# class Gem::CommandManager

The command manager registers and installs all the individual sub-commands supported by the gem command.

Extra commands can be provided by writing a rubygems_plugin.rb file in an installed gem. You should register your command against the `Gem::CommandManager` instance, like this:

    # file rubygems_plugin.rb
    require 'rubygems/command_manager'

    Gem::CommandManager.instance.register_command :edit

You should put the implementation of your command in rubygems/commands.

    # file rubygems/commands/edit_command.rb
    class Gem::Commands::EditCommand < Gem::Command
      # ...
    end

See `Gem::Command` for instructions on writing gem commands.

### Constants

ALIAS_COMMANDS

### Public Class Methods

instance() click to toggle source

Return the authoritative instance of the command manager.

    # File lib/rubygems/command_manager.rb, line 86
    def self.instance
      @instance ||= new
    end

new() click to toggle source

Register all the subcommands supported by the gem command.

    # File lib/rubygems/command_manager.rb, line 108
    def initialize
      require_relative "timeout"
      @commands = {}

      BUILTIN_COMMANDS.each do |name|
        register_command name
      end
    end

reset() click to toggle source

Reset the authoritative instance of the command manager.

    # File lib/rubygems/command_manager.rb, line 101
    def self.reset
      @instance = nil
    end

### Public Instance Methods

[](command_name) click to toggle source

Returns a Command instance for `command_name`

    # File lib/rubygems/command_manager.rb, line 134
    def [](command_name)
      command_name = command_name.intern
      return nil if @commands[command_name].nil?
      @commands[command_name] ||= load_and_instantiate(command_name)
    end

command_names() click to toggle source

Return a sorted list of all command names as strings.

    # File lib/rubygems/command_manager.rb, line 143
    def command_names
      @commands.keys.collect(&:to_s).sort
    end

find_alias_command(cmd_name) click to toggle source

    # File lib/rubygems/command_manager.rb, line 212
    def find_alias_command(cmd_name)
      alias_name = ALIAS_COMMANDS[cmd_name]
      alias_name ? alias_name : cmd_name
    end

find_command(cmd_name) click to toggle source

    # File lib/rubygems/command_manager.rb, line 197
    def find_command(cmd_name)
      cmd_name = find_alias_command cmd_name

      possibilities = find_command_possibilities cmd_name

      if possibilities.size > 1
        raise Gem::CommandLineError,
              "Ambiguous command #{cmd_name} matches [#{possibilities.join(", ")}]"
      elsif possibilities.empty?
        raise Gem::UnknownCommandError.new(cmd_name)
      end

      self[possibilities.first]
    end

find_command_possibilities(cmd_name) click to toggle source

    # File lib/rubygems/command_manager.rb, line 217
    def find_command_possibilities(cmd_name)
      len = cmd_name.length

      found = command_names.select {|name| cmd_name == name[0, len] }

      exact = found.find {|name| name == cmd_name }

      exact ? [exact] : found
    end

instance() click to toggle source

Returns self. Allows a `CommandManager` instance to stand in for the class itself.

    # File lib/rubygems/command_manager.rb, line 94
    def instance
      self
    end

process_args(args, build_args=nil) click to toggle source

    # File lib/rubygems/command_manager.rb, line 167
    def process_args(args, build_args=nil)
      if args.empty?
        say Gem::Command::HELP
        terminate_interaction 1
      end

      case args.first
      when "-h", "--help" then
        say Gem::Command::HELP
        terminate_interaction 0
      when "-v", "--version" then
        say Gem::VERSION
        terminate_interaction 0
      when "-C" then
        args.shift
        start_point = args.shift
        if Dir.exist?(start_point)
          Dir.chdir(start_point) { invoke_command(args, build_args) }
        else
          alert_error clean_text("#{start_point} isn't a directory.")
          terminate_interaction 1
        end
      when /^-/ then
        alert_error clean_text("Invalid option: #{args.first}. See 'gem --help'.")
        terminate_interaction 1
      else
        invoke_command(args, build_args)
      end
    end

register_command(command, obj=false) click to toggle source

Register the `Symbol` `command` as a gem command.

    # File lib/rubygems/command_manager.rb, line 120
    def register_command(command, obj=false)
      @commands[command] = obj
    end

run(args, build_args=nil) click to toggle source

Run the command specified by `args`.

    # File lib/rubygems/command_manager.rb, line 150
    def run(args, build_args=nil)
      process_args(args, build_args)
    rescue StandardError, Gem::Timeout::Error => ex
      if ex.respond_to?(:detailed_message)
        msg = ex.detailed_message(highlight: false).sub(/\A(.*?)(?: \(.+?\))/) { $1 }
      else
        msg = ex.message
      end
      alert_error clean_text("While executing gem ... (#{ex.class})\n    #{msg}")
      ui.backtrace ex

      terminate_interaction(1)
    rescue Interrupt
      alert_error clean_text("Interrupted")
      terminate_interaction(1)
    end

unregister_command(command) click to toggle source

Unregister the `Symbol` `command` as a gem command.

    # File lib/rubygems/command_manager.rb, line 127
    def unregister_command(command)
      @commands.delete command
    end

### Private Instance Methods

invoke_command(args, build_args) click to toggle source

    # File lib/rubygems/command_manager.rb, line 249
    def invoke_command(args, build_args)
      cmd_name = args.shift.downcase
      cmd = find_command cmd_name
      terminate_interaction 1 unless cmd
      cmd.deprecation_warning if cmd.deprecated?
      cmd.invoke_with_build_args args, build_args
    end

load_and_instantiate(command_name) click to toggle source

    # File lib/rubygems/command_manager.rb, line 229
    def load_and_instantiate(command_name)
      command_name = command_name.to_s
      const_name = command_name.capitalize.gsub(/_(.)/) { $1.upcase } << "Command"
      load_error = nil

      begin
        begin
          require "rubygems/commands/#{command_name}_command"
        rescue LoadError => e
          load_error = e
        end
        Gem::Commands.const_get(const_name).new
      rescue StandardError => e
        e = load_error if load_error

        alert_error clean_text("Loading command: #{command_name} (#{e.class})\n\t#{e}")
        ui.backtrace e
      end
    end