let list = [{
        id: 1
    }, {
        id: 1
    }, {
        id: 2
    }]
    let arr = Object.values(list.reduce((res, item) => {
        res[item.id] ? res[item.id].push(item) : res[item.id] = [item];
        return res;
    }, {}));
    console.log(arr)