params.hidden_by = this._hiddenBy;
     }
+    if (
+      domain === "sensor" &&
+      stateObj?.attributes?.unit_of_measurement !== this._unit_of_measurement
+    ) {
+      params.options_domain = "sensor";
+      params.options = { unit_of_measurement: this._unit_of_measurement };
+    }
     try {
       const result = await updateEntityRegistryEntry(
         this.hass!,

src/translations/en.json

@@ -784,6 +784,7 @@
           "icon": "Icon",
           "icon_error": "Icons should be in the format 'prefix:iconname', e.g. 'mdi:home'",
           "entity_id": "Entity ID",
+          "unit_of_measurement": "Unit of Measurement",
           "device_class": "Show as",
           "device_classes": {
             "binary_sensor": {