将两个数组对比后合并为同一个数组

let arr = [{week:"1"},
{week:"2"},
{week:"3"},
{week:"4"},
{week:"5"},
{week:"6"},
{week:"7"},
{week:"8"},
{week:"9"},
{week:"10"},
{week:"11"},
{week:"12"},
{week:"13"}]

let bb = [
    {week:"2",tongbi:"234"},
    {week:"5",tongbi:"54"}];

const composeData = (target,source) => {
    return target.map(item => {
        const findItem = source.find(el => el.week === item.week);//识别week值是否相等，如相等，findItem等于当前el
　　　　　return findItem || Object.assign(item,{tongbi:'0'}) 

　　}) 
} 
console.log(composeData(arr,bb))

// 目标

// [{week:"1",tongbi:"0"},

// {week:"2",tongbi:"234"},

// {week:"3",tongbi:"0"},

// {week:"4",tongbi:"0"},

// {week:"5",tongbi:"54"},

// {week:"6",tongbi:"0"},

// {week:"7",tongbi:"0"},

// {week:"8",tongbi:"0"},

// {week:"9",tongbi:"0"},

// {week:"10",tongbi:"0"},

// {week:"11",tongbi:"0"},

// {week:"12",tongbi:"0"},

// {week:"13",tongbi:"0"}]