Support conditional paper trail on destroy

lib/paper_trail/has_paper_trail.rb

@@ -72,7 +72,7 @@ module PaperTrail
 
         after_create  :record_create, :if => :save_version? if !options[:on] || options[:on].include?(:create)
         before_update :record_update, :if => :save_version? if !options[:on] || options[:on].include?(:update)
-        after_destroy :record_destroy if !options[:on] || options[:on].include?(:destroy)
+        after_destroy :record_destroy, :if => :save_version? if !options[:on] || options[:on].include?(:destroy)
       end
 
       # Switches PaperTrail off for this class.

test/unit/model_test.rb

@@ -79,6 +79,15 @@ class HasPaperTrailModelTest < ActiveSupport::TestCase
         setup { @translation.update_attributes :content => 'Content' }
         should_not_change('the number of versions') { Version.count }
       end
+
+      context 'after destroy' do
+        setup do
+          @translation.save!
+          @translation.destroy
+        end
+
+        should_not_change('the number of versions') { Version.count }
+      end
     end
 
     context 'for US translations' do
@@ -107,6 +116,15 @@ class HasPaperTrailModelTest < ActiveSupport::TestCase
           setup { @translation.update_attributes :content => 'Content' }
           should_change('the number of versions', :by => 1) { Version.count }
         end
+
+        context 'after destroy' do
+          setup do
+            @translation.save!
+            @translation.destroy
+          end
+
+          should_change('the number of versions', :by => 1) { Version.count }
+        end
       end
     end
   end