check_examples

#!/usr/bin/env ruby

require 'fileutils'

args = ARGV.dup
if args.count < 2
  puts "Usage: ./check_examples.rb ./my_binary (n..m | n m k).  for example ./check_examples 1..4 will check examples 1 to 4 inclusive."
  exit(1);
end
cmd = args.shift 
print_only = false
sequence = args.map do |a| 
  case
    when a =~ /(\d+)\.\.(\d+)/
      (($1)..($2)).to_a
    when a =~ /^(-\d)$/
      puts "'-' is not yet implemented"
    when a == "-p"
      print_only = true
      nil
    else
      a
  end
end.flatten.compact

temp_file = "./tmp#{Time.now.to_i}.out"
sequence.each do |index|
  invoke_command = "#{cmd} < ./examples/#{index}.in > #{temp_file}"
  diff_command =  "diff ./examples/#{index}.out #{temp_file}"
  if print_only
    puts "#Example #{index}.out:"
    puts invoke_command
    puts diff_command
    puts
  else
    `#{invoke_command}`
    diff_output = `#{diff_command}`
    FileUtils.rm_f temp_file
    puts "Problem with example #{index}.out\n#{diff_output}\n" unless diff_output.empty?
  end
end