lib/AssetRef.js
function getFileMIME(file) {
  var idx = file.lastIndexOf('.')
  var ext = idx > -1 ? file.slice(idx) : null
  if (ext) ext = ext.toLowerCase().substring(1)
  return MIMES[ext] || MIMES.txt
}
function getFileMIME(file) {
  var idx = file.lastIndexOf('.')
  var ext = idx > -1 ? file.slice(idx) : null
  if (ext) ext = ext.toLowerCase().substring(1)
  return MIMES[ext] || MIMES.txt
}
function getFileMIME ( file ) { var idx = file . lastIndexOf ( '.' ) var ext = idx > - 1 ? file . slice ( idx ) : null if ( ext ) ext = ext . toLowerCase ( ) . substring ( 1 ) return MIMES [ ext ] || MIMES . txt }
get MIME by file name

@param  {String} file
@return {String}
get MIME by file name