数组去重切新数据覆盖旧数据

const dealRearrangement = (arr) => {
  var obj = {};
  arr = arr.reduce(function (item, next) {
    if (obj[next.id]) {
      item.map((i) => {
        if (i.id === next.id) {
          i.layerName = next.layerName;
          i.layerPercent = next.layerPercent;
        }
      });
    } else obj[next.id] = true && item.push(next);
    return item;
  }, []);
  return arr;
};
const arr = [
  {
    id: "1",
    layerName: "1",
    layerPercent: "1",
  },
  {
    id: "1",
    layerName: "2",
    layerPercent: "2",
  },
  {
    id: "1",
    layerName: "3",
    layerPercent: "3",
  },
  {
    id: "2",
    layerName: "4",
    layerPercent: "4",
  },
];
console.log(dealRearrangement(arr));