Add coverage for post model

Author: rsmithlal

spec/models/better_together/post_spec.rb

@@ -0,0 +1,38 @@
+# frozen_string_literal: true
+
+require 'rails_helper'
+
+RSpec.describe BetterTogether::Post, type: :model do
+  it_behaves_like 'an authorable model'
+
+  it 'has a valid factory' do
+    expect(build(:better_together_post)).to be_valid
+  end
+
+  it 'validates presence of title and content' do
+    post = build(:better_together_post, title: nil, content: nil)
+    expect(post).not_to be_valid
+    expect(post.errors[:title]).to include("can't be blank")
+    expect(post.errors[:content]).to include("can't be blank")
+  end
+
+  describe '#to_s' do
+    it 'returns the title' do
+      post = build(:better_together_post, title: 'Example')
+      expect(post.to_s).to eq 'Example'
+    end
+  end
+
+  describe 'after_create #add_creator_as_author' do
+    it 'creates an authorship for the creator_id' do
+      creator = create(:better_together_person)
+      post = build(:better_together_post)
+      # Ensure no prebuilt authorships from the factory
+      post.authorships.clear
+      post.creator_id = creator.id
+      post.save!
+
+      expect(post.authors.reload.map(&:id)).to include(creator.id)
+    end
+  end
+end