Fix feed link when post title contains HTML

lib/jekyll-feed/feed.xml

@@ -45,8 +45,10 @@
   {% endif %}
   {% for post in posts limit: 10 %}
     <entry{% if post.lang %}{{" "}}xml:lang="{{ post.lang }}"{% endif %}>
-      <title type="html">{{ post.title | smartify | strip_html | normalize_whitespace | xml_escape }}</title>
-      <link href="{{ post.url | absolute_url }}" rel="alternate" type="text/html" title="{{ post.title | xml_escape }}" />
+      {% assign post_title = post.title | smartify | strip_html | normalize_whitespace | xml_escape %}
+
+      <title type="html">{{ post_title }}</title>
+      <link href="{{ post.url | absolute_url }}" rel="alternate" type="text/html" title="{{ post_title }}" />
       <published>{{ post.date | date_to_xmlschema }}</published>
       <updated>{{ post.last_modified_at | default: post.date | date_to_xmlschema }}</updated>
       <id>{{ post.id | absolute_url | xml_escape }}</id>

spec/fixtures/_posts/2014-03-04-march-the-fourth.md

@@ -1,4 +1,5 @@
 ---
+title: <span class="highlight">Sparkling</span> Title
 tags:
  - '"/><VADER>'
 image:

spec/jekyll-feed_spec.rb

@@ -87,6 +87,10 @@
     expect(contents).to match '<title type="html">The plugin will properly strip newlines.</title>'
   end
 
+  it "strips HTML from link titles" do
+    expect(contents).to match %r!<link .* title="Sparkling Title" />!
+  end
+
   it "renders Liquid inside posts" do
     expect(contents).to match "Liquid is rendered."
     expect(contents).not_to match "Liquid is not rendered."