# class IRB::Command::Help

### Public Instance Methods

execute(command_name) click to toggle source

    # File lib/irb/command/help.rb, line 9
    def execute(command_name)
      content =
        if command_name.empty?
          help_message
        else
          if command_class = Command.load_command(command_name)
            command_class.help_message || command_class.description
          else
            "Can't find command `#{command_name}`. Please check the command name and try again.\n\n"
          end
        end
      Pager.page_content(content)
    end

### Private Instance Methods

add_category_to_output(category, cmds, output, longest_cmd_name_length) click to toggle source

    # File lib/irb/command/help.rb, line 72
    def add_category_to_output(category, cmds, output, longest_cmd_name_length)
      output.puts Color.colorize(category, [:BOLD])

      cmds.each do |cmd|
        output.puts "  #{cmd[:display_name].to_s.ljust(longest_cmd_name_length)}    #{cmd[:description]}"
      end

      output.puts
    end

help_message() click to toggle source

    # File lib/irb/command/help.rb, line 25
    def help_message
      commands_info = IRB::Command.all_commands_info
      helper_methods_info = IRB::HelperMethod.all_helper_methods_info
      commands_grouped_by_categories = commands_info.group_by { |cmd| cmd[:category] }
      commands_grouped_by_categories["Helper methods"] = helper_methods_info

      if irb_context.with_debugger
        # Remove the original "Debugging" category
        commands_grouped_by_categories.delete("Debugging")
      end

      longest_cmd_name_length = commands_info.map { |c| c[:display_name].length }.max

      output = StringIO.new

      help_cmds = commands_grouped_by_categories.delete("Help")
      no_category_cmds = commands_grouped_by_categories.delete("No category")
      aliases = irb_context.instance_variable_get(:@user_aliases).map do |alias_name, target|
        { display_name: alias_name, description: "Alias for `#{target}`" }
      end

      # Display help commands first
      add_category_to_output("Help", help_cmds, output, longest_cmd_name_length)

      # Display the rest of the commands grouped by categories
      commands_grouped_by_categories.each do |category, cmds|
        add_category_to_output(category, cmds, output, longest_cmd_name_length)
      end

      # Display commands without a category
      if no_category_cmds
        add_category_to_output("No category", no_category_cmds, output, longest_cmd_name_length)
      end

      # Display aliases
      add_category_to_output("Aliases", aliases, output, longest_cmd_name_length)

      # Append the debugger help at the end
      if irb_context.with_debugger
        # Add "Debugging (from debug.gem)" category as title
        add_category_to_output("Debugging (from debug.gem)", [], output, longest_cmd_name_length)
        output.puts DEBUGGER__.help
      end

      output.string
    end