May I ask why an async/await, await of es7 can sometimes be omitted?

Test Code: 


async function fun1(){
    return fun2();//  await await
}
async function fun2(){
    return fun3();//  await await
}

async function fun3(){
    return new Promise(resolve=>{
        console.log("fun3");
        resolve("fufff 3 ret");
    })
}

async function testfun1(){
    const ret = await fun1();
    console.log(ret);
}
testfun1()

the output of fun1 fun2 plus await is the same. 

fun3
fufff 3 ret

Why on earth is this?

Node.js javascript
Mar.13,2021
  1. first, awati should be followed by Promise instance.
  2. secondly, the async function returns an instance of Promise .

specific to the example of the landlord, fun1 , fun2 the previous async is redundant, because fun1 () = > fun2 () = > fun3 () has returned the Promise instance.

can be changed to the following code. 

function bar () {
    return new Promise((resolve, reject) => {
        setTimeout(() => {
            resolve('bar');
        }, 1000);
    });
}

async function foo () {
    let ret1 = bar();
    let ret2 = await bar();
    console.log(ret1); // Promise { 'bar' }
    console.log(ret2); // bar
}

foo();

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