问为什么执行不停止等待(异步/等待JS)？

EN

async function runPromises(promises, limit) {
  const LIMIT = limit || 10;
  let promsCopy = promises.slice();
  let counter = 0;
  let queue = [];
  while (promsCopy.length !== 0) {
    if (counter < LIMIT) {
      let prom = promsCopy.shift();
      if (prom) {
        queue.push(prom());
        counter += 1;
        if (counter >= LIMIT) {
          let [completed] = await Promise.race(
            queue.map((p) => p.then((_) => [p]))
          );
          queue.splice(queue.indexOf(completed), 1);
          counter -= 1;
        }
      }
    }
  }
  await Promise.all(queue);
}

// the code below is just for testing

const asyncFuncLong = () => {
  return new Promise((resolve, reject) => {
    setTimeout(() => {
      resolve();
    }, 6000);
  });
};

const asyncFuncShort = () => {
  return new Promise((resolve, reject) => {
    setTimeout(() => {
      resolve();
    }, 1000);
  });
};

let fns = [
  asyncFuncLong,
  asyncFuncLong,
  asyncFuncLong,
  asyncFuncLong,
  asyncFuncLong,
  asyncFuncLong,
  asyncFuncLong,
  asyncFuncLong,
  asyncFuncLong,
  asyncFuncLong,
  asyncFuncLong,
  asyncFuncLong,
  asyncFuncLong,
  asyncFuncLong,
  asyncFuncLong,
  asyncFuncLong,
];

let start = Date.now();

runPromises(fns, 10).then(() => {
  console.log(Date.now() - start);
});