email_steps.rb

Then /^"([^"]*)" I should receive an email$/ do |recipient|
  @email = ActionMailer::Base.deliveries.detect do |m|
    m.to.include? recipient
  end
  assert @email
end

Then /^that email should have a (\w+) attachment$/ do |type|
  assert @email.attachments.detect { |a| a.mime_type.match(type) }
end