Add specs and refactor ArticleDecorator#authors

app/decorators/article_decorator.rb

@@ -2,17 +2,15 @@ class ArticleDecorator < ApplicationDecorator
   delegate_all
 
   def authors
-    output = "#{author.link_tag} #{created_at_tag} "
+    output = [author.link_tag, created_at_tag]
 
     if editor && updated_at_tag
-      if editor.id != source.author_id
-        output << "and updated by #{editor_email_tag} on #{updated_at_tag}"
-      else
-        output << "and updated on #{updated_at_tag}"
-      end
+      output << "and updated"
+      output << "by #{editor_email_tag}" if editor.id != source.author_id
+      output << "on #{updated_at_tag}"
     end
 
-    output.html_safe
+    output.join(" ").html_safe
   end
 
   def title

spec/decorators/article_decorator_spec.rb

@@ -1,4 +1,56 @@
 require "rails_helper"
 
 RSpec.describe ArticleDecorator do
+  describe "#authors" do
+    let(:author) { create(:user) }
+    let(:expected_author_with_created_at) do
+      "#{subject.author.link_tag} #{subject.created_at_tag}"
+    end
+    subject { described_class.new(article) }
+
+    context "without an editor" do
+      let(:article) { create(:article, created_at: Time.at(0), author: author) }
+
+      it "displays a link to the author and the created_at time" do
+        expect(subject.authors).to eq(expected_author_with_created_at)
+      end
+    end
+
+    context "with an editor who is also the author" do
+      let(:article) do
+        create(
+          :article,
+          created_at: Time.at(0),
+          updated_at: Time.at(1),
+          author: author,
+          editor: author
+        )
+      end
+
+      it "displays a link to the author, created_at time and the updated at time" do
+        expect(subject.authors).to eq(
+          "#{expected_author_with_created_at} and updated on #{subject.updated_at_tag}"
+        )
+      end
+    end
+
+    context "with an editor who is not the author" do
+      let(:editor) { create(:user) }
+      let(:article) do
+        create(
+          :article,
+          created_at: Time.at(0),
+          updated_at: Time.at(1),
+          author: author,
+          editor: editor
+        )
+      end
+
+      it "displays a link to the author, created_at time and the editor with updated at time" do
+        expect(subject.authors).to eq(
+          "#{expected_author_with_created_at} and updated by #{subject.editor_email_tag} on #{subject.updated_at_tag}"
+        )
+      end
+    end
+  end
 end