fix: Home Assistant: apply expose-level Home Assistant discovery metadata (#32380)

lib/extension/homeassistant.ts

@@ -335,6 +335,29 @@ const featurePropertyWithoutEndpoint = (feature: zhc.Feature): string => {
     return feature.property;
 };
 
+const applyHomeAssistantExposeMetadata = (payload: KeyValue, homeAssistant: zhc.Expose["homeassistant"]): void => {
+    const metadata = homeAssistant as KeyValue | undefined;
+    if (!metadata) {
+        return;
+    }
+
+    if (typeof metadata.entityCategory === "string") {
+        payload.entity_category = metadata.entityCategory;
+    }
+
+    if (typeof metadata.deviceClass === "string") {
+        payload.device_class = metadata.deviceClass;
+    }
+
+    if (typeof metadata.enabledByDefault === "boolean") {
+        payload.enabled_by_default = metadata.enabledByDefault;
+    }
+
+    if (typeof metadata.icon === "string") {
+        payload.icon = metadata.icon;
+    }
+};
+
 /**
  * This class handles the bridge entity configuration for Home Assistant Discovery.
  */
@@ -1344,6 +1367,8 @@ export class HomeAssistant extends Extension {
         }
 
         for (const entry of discoveryEntries) {
+            applyHomeAssistantExposeMetadata(entry.discovery_payload, firstExpose.homeassistant);
+
             // If a sensor has entity category `config`, then change
             // it to `diagnostic`. Sensors have no input, so can't be configured.
             // https://github.com/Koenkk/zigbee2mqtt/pull/19474

test/extensions/homeassistant.test.ts

@@ -174,6 +174,40 @@ describe("Extension: HomeAssistant", () => {
         }
     });
 
+    it("Should apply expose-level Home Assistant discovery metadata", () => {
+        const createDevice = (exposes: zhc.Expose[]): Device =>
+            ({
+                definition: {},
+                isDevice: (): boolean => true,
+                isGroup: (): boolean => false,
+                endpoint: () => undefined,
+                options: {},
+                exposes: (): zhc.Expose[] => exposes,
+                zh: {endpoints: []},
+            }) as Device;
+
+        const voltageExpose = new zhc.Numeric("voltage", zhc.access.STATE).withUnit("V");
+        Object.assign(voltageExpose, {
+            homeassistant: {
+                type: "valve",
+                entityCategory: "diagnostic",
+                deviceClass: "voltage",
+                enabledByDefault: false,
+                icon: "mdi:flash",
+            },
+        });
+
+        // @ts-expect-error private
+        const configs = extension.getConfigs(createDevice([voltageExpose]));
+        expect(configs.find((config) => config.object_id === "voltage")?.discovery_payload).toMatchObject({
+            device_class: "voltage",
+            enabled_by_default: false,
+            entity_category: "diagnostic",
+            icon: "mdi:flash",
+        });
+        expect(configs.find((config) => config.object_id === "voltage")?.discovery_payload).not.toHaveProperty("type");
+    });
+
     it("Should discover devices and groups", async () => {
         settings.set(["homeassistant", "experimental_event_entities"], true);
         settings.set(["groups", "9", "homeassistant"], {name: "HA Discovery Group", icon: "mdi:lightbulb-group"});