问在使用svelte/store update方法更新对象时，是否应该使用spread操作符？

EN

//stores.js

import { writable } from "svelte/store";

export const counts = writable({ n: 0 });

//App.js

<script>
  import { count } from "./stores.js";

  function withSpreadOperator() {
    count.update(o => {
      let x = { ...o };
      x.n++;
      return x;
    });
  }

  function withoutSpreadOperator() {
    count.update(o => {
      o.n++;
      return o;
    });
  }
</script>

<h1>The count is {$count.n}</h1>
<button on:click="{withSpreadOperator}">+</button>
<button on:click="{withoutSpreadOperator}">+</button>