Gem::CommandManager#load_and_instantiate

# File tmp/rubies/ruby-4.0.0/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"

  begin
    begin
      require "rubygems/commands/#{command_name}_command"
    rescue LoadError
      # it may have been defined from a rubygems_plugin.rb file
    end

    Gem::Commands.const_get(const_name).new
  rescue StandardError => e
    alert_error clean_text("Loading command: #{command_name} (#{e.class})\n\t#{e}")
    ui.backtrace e
  end
end