test: cover frontend install prompt dismissal

frontend/src/app/components/global_ui/InstallPrompt.tsx

@@ -8,11 +8,24 @@ interface BeforeInstallPromptEvent extends Event {
   userChoice: Promise<{ outcome: "accepted" | "dismissed" }>;
 }
 
+export const DISMISSED_STORAGE_KEY = "install-prompt-dismissed";
+
+export const isInstallPromptDismissed = (): boolean => {
+  if (typeof window === "undefined") return false;
+  try {
+    return window.localStorage.getItem(DISMISSED_STORAGE_KEY) === "true";
+  } catch {
+    return false;
+  }
+};
+
 export function InstallPrompt() {
   const [deferredPrompt, setDeferredPrompt] = useState<BeforeInstallPromptEvent | null>(null);
   const [dismissed, setDismissed] = useState(false);
 
   useEffect(() => {
+    setDismissed(isInstallPromptDismissed());
+
     const handler = (e: Event) => {
       e.preventDefault();
       setDeferredPrompt(e as BeforeInstallPromptEvent);
@@ -25,13 +38,22 @@ export function InstallPrompt() {
   if (!deferredPrompt || dismissed) return null;
 
   const handleInstall = async () => {
-    deferredPrompt.prompt();
+    await deferredPrompt.prompt();
     const { outcome } = await deferredPrompt.userChoice;
     if (outcome === "accepted") {
       setDeferredPrompt(null);
     }
   };
 
+  const handleDismiss = () => {
+    setDismissed(true);
+    try {
+      window.localStorage.setItem(DISMISSED_STORAGE_KEY, "true");
+    } catch {
+      // localStorage may be unavailable; dismissal still applies for this session.
+    }
+  };
+
   return (
     <div className="fixed bottom-4 right-4 z-50 flex items-center gap-3 rounded-xl border border-indigo-200 bg-indigo-50 px-4 py-3 shadow-lg dark:border-indigo-900/50 dark:bg-indigo-950/40">
       <Download className="h-5 w-5 text-indigo-600 dark:text-indigo-400" />
@@ -47,7 +69,7 @@ export function InstallPrompt() {
       </button>
       <button
         type="button"
-        onClick={() => setDismissed(true)}
+        onClick={handleDismiss}
         className="text-indigo-400 transition hover:text-indigo-600"
         aria-label="Dismiss install prompt"
       >

frontend/src/app/components/global_ui/__tests__/InstallPrompt.test.tsx

@@ -0,0 +1,129 @@
+import { act, fireEvent, render, screen, waitFor } from "@testing-library/react";
+import { InstallPrompt, DISMISSED_STORAGE_KEY } from "../InstallPrompt";
+
+type Outcome = "accepted" | "dismissed";
+
+interface MockBeforeInstallPromptEvent extends Event {
+  prompt: jest.Mock<Promise<void>, []>;
+  userChoice: Promise<{ outcome: Outcome }>;
+}
+
+const PROMPT_TEXT = /Install RemitLend for offline access/i;
+
+const createInstallEvent = (outcome: Outcome): MockBeforeInstallPromptEvent => {
+  const event = new Event("beforeinstallprompt", {
+    cancelable: true,
+  }) as MockBeforeInstallPromptEvent;
+  event.prompt = jest.fn(() => Promise.resolve());
+  event.userChoice = Promise.resolve({ outcome });
+  return event;
+};
+
+const dispatchBeforeInstallPrompt = (outcome: Outcome): MockBeforeInstallPromptEvent => {
+  const event = createInstallEvent(outcome);
+  act(() => {
+    window.dispatchEvent(event);
+  });
+  return event;
+};
+
+const installButton = () => screen.getByRole("button", { name: /^install$/i });
+const dismissButton = () => screen.getByRole("button", { name: /dismiss install prompt/i });
+
+describe("InstallPrompt", () => {
+  beforeEach(() => {
+    window.localStorage.clear();
+  });
+
+  afterEach(() => {
+    window.localStorage.clear();
+    jest.restoreAllMocks();
+  });
+
+  it("renders nothing when the browser does not support install prompts", () => {
+    const { container } = render(<InstallPrompt />);
+
+    expect(container).toBeEmptyDOMElement();
+    expect(screen.queryByText(PROMPT_TEXT)).not.toBeInTheDocument();
+  });
+
+  it("shows the prompt when the browser fires beforeinstallprompt", () => {
+    render(<InstallPrompt />);
+
+    dispatchBeforeInstallPrompt("accepted");
+
+    expect(screen.getByText(PROMPT_TEXT)).toBeInTheDocument();
+    expect(installButton()).toBeInTheDocument();
+  });
+
+  it("prevents the default browser behavior for the install event", () => {
+    render(<InstallPrompt />);
+
+    const event = dispatchBeforeInstallPrompt("accepted");
+
+    expect(event.defaultPrevented).toBe(true);
+  });
+
+  it("calls prompt and removes the prompt when the user accepts", async () => {
+    render(<InstallPrompt />);
+
+    const event = dispatchBeforeInstallPrompt("accepted");
+
+    await act(async () => {
+      fireEvent.click(installButton());
+    });
+
+    expect(event.prompt).toHaveBeenCalledTimes(1);
+    await waitFor(() => expect(screen.queryByText(PROMPT_TEXT)).not.toBeInTheDocument());
+  });
+
+  it("keeps the prompt visible when the user dismisses the native install dialog", async () => {
+    render(<InstallPrompt />);
+
+    const event = dispatchBeforeInstallPrompt("dismissed");
+
+    await act(async () => {
+      fireEvent.click(installButton());
+    });
+
+    expect(event.prompt).toHaveBeenCalledTimes(1);
+    expect(screen.getByText(PROMPT_TEXT)).toBeInTheDocument();
+  });
+
+  it("hides the prompt when the user clicks the dismiss button", () => {
+    render(<InstallPrompt />);
+
+    dispatchBeforeInstallPrompt("accepted");
+    fireEvent.click(dismissButton());
+
+    expect(screen.queryByText(PROMPT_TEXT)).not.toBeInTheDocument();
+  });
+
+  it("persists the dismissal to localStorage", () => {
+    render(<InstallPrompt />);
+
+    dispatchBeforeInstallPrompt("accepted");
+    fireEvent.click(dismissButton());
+
+    expect(window.localStorage.getItem(DISMISSED_STORAGE_KEY)).toBe("true");
+  });
+
+  it("stays hidden on mount when a dismissal was previously persisted", () => {
+    window.localStorage.setItem(DISMISSED_STORAGE_KEY, "true");
+
+    render(<InstallPrompt />);
+
+    dispatchBeforeInstallPrompt("accepted");
+
+    expect(screen.queryByText(PROMPT_TEXT)).not.toBeInTheDocument();
+  });
+
+  it("removes the beforeinstallprompt listener on unmount", () => {
+    const removeSpy = jest.spyOn(window, "removeEventListener");
+    const { unmount } = render(<InstallPrompt />);
+
+    unmount();
+
+    expect(removeSpy).toHaveBeenCalledWith("beforeinstallprompt", expect.anything());
+  });
+});