Add spec for `answer_share_url`

spec/helpers/social_helper_spec.rb

@@ -0,0 +1,33 @@
+# frozen_string_literal: true
+
+require "rails_helper"
+
+describe SocialHelper, type: :helper do
+  let(:user) { FactoryBot.create(:user) }
+  let(:answer) do
+    FactoryBot.create(
+      :answer,
+      user:,
+      content:          "this is an answer\nwith multiple lines\nand **FORMATTING**",
+      question_content: "this is a question .... or is it?"
+    )
+  end
+
+  before do
+    stub_const("APP_CONFIG", {
+                 "hostname"       => "example.com",
+                 "https"          => true,
+                 "items_per_page" => 5,
+               })
+  end
+
+  describe "#answer_share_url" do
+    subject { answer_share_url(answer) }
+
+    it "returns a proper share link" do
+      expect(subject).to eq(<<~URL.strip)
+        https://example.com/@#{answer.user.screen_name}/a/#{answer.id}
+      URL
+    end
+  end
+end