feat: 🎸 Ember IPC service rejects when receiving error instance

ui/desktop/app/services/ipc.js

@@ -59,10 +59,14 @@ export class IPCRequest {
     this.payload = payload;
     this.origin = window?.location?.origin;
     this.#channel = new MessageChannel();
-    this.#promise = new Promise((resolve /*, reject*/) => {
+    this.#promise = new Promise((resolve, reject) => {
       this.#channel.port1.onmessage = (event) => {
         this.close();
-        resolve(event.data);
+        if (event.data instanceof Error) {
+          reject(JSON.parse(event.data.message));
+        } else {
+          resolve(event.data);
+        }
       };
     });
     window.postMessage(

ui/desktop/tests/unit/services/ipc-test.js

@@ -53,4 +53,26 @@ module('Unit | Service | ipc', function (hooks) {
       test: 42,
     });
   });
+
+  test('IPCRequests reject if receiving an Error instance, where the rejection value is the parsed JSON Error message', async (assert) => {
+    assert.expect(1);
+    const stringifiedPayload = JSON.stringify({
+      foo: 'bar',
+      test: 42
+    });
+    const myWindow = {
+      postMessage(request, origin, [port]) {
+        // Post back an error on the response port
+        port.postMessage(new Error(stringifiedPayload));
+      }
+    };
+    try {
+      await new IPCRequest('hello', 'world', myWindow);
+    } catch (e) {
+      assert.deepEqual(e, {
+        foo: 'bar',
+        test: 42,
+      });
+    }
+  });
 });