class Utils::Finder

def build_paths
  paths = []
  visit = -> filename {
    s  = filename.stat
    bn = filename.pathname.basename
    if !s ||
        s.directory? && @config.discover.prune?(bn) ||
        s.file? && @config.discover.skip?(bn)
    then
      @args[?v] and warn "Pruning #{filename.inspect}."
      prune
    end
    true
  }
  find(*@roots, visit: visit) do |filename|
    filename.stat.directory? and filename << ?/
    paths << filename
  end
  paths.uniq!
  paths
end