React-Redux失败的propType -值未定义

// 父组件
<ChildComponent someProp={value} />

// 子组件
ChildComponent.defaultProps = {
  someProp: defaultValue
};

function ParentComponent({ data }) {
  if (!data) return null;
  return <ChildComponent someProp={data} />;
}

import { connect } from 'react-redux';
import { someAction } from './actions';

const mapStateToProps = state => ({
  someProp: state.someReducer.someValue
});

const mapDispatchToProps = {
  someAction
};

export default connect(mapStateToProps, mapDispatchToProps)(ChildComponent);

// UserDetails.js
import PropTypes from 'prop-types';

function UserDetails({ user }) {
  return (
    <div>
      <h1>{user.name}</h1>
      <p>{user.email}</p>
    </div>
  );
}

UserDetails.propTypes = {
  user: PropTypes.shape({
    name: PropTypes.string.isRequired,
    email: PropTypes.string.isRequired
  }).isRequired
};

UserDetails.defaultProps = {
  user: {
    name: 'Guest',
    email: 'guest@example.com'
  }
};

export default UserDetails;

// App.js
import React, { useEffect, useState } from 'react';
import UserDetails from './UserDetails';

function App() {
  const [user, setUser] = useState(null);

  useEffect(() => {
    // 假设这是一个异步获取用户数据的函数
    fetchUser().then(data => setUser(data));
  }, []);

  return (
    <div>
      {user ? <UserDetails user={user} /> : <p>Loading...</p>}
    </div>
  );
}

export default App;