In correction of the Gist - https://gist.github.com/rbarazi/337147

users_controller.rb

# This gist is the correct one taken from Book Beginning Rails 4. The gist they mentioned in the book accidentally contains wrong 
# code. Thus I created this gist, so that you can copy the code directly and move on.


class UsersController < ApplicationController
  before_action :set_user, only: [:show, :edit, :update, :destroy]

  def new
    @user = User.new
  end

  def create
    @user = User.new(user_params)
    if @user.save
      redirect_to articles_path, notice: 'User successfully added.'
    else
      render action: :new
    end
  end

  def edit
  end

  def update
    if @user.update(user_params)
      redirect_to articles_path, notice: 'Updated user information successfully.'
    else
      render action: 'edit'
    end
  end

  private

  def set_user
    @user = User.find(params[:id])
  end

  def user_params
    params
  end
end