Add extra regression spec around #post_path.

spec/helpers/url_helper_spec.rb

@@ -0,0 +1,15 @@
+require 'spec_helper'
+
+describe UrlHelper do
+  include UrlHelper
+
+  describe '#post_path' do
+    it 'should prefix slug with published_at' do
+      post = stub(
+        :published_at => Date.new(2012,1,1),
+        :slug         => 'post'
+      )
+      post_path(post).should == '/2012/01/01/post'
+    end
+  end
+end