Add tests for guard components

- Created unit tests for `AuthGuard` and `PrivateGuard`
  components to ensure proper functionality.
- Verified that guards correctly redirect unauthorized users
  and allow access for authorized users.

client/src/guards/auth-guard.test.tsx

@@ -0,0 +1,62 @@
+import {
+  createMemoryRouter,
+  RouteObject,
+  RouterProvider,
+} from "react-router-dom";
+import { describe, it, expect, vi, Mock, beforeAll } from "vitest";
+import { render } from "@testing-library/react";
+
+import { useAuthStore } from "@/lib/stores/auth-store";
+import { AppRoutes } from "@/constants/routes";
+
+import AuthGuard from "./auth-guard";
+
+vi.mock("../lib/stores/auth-store.ts", () => ({
+  useAuthStore: vi.fn(),
+}));
+
+const routes: RouteObject[] = [
+  {
+    path: AppRoutes.Root,
+    element: <div>Root</div>,
+  },
+  {
+    element: <AuthGuard />,
+    children: [
+      {
+        path: AppRoutes.SignIn,
+        element: <div>Sign In</div>,
+      },
+    ],
+  },
+];
+
+describe("Auth Guard", () => {
+  let router: ReturnType<typeof createMemoryRouter>;
+
+  beforeAll(() => {
+    (useAuthStore as unknown as Mock).mockReturnValueOnce({
+      authorized: true,
+    });
+
+    router = createMemoryRouter(routes, {
+      initialEntries: [AppRoutes.SignIn],
+    });
+
+    render(<RouterProvider router={router} />);
+  });
+
+  it("redirects to the root page when authorized", () => {
+    expect(router.state.location.pathname).toBe(AppRoutes.Root);
+  });
+
+  it("renders the outlet when not authorized", () => {
+    (useAuthStore as unknown as Mock).mockReturnValueOnce({
+      authorized: false,
+    });
+
+    render(<RouterProvider router={router} />);
+
+    expect(router);
+  });
+});

client/src/guards/private-guard.test.tsx

@@ -0,0 +1,122 @@
+import {
+  createMemoryRouter,
+  RouteObject,
+  RouterProvider,
+} from "react-router-dom";
+import { describe, it, expect, vi, Mock } from "vitest";
+import { useQuery } from "@tanstack/react-query";
+import { render } from "@testing-library/react";
+import "@testing-library/jest-dom";
+
+import { useAuthStore } from "@/lib/stores/auth-store";
+import { AppRoutes } from "@/constants/routes";
+
+import PrivateGuard from "./private-guard";
+
+vi.mock("@/lib/stores/auth-store", () => ({
+  useAuthStore: vi.fn().mockReturnValueOnce({
+    authorized: false,
+    setAuthorized: vi.fn(),
+  }),
+}));
+
+vi.mock("@tanstack/react-query", () => ({
+  useQuery: vi.fn().mockReturnValueOnce({
+    isLoading: false,
+    isError: false,
+    isSuccess: false,
+  }),
+}));
+
+const routes: RouteObject[] = [
+  {
+    path: AppRoutes.SignIn,
+    element: <div>Sign In</div>,
+  },
+  {
+    element: <PrivateGuard />,
+    children: [
+      {
+        path: AppRoutes.Root,
+        element: <div>Root</div>,
+      },
+    ],
+  },
+];
+
+describe("Private Guard", () => {
+  it("redirects to sign-in page when not authorized", () => {
+    const router = createMemoryRouter(routes, {
+      initialEntries: [AppRoutes.Root],
+    });
+
+    render(<RouterProvider router={router} />);
+
+    expect(router.state.location.pathname).toEqual(AppRoutes.SignIn);
+  });
+
+  it("redirects to sign in page when an error occurs", () => {
+    const router = createMemoryRouter(routes, {
+      initialEntries: [AppRoutes.Root],
+    });
+
+    (useAuthStore as unknown as Mock).mockReturnValueOnce({
+      authenticated: true,
+      setAuthorized: vi.fn(),
+    });
+
+    (useQuery as Mock).mockReturnValueOnce({
+      isError: true,
+      isLoading: false,
+      isSuccess: false,
+    });
+
+    render(<RouterProvider router={router} />);
+
+    expect(router.state.location.pathname).toEqual(AppRoutes.SignIn);
+  });
+
+  it("allows access to root page when authorized", () => {
+    const router = createMemoryRouter(routes, {
+      initialEntries: [AppRoutes.Root],
+    });
+
+    (useAuthStore as unknown as Mock).mockReturnValueOnce({
+      authorized: true,
+      setAuthorized: vi.fn(),
+    });
+
+    (useQuery as Mock).mockReturnValueOnce({
+      isError: false,
+      isLoading: false,
+      isSuccess: true,
+    });
+
+    render(<RouterProvider router={router} />);
+
+    expect(router.state.location.pathname).toEqual(AppRoutes.Root);
+  });
+
+  it("renders loading component when query is loading", () => {
+    const router = createMemoryRouter(routes, {
+      initialEntries: [AppRoutes.Root],
+    });
+
+    (useAuthStore as unknown as Mock).mockReturnValueOnce({
+      authorized: true,
+      setAuthorized: vi.fn(),
+    });
+
+    (useQuery as Mock).mockReturnValueOnce({
+      isError: false,
+      isLoading: true,
+      isSuccess: false,
+    });
+
+    const { container } = render(<RouterProvider router={router} />);
+
+    const loader = container.querySelector("svg");
+
+    expect(loader).toBeInTheDocument();
+  });
+});