class Gem::Commands::EnvironmentCommand

def execute
  out = String.new
  arg = options[:args][0]
  out <<
    case arg
    when /^version/ then
      Gem::VERSION
    when /^gemdir/, /^gemhome/, /^home/, /^GEM_HOME/ then
      Gem.dir
    when /^gempath/, /^path/, /^GEM_PATH/ then
      Gem.path.join(File::PATH_SEPARATOR)
    when /^user_gemdir/, /^user_gemhome/ then
      Gem.user_dir
    when /^remotesources/ then
      Gem.sources.to_a.join("\n")
    when /^platform/ then
      Gem.platforms.join(File::PATH_SEPARATOR)
    when /^credentials/, /^creds/ then
      Gem.configuration.credentials_path
    when nil then
      show_environment
    else
      raise Gem::CommandLineError, "Unknown environment option [#{arg}]"
    end
  say out
  true
end