class Gem::Commands::UpdateCommand

def which_to_update(highest_installed_gems, gem_names)
  result = []
  highest_installed_gems.each do |_l_name, l_spec|
    next if !gem_names.empty? &&
            gem_names.none? {|name| name == l_spec.name }
    highest_remote_tup = highest_remote_name_tuple l_spec
    next unless highest_remote_tup
    result << highest_remote_tup
  end
  result
end