## written by David Lowenfels @ Internaut Design
## may be used/modified as long as credit is given

    def assert_emails_sent args = {}, &block
      opts = args.dup
      array_headers = [ :to, :from ]
      # if was pass a string as :to, or :from, then it implies an array with one member
      array_headers.each do |sym|
        opts[sym] = opts[sym].email if opts[sym].respond_to? :email  # convert to email if sent object with email attribute
        opts[sym] = []<<opts[sym] if opts[sym].is_a?( String ) # convert to array if given string
      end
      opts[:count] ||= 1
      
      ActionMailer::Base.deliveries.clear
      
      block.call
      deliveries = ActionMailer::Base.deliveries
      assert !deliveries.empty?, "No e-mail in delivery list"
      expected_deliveries = opts.delete(:count)
      assert_equal expected_deliveries, deliveries.size, "An unexpected number of emails were delivered"

      deliveries.each_with_index do |msg,idx|
        opts.each_pair do |k,v|
          val = msg.send( k )
          case v
          when Regexp
            error = "failure on deliveries[#{idx}].#{k}"
            if array_headers.include? k
              assert !val.grep( v ).empty?, error+" does not match #{v}"
            else
              assert_match v, val, error
            end
          else
            assert_equal v, val, error
          end
        end
      end
    end

    def assert_email_sent args = {}, &block
      assert_emails_sent args.merge(:count => 1), &block
      return ActionMailer::Base.deliveries.first
    end

    def assert_email_not_sent
      ActionMailer::Base.deliveries.clear
      yield
      assert ActionMailer::Base.deliveries.empty?, "Email was unexpectedly sent"
    end