wait-for-input.js

export const getInput = () => new Promise((resolve, reject) => {
    document.querySelector('form').addEventListener('submit', function listener(e) {
        e.preventDefault()
        const inputString = e.target.querySelector('input[type=text]').value
        resolve(inputString)
        e.target.removeEventListener('submit', listener)
    })
})

/* USAGE
const credentials = await getInput()
const [ username, password ] = credentials.split('|').map(s => s.trim())
console.log(credentials)
*/