Fix sorting article by update date

Fix #149

_config.yml

@@ -48,6 +48,8 @@ posts_overview:
 # Customize the archive view.
 # Options:
 #   - sort_updated: sort posts by last modification date instead of creation date.
+# Note: this does not work together with pagination, since the pagination
+# plugin will sort pages by date of creation.
 archive:
   sort_updated: false
 

layout/_partial/post/date.ejs

@@ -6,7 +6,7 @@
         (Updated: <time datetime="<%= date_xml(post.updated) %>" itemprop="dateModified"><%= date(post.updated, config.date_format) %></time>)
         <% } %>
       <% } else { %>
-        <% if (theme.posts_overview.sort_updated) { %>
+        <% if (is_home() && theme.posts_overview.sort_updated || is_archive() && theme.archive.sort_updated ) { %>
           <time datetime="<%= date_xml(post.updated) %>" itemprop="dateModified"><%= date(post.updated, config.date_format) %></time>
         <% } else { %>
           <time datetime="<%= date_xml(post.date) %>" itemprop="datePublished"><%= date(post.date, config.date_format) %></time>

layout/archive.ejs

@@ -4,7 +4,7 @@
     <% var change = false %>
     <% var field_sort = theme.archive.sort_updated ? 'updated' : 'date' %>
     <% page.posts.sort(field_sort, 'desc').each(function(post) { %>
-      <% var itemYear = date(post.date, 'YYYY') - 0 %>
+      <% var itemYear = date(post[field_sort], 'YYYY') - 0 %>
       <% change = year !== itemYear %>
       <% year = change ? itemYear : year %>
       <% if (change) { %>