关于javascript:JS-数组转为树形结构根据id分梯次排序

要害代码：

let data = [{id: 1, pid: 0, name: 'body'}, 
            {id: 2, pid: 1, name: 'title'}, 
            {id: 3, pid: 1, name: 'div'}, 
            {id: 4, pid: 3, name: 'span'}, 
            {id: 5, pid: 3, name: 'icon'}, 
            {id: 6, pid: 4, name: 'subspan'}]

function toTree(data) {let result = []
    if(!Array.isArray(data)) {return result}
    data.forEach(item => {delete item.children;});
    let map = {};
    data.forEach(item => {map[item.id] = item;
    });
    data.forEach(item => {let parent = map[item.pid];
        if(parent) {(parent.children || (parent.children = [])).push(item);
        } else {result.push(item);
        }
    });
    return result;
}

let array = toTree(data);