Sort blogposts and events instead of relying on filesystem sorting

lib/helpers/archives.rb

@@ -1,6 +1,11 @@
 module ArchiveHelper
   def academic_years
-    Set.new(items.find_all('/blog/*/*').map { |i| i.identifier.to_s[/\d\d-\d\d/] }).to_a
+    # Set.to_a to prevent duplicates
+    Set.new(items
+              .find_all('/blog/*/*')
+              .map { |i| i.identifier.to_s[/\d\d-\d\d/] })
+       .to_a
+       .sort
   end
 
   def academic_years_blog_items

lib/helpers/events.rb

@@ -22,7 +22,7 @@ module EventsHelper
   end
 
   def academic_years_event_items
-    items.find_all('/events/*').map { |e| [e[:academic_year], e] }.reverse
+    items.find_all('/events/*').map { |e| [e[:academic_year], e] }.sort_by(&:first)
   end
 
   def grouped_events

lib/helpers/preprocess.rb

@@ -1,8 +1,10 @@
 module PreprocessHelper
   def ignore_old_blogposts
     @items.delete_if do |item|
-      next unless item.identifier.to_s.start_with?('/blog/')
-      !item.identifier.to_s.start_with?('/blog/16-17/')
+      path = item.identifier.to_s
+      next unless path.start_with?('/blog/')
+      year = path.gsub(%r{/blog/(\d\d)-\d\d/.*}, '\1').to_i
+      year < 16
     end
   end