I have a small custom polyfill for Promise.all and while trying to execute it I see that update of array(errorList) in catch block is not working. Can someone please help me understand what am I missing.

Promise.customAll = function (promisesList) {
  let errorList = [];
  let resultList = [];
  return new Promise((resolve, reject) => {
    promisesList.forEach(async (promise, index) => {
      try {
        let result = await promise;
        resultList[index] = (result);
      } catch (err) {
        errorList.push(err);
      }
    });

    if (errorList.length) {
      reject(errorList);
    } else {
      resolve(resultList);
    }
  });
};

Here is how I am using it. For above code I am expecting my promise tp go to catch block but its going to then block and printing [ 'FirstPromise', <1 empty item>, '3rd Promise' ]

Promise.customAll([Promise.resolve("FirstPromise"), Promise.reject("Error in 2nd Promise"), Promise.resolve("3rd Promise")])
  .then((val) => {
    console.log(val);
  })
  .catch((err) => {
    console.log(err);
  });