An auto runner script for Mac

Rakefile

task :default do
  puts 'hello world'
end

task :test do
  puts 'running test'
end

task :ancillary do
  puts 'ancillary'
end

sidekick.rb

# 1. Put this script next to your Rakefile.
# 2. Install the following gems:
#   - gem install rerun
#   - gem install readline
#   - gem install open3
# 3. Then run this script through ruby: ruby sidekick.rb

require 'readline'
require 'pty'
require 'open3'
require 'find'
require 'FileUtils'

def sidekick
  # THIS IS THE PARENT PROCESS FOR SIDEKICK YOU CAN USE THIS TO DO
  # DEV CENTRIC TASKS
  while expr = Readline.readline('', true)
    if expr == 'exit'
      exit(0)
    elsif expr == "custom"
      spawn_process "rake ancillary"
    else
      puts "I don't know what you want me to do with:"
      puts expr
    end
    sleep 0.2
  end
end

# Spawn a seperate process for rake.
def spawn_process command
  PTY.spawn("#{command}") do |stdout, stdin, _|
    @stdin = stdin
    Thread.new do
      loop do
        stdout.each { |line| print line }
        sleep 1
      end
    end
  end
end

# For this process trap SIGINT so it's not accidentally killed and orchestrates out of process interopability.
Signal.trap('INT') do
  puts ''
  puts '============================'
  puts 'SIGINT has to be disable because sometimes repl/rerun sends it here. Yes I agree this is silly.'
  puts "run `kill -9 #{Process.pid}` or press enter to exit."
  puts '============================'
end

# Process interop thats use by the file watcher called rerun.
@first_time = true

# 4. Set your default rake command here.
@rake_command = "rake test"

Signal.trap('SIGUSR1') do
  if @first_time
    @first_time = false
  else
    spawn_process @rake_command
  end
end

# And at the same time run the ruby file watcher
# File pattern to watch for to auto invoke rake.
@file_pattern = 'rb,c,h,mm,Rakefile'
PTY.spawn("rerun \"kill -30 #{Process.pid}\" --no-notify") do |stdout, _, _|
  Thread.new do
    loop do
      stdout.each { |line| print line if line !~ /\[rerun\]/ }
      sleep 1
    end
  end
end

spawn_process @rake_command
sidekick