Hello,I want to create the .tar,but after creation inside of the tar is empty.Soemone knows why?Thanks in advance

Here is my code.What should I add here?

  grunt.registerTask('speak',function(){
    var tar = require('tar-fs');
    var fs = require('fs');

    //packing a directory 
    tar.pack('C:/Users/user/Desktop/yoo').pipe(fs.createWriteStream('my-test3.tar'));

});

via John