Await used after promise initialized

Yes, if you use await with an async function then the code will block until the promise has either resolved or failed. You should wrap your await block in a try catch to handle any errors.

async function test() {
    let task = asyncTask()
    //function still running
    try {
        await task
        //code executed only if task is resolved
    } catch (err){
        //Something went wrong
        throw new Error(err);
    }
}

Using async/await has the same functionality as a promise, but just provides a more synchronous way of writing your code.

If you wanted to rewrite the code as a promise then it would look like:

function test() {
    myPromise('some arguments')
    .then(result => console.log(`Task completed: ${result}`);)
    .catch(err => console.error(err));
}

async/await

async:The word async before a function means one simple thing: a function always returns a promise.

await:The keyword await makes JavaScript wait until that promise settles and returns its result.

Here

  async function test() {
    let task = asyncTask() //return a promise
    //function still running
    await task
    //code executed only if task is resolved
}  

The function execution “pauses” at the line (await task) and resumes when the promise settles, with task becoming its result.

Let’s emphasize: await literally makes JavaScript wait until the promise settles, and then go on with the result.

If a promise resolves normally, then await promise returns the result. But in case of a rejection it throws the error .

1. Either as already said in answer We should catch that error using try..catch

async function test() {
    let task = asyncTask()
    //function still running
    try {
        await task
   } catch (err){
       throw new Error(err);
    }
}

2. If we don’t have try..catch, then the promise generated by the call of the async function test() becomes rejected. We can append .catch to handle it:

async function test() {
        let task = asyncTask() //return a promise
        //function still running
        await task
        //code executed only if task is resolved
    } 
 test().catch(//error);

More If .catch is not there, then we get an unhandled promise error. We can catch such errors using a global event handler.