Merge branch 'master' into refactor_proforma_import_export

# Conflicts:
#	spec/controllers/exercises_controller_spec.rb

app/controllers/exercises_controller.rb

@@ -59,7 +59,7 @@ raise: false
   end
 
   def collect_paths(files)
-    unique_paths = files.map(&:path).reject(&:blank?).uniq
+    unique_paths = files.map(&:path).compact_blank.uniq
     subpaths = unique_paths.map do |path|
       Array.new((path.split('/').length + 1)) do |n|
         path.split('/').shift(n).join('/')
@@ -321,7 +321,7 @@ raise: false
     @search = Search.new
     @search.exercise = @exercise
     @submission = current_user.submissions.where(exercise_id: @exercise.id).order('created_at DESC').first
-    @files = (@submission ? @submission.collect_files : @exercise.files).select(&:visible).sort_by(&:name_with_extension)
+    @files = (@submission ? @submission.collect_files : @exercise.files).select(&:visible).sort_by(&:filepath)
     @paths = collect_paths(@files)
 
     @user_id = if current_user.respond_to? :external_id