mailtrap.rb

# Put this in features/env/mailtrap.rb to automatically run mailtrap for your Cucumber tests.

class Mailtrap
  def self.start
    @mailtrap_file = File.expand_path(File.join(File.dirname(__FILE__), '..', '..', 'tmp', 'mailtrap.log'))
    clear_mailtrap_file
    @mailtrap = IO.popen("mailtrap run --file=#{@mailtrap_file}")
  end

  def self.clear_mailtrap_file
    FileUtils.rm_f @mailtrap_file
  end

  def self.stop
    Process.kill('HUP', @mailtrap.pid)
  end

  def self.content
    File.read(@mailtrap_file)
  end
end

Mailtrap.start

at_exit do
  Mailtrap.stop
end

After do |scenario|
  unless scenario.failed?
    Mailtrap.clear_mailtrap_file
  end
end