Upload a file using Protractor -- From http://stackoverflow.com/questions/21305298/how-to-upload-file-in-angularjs-e2e-testing

upload.js

var util = require('util');

it('should upload file', function() {
  var fileToUpload = '../some/path/foo.txt';
  var absolutePath = path.resolve(__dirname, fileToUpload);
  $('input[type="file"]').sendKeys(absolutePath);

  $('#uploadButton').click();
});

what is __dirname ???