fix: auto-start and focus desktop window

src/desktop-electron/app.ts

@@ -1,25 +1,78 @@
 import { app } from "electron";
+import path from "node:path";
 import { registerElectronDesktopBridge } from "./main";
 import { resolveDesktopStartUrl } from "./startup";
 import { findRepoRoot } from "../installer-core/repo";
 
+export interface DesktopStartupWindow {
+  show(): void;
+  focus(): void;
+}
+
+export interface DesktopStartupApp {
+  dock?: {
+    show(): void;
+  };
+  focus(options?: { steal?: boolean }): void;
+}
+
+export function focusDesktopWindow(window: DesktopStartupWindow, desktopApp: DesktopStartupApp = app): void {
+  try {
+    desktopApp.dock?.show();
+  } catch {
+    // Ignore dock activation failures on non-macOS runtimes.
+  }
+
+  window.show();
+  window.focus();
+
+  try {
+    desktopApp.focus({ steal: true });
+  } catch {
+    desktopApp.focus();
+  }
+}
+
+export function shouldAutoStartDesktopApp(
+  argv: string[] = process.argv,
+  filename: string = __filename,
+  electronRuntime: string | undefined = process.versions?.electron,
+): boolean {
+  if (!electronRuntime) {
+    return false;
+  }
+
+  const entryArg = argv[1];
+  if (!entryArg) {
+    return false;
+  }
+
+  return path.resolve(entryArg) === path.resolve(filename);
+}
+
 export async function startElectronDesktopApp(): Promise<void> {
+  await app.whenReady();
   const repoRoot = findRepoRoot(__dirname);
   const startUrl = resolveDesktopStartUrl(repoRoot, process.env);
   const desktopBridge = await registerElectronDesktopBridge({
     repoRoot,
     startUrl,
   });
 
-  await desktopBridge.createWindow();
+  const window = await desktopBridge.createWindow();
+  focusDesktopWindow(window);
 
   app.on("window-all-closed", async () => {
     await desktopBridge.dispose();
     app.quit();
   });
+
+  app.on("activate", () => {
+    focusDesktopWindow(window);
+  });
 }
 
-if (require.main === module) {
+if (shouldAutoStartDesktopApp()) {
   void startElectronDesktopApp().catch((error) => {
     console.error("[desktop] Electron startup failed.", error);
     app.quit();

src/types/electron.d.ts

@@ -38,6 +38,8 @@ declare module "electron" {
   export class BrowserWindow {
     constructor(options?: BrowserWindowConstructorOptions);
     loadURL(url: string): Promise<void>;
+    show(): void;
+    focus(): void;
     webContents: WebContents;
   }
 
@@ -52,6 +54,10 @@ declare module "electron" {
     on(event: "window-all-closed" | "activate", listener: () => void): void;
     getVersion(): string;
     isPackaged: boolean;
+    focus(options?: { steal?: boolean }): void;
+    dock?: {
+      show(): void;
+    };
     quit(): void;
   };
 

tests/installer/desktop-preview-startup.test.ts

@@ -4,6 +4,7 @@ import fs from "node:fs";
 import path from "node:path";
 import { fileURLToPath } from "node:url";
 import { installDesktopLoadDiagnostics, resolveDesktopStartUrl } from "../../src/desktop-electron/startup";
+import { focusDesktopWindow, shouldAutoStartDesktopApp } from "../../src/desktop-electron/app";
 
 interface FakeWebContents {
   on(
@@ -84,3 +85,37 @@ test("desktop load diagnostics present a readable fallback when renderer load fa
   assert.match(decoded, /file:\/\/\/broken\/index\.html/);
   assert.match(errors.join("\n"), /ERR_FILE_NOT_FOUND/);
 });
+
+test("desktop startup explicitly surfaces the first Electron window", () => {
+  const calls: string[] = [];
+  const fakeWindow = {
+    show() {
+      calls.push("window.show");
+    },
+    focus() {
+      calls.push("window.focus");
+    },
+  };
+  const fakeApp = {
+    dock: {
+      show() {
+        calls.push("dock.show");
+      },
+    },
+    focus(options?: { steal?: boolean }) {
+      calls.push(`app.focus:${options?.steal === true ? "steal" : "default"}`);
+    },
+  };
+
+  focusDesktopWindow(fakeWindow, fakeApp);
+
+  assert.deepEqual(calls, ["dock.show", "window.show", "window.focus", "app.focus:steal"]);
+});
+
+test("desktop app entrypoint auto-starts only for Electron script execution", () => {
+  const filename = "/workspace/dist/src/desktop-electron/app.js";
+
+  assert.equal(shouldAutoStartDesktopApp(["/electron", filename], filename, "35.1.4"), true);
+  assert.equal(shouldAutoStartDesktopApp(["/node", "/workspace/test-runner.js"], filename, undefined), false);
+  assert.equal(shouldAutoStartDesktopApp(["/electron"], filename, "35.1.4"), false);
+});