text: import {
    ADD_COUNTER,
    ADD_TO_CART
  } from './mutations_type'
  export default {
    addCart(context,payload){
      return new Promise((resolve,reject) => {
        /*let oldProduct = null;
      // 新添加的商品，判断是否已经存在该商品，比较id值
      for(let item of state.cartList){
        if(item.id === payload.id){
          oldProduct = item;
        }
      }*/
  
        let oldProduct = context.state.cartList.find( item => {
          return item.id === payload.id
        })
  
        // 2、判断oldProduct
        if(oldProduct){
          context.commit(ADD_COUNTER,oldProduct)
          resolve('当前的商品数量+1')
        }else{
          payload.count = 1;
          context.commit(ADD_TO_CART,payload)
          resolve('添加新的商品')
        }
      })
    }
  };
  