Rspec: Drag and Drop file upload

intergration_spec_helper.rb

module IntegrationSpecHelper
  def drop_files files, drop_area_id
    js_script = "fileList = Array();"
    files.count.times do |i|
      # Generate a fake input selector
      page.execute_script("if ($('#seleniumUpload#{i}').length == 0) { seleniumUpload#{i} = window.$('<input/>').attr({id: 'seleniumUpload#{i}', type:'file'}).appendTo('body'); }")
      # Attach file to the fake input selector through Capybara
      attach_file("seleniumUpload#{i}", files[i])
      # Build up the fake js event
      js_script = "#{js_script} fileList.push(seleniumUpload#{i}.get(0).files[0]);"
    end

    # Trigger the fake drop event
    page.execute_script("#{js_script} e = $.Event('drop'); e.originalEvent = {dataTransfer : { files : fileList } }; $('##{drop_area_id}').trigger(e);")
  end
end

spec.rb

describe "when user drop files", js: true do
  before do
    files = [ Rails.root + 'spec/support/pdffile/pdfTest1.pdf',
              Rails.root + 'spec/support/pdffile/pdfTest2.pdf',
              Rails.root + 'spec/support/pdffile/pdfTest3.pdf' ]
    drop_files files, 'fileDropArea'
  end

  it "should ..." do
     should have_content '...'
  end
end