react学习过程中遇到的错误记录

import React, { Component } from ‘react‘;
import Test from ‘./components/Test.jsx‘;
import ‘./assets/css/todolist.css‘;

class App extends Component {
  //组件的构造函数,当这个组件被执行的时候，constructor会自动被执行
  constructor(props){
    //固定的写法
    super(props);
    this.state = {
      list: [
        ‘learn react‘,
        ‘learn english‘,
        ‘learn vue‘
      ]
    }
  }

  handleBtnClick() {
    this.state.list.push(‘hello world‘);
  }

  render() {
    return (
      <div>
        <div>
          <Test/>
        </div>

        <div className="todoListStyle">
          <div>
          <input />
          <button onClick={this.handleBtnClick}>Add</button>
          </div>
          <ul>
            {
              this.state.list.map((item) => {
                return <li>{item}</li>
              })
            }
          </ul>
        </div>
      </div>
    );
  }
}

export default App;