Test controller with file upload

gistfile1.rb

describe "POST to #create" do
  # Will use the file located at rspec/fixtures/files/test-document.pdf
  let(:attachement) { fixture_file_upload('/files/test-document.pdf', "text/pdf") }

  before do
      post :create, attachment: {title: "Attachment Title", attachment: file_attachment}
  end
  it {should redirect_to some_path }
end