如何在catch语句之外的异步/等待中拒绝？

Question

As outlined by this SO post and answer , it is customary to throw an error from the catch statement that resides inside an async/await function like so:

} catch (error) {
    throw new Error(400);
}

As highlighted by that same post, you typically wouldn't return a rejected promise (see below) since it's a semantic mis-match with 'try-catch' statements.

} catch (error) {
    return Promise.reject(new Error(400));
}

By that same logic, should I be returning rejected promises when returning errors outside of catch statements from my async/await function instead of throwing them?

In other words is the following semantically inconsistent with the above logic?

async function promise () {
    throw new Error('Some error');
}

And, is this the preferred way of returning an error inside an async/await function since async/await functions implicitly return a promise?

async function promise () {
    return Promise.reject(new Error(400));
}

I'm aware both of the above snippets allow errors to be caught when consuming the promise.

Answer 1

You generally use throw where you can, ie in async function s or then callbacks, because it is simpler and therefore easier to read. return Promise.reject(…) does work but is lengthy.