const lp = require('long-promise2');

lp.enable();

// Simulate some stuff
const stuff = x => 2 + x;

// Simulate a delay.
const delay = ms => x => {
    // This function is `buggy` and will throw if the delay is 100ms.
    if (ms === 100) throw new Error('boom');

    return new Promise(res => {
        setTimeout(() => {
            res(x);
        }, ms);
    });
};

const nestedProblems = x => () => {
    // After the third call, go to an eventual `delay(100)` that throws
    if (x === 3) return Promise.resolve(1).then(delay(100));

    // Promise chain with recursion
    return Promise.resolve(1)
        .then(delay(10))
        .then(stuff)
        .then(nestedProblems(x + 1));
};

// Main program
function run() {
    const p = Promise.resolve(2);

    // Do some things. Something along this promise chain will throw.
    p.then(stuff)
        .then(delay(10))
        .then(stuff)
        .then(delay(10))
        .then(stuff)
        .then(nestedProblems(1))
        .then(stuff)
        .then(stuff)
        .catch(err => {
            console.log(lp.getLongStack(err));
            // Profit
        });
}

run();