Bluebird.prototype.map with native Promises

index.js

#!/usr/bin/env node
//@ts-check

const MAX_CONCURRENCY = 3;

function sayHiAsync() {
  console.log("marco");
  return new Promise((resolve) => {
    console.log("polo");
    setTimeout(() => {
      console.log("bravo");
      resolve("Hi!");
    }, 2000)
  })
}

async function concurrentPromises(inputs, promiseFactory, concurrency) {
  try {
    let results = [];
    while (inputs.length > 0) {
      const iterationInputs = inputs.splice(0, Math.min(inputs.length, concurrency));
      const iterationPromises = iterationInputs.map((input) => promiseFactory(input));
      console.log(`Evaluating: ${iterationPromises.length}. Evaluated: ${results.length}. Remaining: ${inputs.length}.`);
      const iterationResults = await Promise.all(iterationPromises);
      console.log(iterationResults);
      results = results.concat(iterationResults);
    }
    return results;
  } catch (error) {
    throw error;
  }
}

(async () => {
  const recipients = Array.from(new Array(10));
  let results = await concurrentPromises(recipients, sayHiAsync, MAX_CONCURRENCY);
  results.forEach((result) => console.log(result));
})();