问如何在输入值上自动增长文本？

EN

// select DOM elements
const todoForm = document.querySelector(".todo-form");
const addButton = document.querySelector(".add-button");
const input = document.querySelector(".todo-input");
const ul = document.getElementById("todoList");

let todos = [];

todoForm.addEventListener("submit", function (e) {
  e.preventDefault();
  addTodo(input.value);
});

const addTodo = (input) => {
  if (input !== "") {
    const todo = {
      id: Date.now(),
      name: input,
      completed: false
    };
    todos.push(todo);
    renderTodos();
    todoForm.reset();
  }
};

const renderTodos = (todo) => {
  ul.innerHTML = "";
  todos.forEach((item) => {
    let li = document.createElement("LI");
    // li.classList.add('item');
    li.setAttribute("class", "item");
    li.setAttribute("data-key", item.id);
    const itemText = createTodoText(item);
    const cb = buildCheckbox(item);
    const db = buildDeleteButton(item);
    // if (item.completed === true) {
    //  li.classList.add('checked');
    // }
    li.append(cb);
    li.append(db);
    li.append(itemText);

    ul.append(li);
  });
};

const createTodoText = (todo) => {
  const itemText = document.createElement("span");
  itemText.setAttribute('role','textbox');
  itemText.setAttribute('contenteditable',"true");
  itemText.classList.add("todoText");
  itemText.innerHTML = todo.name;
  itemText.addEventListener("click", (e) => {
    e.currentTarget.classList.add("active");
  });
  // update todo item when user clicks away
  itemText.addEventListener("blur", (e) => {
    todo.name = e.target.textContent;
    renderTodos();
  });
  return itemText;
};

const buildCheckbox = (todo) => {
    const cb = document.createElement('input');
    cb.type = 'checkbox';
    cb.name = 'checkbox';
    cb.classList.add('checkbox');
    cb.checked = todo.completed;
    // checkbox not staying on current state ??
    cb.addEventListener('click', function (e) {
        if (e.target.type === 'checkbox') {
            // todo.completed = e.target.value;
      todo.completed = e.currentTarget.checked
            e.target.parentElement.classList.toggle('checked');
        } 
    });
    return cb;
};

const buildDeleteButton = (todo) => {
  const deleteButton = document.createElement("button");
  deleteButton.className = "delete-button";
  deleteButton.innerText = "x";
  deleteButton.addEventListener("click", function (e) {
    // duplicates children sometimes ??
    const div = this.parentElement;
    div.style.display = "none";
    todos = todos.filter((item) => item.id !== todo.id);
  });
  return deleteButton;
};

// //------ Local Storage ------
function addToLocalStorage(todos) {}

function getFromLocalStorage() {}

// getFromLocalStorage();