Add power_user? method to User model

app/controllers/posts_controller.rb

@@ -39,7 +39,7 @@ class PostsController < ApplicationController
   def update
     post = Post.find(params[:id])
     
-    if current_user.role == 'user' && current_user.id != post.user_id
+    if !current_user.power_user? && current_user.id != post.user_id
       render json: I18n.t('errors.unauthorized'), status: :unauthorized
       return
     end

app/models/user.rb

@@ -18,4 +18,8 @@ class User < ApplicationRecord
     gravatar_id = Digest::MD5::hexdigest(email.downcase)
     "https://secure.gravatar.com/avatar/#{gravatar_id}"
   end
+
+  def power_user?
+    role == 'admin' || role == 'moderator'
+  end
 end

app/views/posts/show.html.erb

@@ -5,7 +5,7 @@
       postId: @post.id,
       postStatuses: @post_statuses,
       isLoggedIn: user_signed_in?,
-      isPowerUser: user_signed_in? ? (current_user.role == 'admin' || current_user.role == 'moderator') : false,
+      isPowerUser: user_signed_in? ? current_user.power_user? : false,
       authenticityToken: form_authenticity_token,
     }
   )

spec/models/user_spec.rb

@@ -2,6 +2,8 @@ require 'rails_helper'
 
 RSpec.describe User, type: :model do
   let(:user) { FactoryBot.build(:user) }
+  let(:moderator) { FactoryBot.build(:moderator) }
+  let(:admin) { FactoryBot.build(:admin) }
 
   it 'should be valid' do
     expect(user).to be_valid
@@ -12,10 +14,6 @@ RSpec.describe User, type: :model do
   end
 
   it 'can have the following roles: "user", "moderator" and "admin"' do
-    user = FactoryBot.build(:user)
-    moderator = FactoryBot.build(:moderator)
-    admin = FactoryBot.build(:admin)
-
     expect(user.role).to eq('user')
     expect(moderator.role).to eq('moderator')
     expect(admin.role).to eq('admin')
@@ -50,4 +48,10 @@ RSpec.describe User, type: :model do
 
     expect(invalid_email_user).to be_invalid
   end
+
+  it 'knows if it is a power user' do
+    expect(user).not_to be_a_power_user
+    expect(moderator).to be_a_power_user
+    expect(admin).to be_a_power_user
+  end
 end