class Gem::CommandManager - RDoc Documentation

# 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.

### Public Class Methods

instance() click to toggle source

Return the authoritative instance of the command manager.

    # File lib/rubygems/command_manager.rb, line 75
    def self.instance
      @command_manager ||= new
    end

new() click to toggle source

Register all the subcommands supported by the gem command.

    # File lib/rubygems/command_manager.rb, line 97
    def initialize
      require '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 90
    def self.reset
      @command_manager = 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 123
    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 132
    def command_names
      @commands.keys.collect {|key| key.to_s}.sort
    end

find_command(cmd_name) click to toggle source

    # File lib/rubygems/command_manager.rb, line 174
    def find_command(cmd_name)
      possibilities = find_command_possibilities cmd_name

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

      self[possibilities.first]
    end

find_command_possibilities(cmd_name) click to toggle source

    # File lib/rubygems/command_manager.rb, line 187
    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 83
    def instance
      self
    end

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

    # File lib/rubygems/command_manager.rb, line 151
    def process_args(args, build_args=nil)
      if args.empty? then
        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 /^-/ then
        alert_error "Invalid option: #{args.first}. See 'gem --help'."
        terminate_interaction 1
      else
        cmd_name = args.shift.downcase
        cmd = find_command cmd_name
        cmd.invoke_with_build_args 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 109
    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 139
    def run(args, build_args=nil)
      process_args(args, build_args)
    rescue StandardError, Timeout::Error => ex
      alert_error "While executing gem ... (#{ex.class})\n    #{ex}"
      ui.backtrace ex

      terminate_interaction(1)
    rescue Interrupt
      alert_error "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 116
    def unregister_command(command)
      @commands.delete command
    end

### Private Instance Methods

load_and_instantiate(command_name) click to toggle source

    # File lib/rubygems/command_manager.rb, line 199
    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 Exception => e
        e = load_error if load_error

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