brew_cask_upgrade.rb

# Location of casks
CASKROOM = '/opt/homebrew-cask/Caskroom/'
TAPS = '/usr/local/Library/Taps/caskroom/'

MIN_AGE = 30 # days

require 'date'
require 'simple_progressbar'

i=1
SimpleProgressbar.new.show('Updating') do

  Dir.foreach(CASKROOM) do |cask_name|

    i = i+1
    progress 100 * i / Dir.entries(CASKROOM).length

    # Ignore hidden files/directories ('..' and '.' too)
    next if cask_name.chr == '.'

    # Get the info for the cask and find the newest version.
    cask_location = File.join(CASKROOM, cask_name)

    # Get the list of installed versions from cask directory
    cask_dir_contents = %x(ls #{cask_location}).split.map(&:strip)
    installed_versions = cask_dir_contents
    installed_versions.reject! { |file_or_dir| file_or_dir.chr == '.' }

    cask_formula_location = nil
    Dir.foreach(TAPS) do |cask_repo|
      next if cask_repo.chr == '.'
      cask_formula_location_maybe = File.join(TAPS, cask_repo, 'Casks', cask_name + '.rb')
      cask_formula_location = cask_formula_location_maybe if File.exists?(cask_formula_location_maybe)
    end

    print "\r", cask_name, " is DELETED from repository! \n" unless cask_formula_location
    next unless cask_formula_location

    uses_pkg = system('grep', '^[[:space:]]*pkg[[:space:]]', cask_formula_location, :out => '/dev/null')
    # uses_app = system('grep', '^[[:space:]]*app[[:space:]]', cask_formula_location, :out => '/dev/null')
    uses_font= system('grep', '^[[:space:]]*font[[:space:]]', cask_formula_location, :out => '/dev/null')
    # uses_ql = system('grep', '^[[:space:]]*qlplugin[[:space:]]', cask_formula_location, :out => '/dev/null')

    if installed_versions.include?('latest')

      age = (Date.today - File.mtime(cask_location).to_date).round

      next if age < MIN_AGE
      # Fonts are updated way less often, so they use 4×MIN_AGE
      next if uses_font and age < MIN_AGE * 4

      print "\r", cask_name, ' — ', age, 'd ago'

    else

      # Find the newest version.
      newest_version = %x(brew cask info #{cask_name}).lines.first.split.map(&:strip).last
      #BAD:
      #      newest_version = open(cask_formula_location).each_line.find { |line| line.split.first == 'version' }.split.last.gsub(/[\'\"\`]/, '')

      next if installed_versions.include?(newest_version)

      print "\r", cask_name, ' ', installed_versions.join(", "), ' -> ', newest_version

#      print "\n" ; next

    end

    if installed_versions.include?('latest')
      if uses_pkg
        print ", uses .pkg"
        # next
      end

      # unless uses_app || uses_font || uses_ql
        # print ', is tricky: ', cask_formula_location, "\n"
        # next
      # end
    end

    print ' … ', 'uninstalling ', installed_versions.join(", "), ":\n"
    unless system('brew cask uninstall --force ' + cask_name)
      $stderr.puts "Oops, I've tried to remove #{cask_name} #{installed_versions} and cask gone haywire. I'm sorry!"
      $stderr.puts " Offending cask: #{cask_formula_location}"
      $stderr.puts " Failed install command: brew cask uninstall --force #{cask_name}"
      exit 1
    end

    print 'installing ', newest_version, ":\n"
    unless system('brew cask install ' + cask_name)
      $stderr.puts "Oops, I've removed #{cask_name} #{installed_versions} and couldn't reinstall it. I'm sorry!"
      $stderr.puts " Offending cask: #{cask_formula_location}"
      $stderr.puts " Failed install command: brew cask install #{cask_name}"
      exit 1
    end
    puts

  end
end