remove_old_brews.rb

require 'fileutils'

LINKED_KEGS_PATH = '/usr/local/Library/LinkedKegs'

class Keg
  def initialize(linked_path)
    @linked_path = linked_path
    if linked_path.start_with? '.'
      @linked_path = File.join(LINKED_KEGS_PATH, linked_path)
    end

    @linked_path = File.absolute_path @linked_path
  end

  def old_version_paths
    paths = Array.new
    Dir.foreach(File.dirname @linked_path) {|x|
      if x != '.' and x != '..'
        full_path = File.join(File.dirname(@linked_path), x)
        paths << full_path if full_path != @linked_path
      end
    }

    paths
  end
end

kegs = Array.new
Dir.foreach(LINKED_KEGS_PATH) {|x|
  full_path = File.join(LINKED_KEGS_PATH, x)
  if File.symlink? full_path
    kegs.push Keg.new(File.readlink(full_path))
  end
}

kegs.each {|k|
  k.old_version_paths.each {|p|
    puts "removing #{p}..."
    FileUtils.rm_rf p
  }
}