onchange

#!/usr/bin/env ruby

require('open3')

extra_fswatch_args, cmd_args = if (rest_index = ARGV.index('--'))
  [ARGV[0...rest_index], ARGV[rest_index+1..-1]]
else
  [[], ARGV]
end

if cmd_args.size == 1 && cmd_args =~ /[&;|]/
  cmd_args = ['bash', '-c', cmd_args[0]]
end

system(*cmd_args)

fswatch_args = [
  '-e', 'coverage',
  '-e', '/\.git',
  '--one-per-batch',
  *extra_fswatch_args,
  '.'
]

Open3.popen3('fswatch', *fswatch_args) do |stdin, stdout, stderr, wait_thr|
  stdin.close
  stdout.each { |_| system(*cmd_args) }
end