How to print a controller as text in the rails console?

Question

I'd like to view Devise::RegistrationsController (out of curiosity, as I'll inherit from it as shown here)

I tried the obvious rails c then puts Devise::RegistrationsController and a few variations (e.g. .to_s) but no luck..

Is it available somewhere for viewing, and can I print it to the rails console to view it?

Answer 1

Pry which is a replacement console for IRB has built in source browsing.

Install the pry-rails gem and start the console with rails c and it will start up Pry instead of IRB.

You can then use show-source to view the source code of the gem right from the console:

max@pop-os ~/p/sandbox> rails c
Running via Spring preloader in process 29286
Loading development environment (Rails 6.0.2.1)
[1] pry(main)> show-source Devise::RegistrationsController

From: /home/linuxbrew/.linuxbrew/lib/ruby/gems/2.7.0/gems/devise-4.7.2/app/controllers/devise/registrations_controller.rb @ line 3:
Class name: Devise::RegistrationsController
Number of monkeypatches: 4. Use the `-a` option to display all available monkeypatches
Number of lines: 166

class Devise::RegistrationsController < DeviseController
  prepend_before_action :require_no_authentication, only: [:new, :create, :cancel]
  prepend_before_action :authenticate_scope!, only: [:edit, :update, :destroy]
  prepend_before_action :set_minimum_password_length, only: [:new, :edit]

  # GET /resource/sign_up
  def new
    build_resource
    yield resource if block_given?
    respond_with resource
  end

  # POST /resource
  def create
    build_resource(sign_up_params)

    resource.save
    yield resource if block_given?
    if resource.persisted?
      if resource.active_for_authentication?
        set_flash_message! :notice, :signed_up
        sign_up(resource_name, resource)
        respond_with resource, location: after_sign_up_path_for(resource)
      else
        set_flash_message! :notice, :"signed_up_but_#{resource.inactive_message}"
        expire_data_after_sign_in!
        respond_with resource, location: after_inactive_sign_up_path_for(resource)
      end
    else
      clean_up_passwords resource
      set_minimum_password_length
      respond_with resource
    end
  end
:

If you don't want to depend on Pry and stick with IRB you can cobble something together with Method#source_location and IO.readlines. But IMHO it seems like a waste of time