Example code demonstrating the not immediately apparent issue of a promise rejecting while another one is being awaited.

async_await_trap.js

async function main() {
    const rej = Promise.reject('err')
    // the following line is needed,
    // otherwise UnhandledPromiseRejectionWarning is thrown
    // which can't be caught anywhere else (not even by async caller)!
    // can be NOOP though, if error handling may be delayed to below catch block
    rej.catch(e => console.log(e)) // logs 'err'

    const del = new Promise((resolve) => {
        setTimeout(() => resolve('del'), 100)
    })

    try {
        await del
    } catch (e) {
        console.log(e)
    }

    try {
        await rej
    } catch (e) {
        console.log(e) // logs 'err'
    }

    console.log('fin') // logs 'fin'
}

/**
 * OUTPUT:
 * err
 * err
 * fin
 */
main()