Merge pull request bywo#17 from byronmwong/feature/likes

create PostLike model and tests

Author: bywo

app/models/post.rb

@@ -1,4 +1,17 @@
 class Post < ActiveRecord::Base
   belongs_to :user
   belongs_to :group
+  has_many :post_likes, inverse_of: :post
+
+  def likes
+    post_likes
+  end
+
+  def add_like!(user)
+    likes.create!(user: user)
+  end
+
+  def remove_like!(user)
+    likes.find_by(user_id: user.id).destroy
+  end
 end

app/models/post_like.rb

@@ -0,0 +1,4 @@
+class PostLike < ActiveRecord::Base
+  belongs_to :post
+  belongs_to :user
+end

db/migrate/20140427230320_create_post_likes.rb

@@ -0,0 +1,10 @@
+class CreatePostLikes < ActiveRecord::Migration
+  def change
+    create_table :post_likes do |t|
+      t.belongs_to :post, index: true
+      t.belongs_to :user, index: true
+
+      t.timestamps
+    end
+  end
+end

db/schema.rb

@@ -11,7 +11,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 20140422120201) do
+ActiveRecord::Schema.define(version: 20140427230320) do
 
   # These are extensions that must be enabled in order to support this database
   enable_extension "plpgsql"
@@ -36,6 +36,16 @@
     t.datetime "updated_at"
   end
 
+  create_table "post_likes", force: true do |t|
+    t.integer  "post_id"
+    t.integer  "user_id"
+    t.datetime "created_at"
+    t.datetime "updated_at"
+  end
+
+  add_index "post_likes", ["post_id"], name: "index_post_likes_on_post_id", using: :btree
+  add_index "post_likes", ["user_id"], name: "index_post_likes_on_user_id", using: :btree
+
   create_table "posts", force: true do |t|
     t.string   "content"
     t.string   "type"

spec/models/post_like_spec.rb

@@ -0,0 +1,5 @@
+require 'spec_helper'
+
+describe PostLike do
+  pending "add some examples to (or delete) #{__FILE__}"
+end

spec/models/post_spec.rb

@@ -1,5 +1,35 @@
 require 'spec_helper'
 
 describe Post do
-  pending "add some examples to (or delete) #{__FILE__}"
+  let(:post) { FactoryGirl.create(:song_post) }
+
+  subject { post }
+
+  it { should respond_to(:group) }
+  it { should respond_to(:user) }
+  it { should respond_to(:post_likes) }
+  it { should respond_to(:likes) }
+
+  describe 'managing likes' do
+    let(:user) { FactoryGirl.create(:user) }
+    before { @like = post.add_like!(user) }
+
+    describe 'add new like' do
+      its(:likes) { should include(@like) }
+    end
+
+    describe 'new like' do
+      subject { @like }
+      its(:user) { should == user }
+    end
+
+    describe 'remove like' do
+      before { post.remove_like!(user) }
+      its(:likes) { should_not include(@like) }
+
+      it 'throws when removing unexisting like' do
+        expect { post.remove_like!(user) }.to raise_error()
+      end
+    end
+  end
 end