class RuboCop::CacheConfig

@api private
This class represents the cache config of the caching RuboCop runs.

def self.root_dir

def self.root_dir
  root = ENV.fetch('RUBOCOP_CACHE_ROOT', nil)
  root ||= yield
  root ||= if ENV.key?('XDG_CACHE_HOME')
             # Include user ID in the path to make sure the user has write
             # access.
             File.join(ENV.fetch('XDG_CACHE_HOME'), Process.uid.to_s)
           else
             # On FreeBSD, the /home path is a symbolic link to /usr/home
             # and the $HOME environment variable returns the /home path.
             #
             # As $HOME is a built-in environment variable, FreeBSD users
             # always get a warning message.
             #
             # To avoid raising warn log messages on FreeBSD, we retrieve
             # the real path of the home folder.
             File.join(File.realpath(Dir.home), '.cache')
           end
  File.join(root, 'rubocop_cache')
end