Simple script to emulate Spin using TestR.

testr-spin

#!/usr/bin/env ruby
# This script emulates [Spin] using [TestR].
#
# Usage: testr-spin serve [-I<LOAD_PATH>]... <OVERHEAD_FILE>...
# Usage: testr-spin push <TEST_FILE> [<TEST_NAME>]...
#
# [Spin]: https://github.com/jstorimer/spin
# [TestR]: https://github.com/sunaku/testr

require 'json'

FIFO = File.basename(__FILE__) + '.fifo'

# Sends the given message to the Spin server.
def send message
  File.pipe? FIFO or fail 'Did you forget to run `testr-spin serve`?'
  File.open(FIFO, 'a') do |fifo|
    fifo.puts JSON.dump(message)
  end
end

case ARGV.shift
when 'serve'
  # create named pipe for Spin client to server communication
  system 'mkfifo', FIFO or fail 'Could not create named pipe.'

  if fork
    begin
      # continuously pass input from Spin client to server
      system "tail -f #{FIFO} | testr-master"
    ensure
      File.unlink FIFO
    end
  else
    # preload the Rails environment and the given Ruby files
    paths = %w[test spec]; files = Dir['{test,spec}/{test,spec}_helper.rb']
    ARGV.each {|a| a =~ /^-I/ ? paths.concat($'.split(/:+/)) : files << a }
    send [:load, paths, files]
  end

when 'push' then
  # tell the Spin server to load the given file and
  # only run the given tests within that given file
  send [:test, ARGV.shift, ARGV]

else
  # show usage information for this script
  puts File.read(__FILE__).split(/^$/).first
end