couple of bugfixes identified while importing from VB

app/models/post_analyzer.rb

@@ -75,7 +75,7 @@ class PostAnalyzer
       begin
         uri = URI.parse(u)
         host = uri.host
-        @linked_hosts[host] ||= 1
+        @linked_hosts[host] ||= 1 unless host.nil?
       rescue URI::InvalidURIError
         # An invalid URI does not count as a raw link.
         next
@@ -90,10 +90,10 @@ class PostAnalyzer
     return [] unless @raw.present?
     return @raw_links if @raw_links.present?
 
-    # Don't include @mentions in the link count
     @raw_links = []
 
     cooked_document.search("a").each do |l|
+      # Don't include @mentions in the link count
       next if l.attributes['href'].nil? || link_is_a_mention?(l)
       url = l.attributes['href'].to_s
       @raw_links << url

lib/pretty_text.rb

@@ -192,7 +192,7 @@ module PrettyText
         else
           l["rel"] = "nofollow"
         end
-      rescue URI::InvalidURIError
+      rescue URI::InvalidURIError, URI::InvalidComponentError
         # add a nofollow anyway
         l["rel"] = "nofollow"
       end

vendor/assets/javascripts/better_markdown.js

@@ -437,11 +437,15 @@
   };
 
   function escapeHTML( text ) {
+    if (text && text.length > 0) {
       return text.replace( /&/g, "&" )
                  .replace( /</g, "&lt;" )
                  .replace( />/g, "&gt;" )
                  .replace( /"/g, "&quot;" )
                  .replace( /'/g, "&#39;" );
+    } else {
+      return "";
+    }
   }
 
   function render_tree( jsonml ) {