普通耗时函数写成promise写法

异步函数转换成promise写法

function getArrayData (pathFile) {
  return new Promise(function (result) {
    const fileStream = fs.createReadStream(pathFile);
    const allDatas = [];
    csv
    .fromStream(fileStream, {
      headers: true
    })
    .on('data', (data) => {
      allDatas.push(data);
    })
    .on('end', async () => {
      result(allDatas);
    });
  });
}