javascript - 获取/承诺函数未正确返回

Question

我使用 2 个库（heic2any 和图像转换）来尝试将 heic 图像转换和压缩为 jpeg。目前，我无法获得按正确顺序返回的承诺

e = screenInput(e);

async function screenInput(filename) {
  //checks file extension
  var ext = getExtension(filename);
  switch (ext.toLowerCase()) {
    case 'jpg':
    case 'jpeg':
    case 'png':
    case 'bmp':
      return(compressim(filename));
      break;
    case 'heic':
      var url = URL.createObjectURL(filename)
      var result = await heicConvert(url)
      return compressOnly(result);
      break;
    default:
      return filename
      break;
  }
}


 function heicConvert(input) {
   return fetch(input)
    .then((res)=>res.blob())
    .then((blob)=>(heic2any({blob,toType:"image/jpeg"})))
  }

  function compressOnly(image) {
  var file
  file = new File([imageConversion.compressAccurately(image,500)], image.name, {type: "image/jpeg"})
  return file
}

目前它返回一个未决的承诺

var result = await heicConvert(url)

甚至在开始 compressOnly(result);

任何帮助将不胜感激，已经坚持了一段时间！