Handling multiple function calls that each return a Promise using Promise.all

handlingMultipleFunctionCallsThatEachReturnAPromise.js

function asyncFunction(bool) {
  return new Promise((resolve, reject) => {
    setTimeout(() => {
      if(bool) {
        resolve('Promise resolved after 5 seconds');
      } else {
        reject('Promise rejected after 5 seconds');
      }
    }, 5000);   
  });
}

const unresolvedPromises = [];

for(let i = 0; i < 5; i++) {
  // push the function call to an array
  // gathering an array of unfinished/unresolved Promises
  unresolvedPromises.push(asyncFunction(true));
}

// Promise.all will wait for each unresolved function
// to finish before passing an array of results to the 
// .then
Promise.all(unresolvedPromises).then((result) => {
                                  console.log('Handle resolved results here', result);
                               })
                               .catch((err) => {
                                  // if a promise rejects, the resolved values will be lost 
                                  // and you will only receive one error in the .catch
                                  console.log('Handle rejected error here', err);
                               });