Merge remote-tracking branch 'upstream/master' into toc

Conflicts:
	lib/gollum/frontend/app.rb
	lib/gollum/markup.rb
	test/test_markup.rb

lib/gollum/markup.rb

@@ -200,11 +200,29 @@ module Gollum
     # Returns the marked up String data.
     def process_tags(data)
       @tagmap.each do |id, tag|
-        data.gsub!(id, process_tag(tag))
+        # If it's preformatted, just put the tag back
+        if is_preformatted?(data, id)
+          data.gsub!(id, "[[#{tag}]]")
+        else
+          data.gsub!(id, process_tag(tag))
+        end
       end
       data
     end
 
+    # Find `id` within `data` and determine if it's within
+    # preformatted tags.
+    #
+    # data      - The String data (with placeholders).
+    # id        - The String SHA1 hash.
+    PREFORMATTED_TAGS = %w(code tt)
+    def is_preformatted?(data, id)
+      doc = Nokogiri::HTML::DocumentFragment.parse(data)
+      node = doc.search("[text()*='#{id}']").first
+      node && (PREFORMATTED_TAGS.include?(node.name) ||
+        node.ancestors.any? { |a| PREFORMATTED_TAGS.include?(a.name) })
+    end
+
     # Process a single tag into its final HTML form.
     #
     # tag       - The String tag contents (the stuff inside the double