Promises are broken: https://twitter.com/isntitvacant/status/1042249543926992897

hahahahaha.js

function getValue(){
    return new Promise(function(resolve, reject){
        reject('fail');
    });
}

function doX(){
    var x = getValue();
    return new Promise(function(resolve, reject){
        setTimeout(function(){
            x.then(resolve).catch(reject);
        });
    });
}

doX().then(console.log).catch(console.log);

Oh yeah and this absolutely fails using async/await too:

function getValue(){
    return new Promise(function(resolve, reject){
        reject('fail');
    });
}

async function doX(){
    var x = getValue();
    var y = getValue();

    return await x + await y;
}

doX().then(console.log).catch(console.log);