Merge pull request #135 from leouofa/article-links

added specs for article links

app/models/article.rb

@@ -20,7 +20,19 @@ class Article < ApplicationRecord
 
   has_neighbors :embedding
 
+  has_many :article_links
+  has_many :linked_articles, through: :article_links, source: :linked_article, source_type: 'Article'
+
   validates :name, :description, :original_text, presence: true
+  validate :linked_articles_count_within_limit
 
   scope :without_embedding, -> { where(embedding: nil) }
+
+  private
+
+  def linked_articles_count_within_limit
+    return unless linked_articles.size > 3
+
+    errors.add(:linked_articles, "cannot exceed 3")
+  end
 end

app/models/article_link.rb

@@ -0,0 +1,14 @@
+class ArticleLink < ApplicationRecord
+  belongs_to :article
+  belongs_to :linked_article, polymorphic: true
+
+  validate :article_cannot_link_to_itself
+
+  private
+
+  def article_cannot_link_to_itself
+    return unless article_id == linked_article_id
+
+    errors.add(:linked_article, "can't be the same as the article")
+  end
+end

db/migrate/20240630010230_create_article_links.rb

@@ -0,0 +1,10 @@
+class CreateArticleLinks < ActiveRecord::Migration[7.0]
+  def change
+    create_table :article_links do |t|
+      t.references :article, null: false, foreign_key: true
+      t.references :linked_article, polymorphic: true, null: false
+
+      t.timestamps
+    end
+  end
+end

spec/factories/articles.rb

@@ -0,0 +1,13 @@
+FactoryBot.define do
+  factory :article do
+    association :pillar_column
+    sequence(:name) { |n| "Sample Article #{n}" }
+    description { "This is a sample article." }
+    original_text { "Some original text." }
+  end
+
+  factory :article_link do
+    association :article
+    association :linked_article, factory: :article
+  end
+end

spec/models/article_link_spec.rb

@@ -0,0 +1,15 @@
+require 'rails_helper'
+
+RSpec.describe ArticleLink, type: :model do
+  it "is valid with valid attributes" do
+    article_link = create(:article_link)
+    expect(article_link).to be_valid
+  end
+
+  it "is invalid if an article links to itself" do
+    article = create(:article)
+    article_link = build(:article_link, article: article, linked_article: article)
+    expect(article_link).not_to be_valid
+    expect(article_link.errors[:linked_article]).to include("can't be the same as the article")
+  end
+end

spec/models/articles_spec.rb

@@ -0,0 +1,39 @@
+require 'rails_helper'
+
+RSpec.describe Article, type: :model do
+  it "is valid with valid attributes" do
+    article = create(:article)
+    expect(article).to be_valid
+  end
+
+  it "is invalid without a name" do
+    article = build(:article, name: nil)
+    expect(article).not_to be_valid
+  end
+
+  it "is invalid without a description" do
+    article = build(:article, description: nil)
+    expect(article).not_to be_valid
+  end
+
+  it "is invalid without original text" do
+    article = build(:article, original_text: nil)
+    expect(article).not_to be_valid
+  end
+
+  it "cannot have more than 3 linked articles" do
+    article = create(:article)
+    3.times { article.linked_articles << create(:article) }
+    expect(article).to be_valid
+
+    article.linked_articles << create(:article)
+    expect(article).not_to be_valid
+  end
+
+  it "cannot link to itself" do
+    article = create(:article)
+    article_link = build(:article_link, article: article, linked_article: article)
+    expect(article_link).not_to be_valid
+    expect(article_link.errors[:linked_article]).to include("can't be the same as the article")
+  end
+end