diff --git a/frontend/tests/unit/RedirectIfAuthed.test.tsx b/frontend/tests/unit/RedirectIfAuthed.test.tsx
index f1debfc..2ce6ffa 100644
--- a/frontend/tests/unit/RedirectIfAuthed.test.tsx
+++ b/frontend/tests/unit/RedirectIfAuthed.test.tsx
@@ -2,7 +2,7 @@
 import { describe, it, expect } from 'vitest';
 import { screen } from '@testing-library/react';
 import { Routes, Route } from 'react-router-dom';
-import { renderShell } from './renderShell';
+import { renderShell, type RenderShellOptions } from './renderShell';
 import RedirectIfAuthed from '../../src/router/RedirectIfAuthed';
 
 function LoginScreen() {
@@ -17,7 +17,7 @@ function UsersSentinel() {
 
 function renderTree(
   initialEntries: { pathname: string; state?: unknown }[] | string[],
-  preloadedAuth?: Parameters<typeof renderShell>[1]['preloadedAuth'],
+  preloadedAuth?: RenderShellOptions['preloadedAuth'],
 ) {
   return renderShell(
     <Routes>
diff --git a/frontend/tests/unit/RequireAuth.test.tsx b/frontend/tests/unit/RequireAuth.test.tsx
index e770c5d..4a5945f 100644
--- a/frontend/tests/unit/RequireAuth.test.tsx
+++ b/frontend/tests/unit/RequireAuth.test.tsx
@@ -1,8 +1,8 @@
 // REQ-USR-004: RequireAuth 守卫三态（BR1） — authResolving / unauthenticated / ready
 import { describe, it, expect } from 'vitest';
 import { screen } from '@testing-library/react';
-import { Routes, Route, Outlet, useLocation } from 'react-router-dom';
-import { renderShell } from './renderShell';
+import { Routes, Route, useLocation } from 'react-router-dom';
+import { renderShell, type RenderShellOptions } from './renderShell';
 import RequireAuth from '../../src/router/RequireAuth';
 
 // 哨兵：登录页读出 state.from，便于断言重定向携带来源
@@ -16,7 +16,7 @@ function ProtectedSentinel() {
   return <div data-testid="protected-sentinel">protected-content</div>;
 }
 
-function renderGuard(initialEntries: string[], preloadedAuth?: Parameters<typeof renderShell>[1]['preloadedAuth']) {
+function renderGuard(initialEntries: string[], preloadedAuth?: RenderShellOptions['preloadedAuth']) {
   return renderShell(
     <Routes>
       <Route path="/login" element={<LoginSentinel />} />
diff --git a/frontend/tests/unit/router.test.tsx b/frontend/tests/unit/router.test.tsx
index f509540..b6a0a0a 100644
--- a/frontend/tests/unit/router.test.tsx
+++ b/frontend/tests/unit/router.test.tsx
@@ -1,13 +1,13 @@
 // REQ-USR-003: 路由表接线（替换 / 占位，含守卫与重定向，BR1/BR2/D7）
 import { describe, it, expect } from 'vitest';
 import { screen } from '@testing-library/react';
-import { renderShell } from './renderShell';
+import { renderShell, type RenderShellOptions } from './renderShell';
 import AppRouter from '../../src/router';
 import type { AuthUser } from '../../src/api/types';
 
 const ADMIN: AuthUser = { id: 1, sUserName: '朱子纯', sUserType: '超级管理员', sLanguage: '中文' };
 
-function renderRouter(initialEntries: string[], preloadedAuth?: Parameters<typeof renderShell>[1]['preloadedAuth']) {
+function renderRouter(initialEntries: string[], preloadedAuth?: RenderShellOptions['preloadedAuth']) {
   return renderShell(<AppRouter />, { initialEntries, preloadedAuth });
 }