adds InappropiateFlag model with relations and specs

app/models/comment.rb

@@ -11,6 +11,8 @@ class Comment < ActiveRecord::Base
   belongs_to :commentable, polymorphic: true
   belongs_to :user
 
+  has_many :inappropiate_flags, :as => :flaggable
+
   default_scope { includes(:user) }
   scope :recent, -> { order(id: :desc) }
 

app/models/debate.rb

@@ -12,6 +12,7 @@ class Debate < ActiveRecord::Base
   acts_as_paranoid column: :hidden_at
 
   belongs_to :author, class_name: 'User', foreign_key: 'author_id'
+  has_many :inappropiate_flags, :as => :flaggable
 
   validates :title, presence: true
   validates :description, presence: true

app/models/inappropiate_flag.rb

@@ -0,0 +1,41 @@
+class InappropiateFlag < ActiveRecord::Base
+
+  belongs_to :user
+  belongs_to :flaggable, polymorphic: true, counter_cache: true, touch: :flagged_as_inappropiate_at
+
+  scope(:by_user_and_flaggable, lambda do |user, flaggable|
+    where(user_id: user.id,
+          flaggable_type: flaggable.class.to_s,
+          flaggable_id: flaggable.id)
+  end)
+
+
+  class AlreadyFlaggedError < StandardError
+    def initialize
+      super "The flaggable was already flagged as inappropiate by this user"
+    end
+  end
+
+  class NotFlaggedError < StandardError
+    def initialize
+      super "The flaggable was not flagged as inappropiate by this user"
+    end
+  end
+
+
+  def self.flag!(user, flaggable)
+    raise AlreadyFlaggedError if flagged?(user, flaggable)
+    create(user: user, flaggable: flaggable)
+  end
+
+  def self.unflag!(user, flaggable)
+    flags = by_user_and_flaggable(user, flaggable)
+    raise NotFlaggedError if flags.empty?
+    flags.destroy_all
+  end
+
+  def self.flagged?(user, flaggable)
+    by_user_and_flaggable(user, flaggable).exists?
+  end
+
+end

app/models/user.rb

@@ -8,6 +8,7 @@ class User < ActiveRecord::Base
   has_one :administrator
   has_one :moderator
   has_one :organization
+  has_many :inappropiate_flags
 
   validates :first_name, presence: true, if: :use_first_name?
   validates :last_name,  presence: true, if: :use_last_name?

spec/models/inappropiate_flag_spec.rb

@@ -0,0 +1,64 @@
+require 'rails_helper'
+
+describe InappropiateFlag do
+
+  let(:user) { create(:user) }
+  let(:comment) { create(:comment) }
+
+  describe '.flag!' do
+
+    it 'creates a flag when there is none' do
+      expect { described_class.flag!(user, comment) }.to change{ InappropiateFlag.count }.by(1)
+      expect(InappropiateFlag.last.user).to eq(user)
+      expect(InappropiateFlag.last.flaggable).to eq(comment)
+    end
+
+    it 'raises an error if the flag has already been created' do
+      described_class.flag!(user, comment)
+      expect { described_class.flag!(user, comment) }.to raise_error(InappropiateFlag::AlreadyFlaggedError)
+    end
+
+    it 'increases the flag count' do
+      expect { described_class.flag!(user, comment) }.to change{ comment.reload.inappropiate_flags_count }.by(1)
+    end
+
+    it 'updates the flagged_as date' do
+      expect { described_class.flag!(user, comment) }.to change{ comment.reload.flagged_as_inappropiate_at }
+    end
+  end
+
+  describe '.unflag!' do
+    it 'raises an error if the flag does not exist' do
+      expect { described_class.unflag!(user, comment) }.to raise_error(InappropiateFlag::NotFlaggedError)
+    end
+
+    describe 'when the flag already exists' do
+      before(:each) { described_class.flag!(user, comment) }
+
+      it 'removes an existing flag' do
+        expect { described_class.unflag!(user, comment) }.to change{ InappropiateFlag.count }.by(-1)
+      end
+
+      it 'decreases the flag count' do
+        expect { described_class.unflag!(user, comment) }.to change{ comment.reload.inappropiate_flags_count }.by(-1)
+      end
+
+      it 'does not update the flagged_as date' do
+        expect { described_class.unflag!(user, comment) }.to_not change{ comment.flagged_as_inappropiate_at }
+      end
+    end
+
+  end
+
+  describe '.flagged?' do
+    it 'returns false when the user has not flagged the comment' do
+      expect(described_class.flagged?(user, comment)).to_not be
+    end
+
+    it 'returns true when the user has flagged the comment' do
+      described_class.flag!(user, comment)
+      expect(described_class.flagged?(user, comment)).to be
+    end
+  end
+
+end