Failed models for a prompt test

prompt_test.rb

      def prompt_test(cmd, script, prompt)
        cmd, leader = cmd.lstrip.split(/^/, 2)
        
        inputs = []
        expected = [leader]
        script.lstrip.split(/^#{prompt}/).each do |lines|
          next if lines.empty?

          input, output = lines.split(/^/, 2)
          inputs   << input
          expected << output
        end
        
        IO.popen(cmd, "r+") do |io|
          io.write inputs.join
          io.close_write
          assert_equal expected.join, io.read
        end
      end
      
      def prompt_test(cmd, script, prompt)
        cmd, leader = cmd.lstrip.split(/^/, 2)
        
        prompt_regexp = /^#{prompt}/
        Open3.popen3(cmd) do |i, o, s|
          if leader
            assert_equal leader, o.read_nonblock(leader.length)
          end
          
          n = 0
          script.lstrip.split(prompt_regexp).each do |lines|
            n += 1
            next if lines.empty?

            input, expected = lines.split(/^/, 2)
            i.write(input)
            assert_equal expected, o.read(expected.length), "at input #{n}: #{prompt}#{input}"
            assert_equal prompt, o.read(prompt.length), "after input: #{n} (incorrect prompt)"
          end
        end
      end

  def test_irb_prompt_test
        prompt_test "irb", %Q{
>> 1 + 2
=> 3
>> puts "goodnight moon"
goodnight moon
=> nil
>> exit
}, ">> "
  end
  
  def test_python_prompt_test
    prompt_test "python", %Q{
>>> 1 + 2
3
>>> exit()
}, ">>> "

  end