Swapping in :select for :keep_if on changes array in :changes_for_paper_trail method for Ruby1.8.7 compatibility. Close #206

CHANGELOG.md

@@ -1,5 +1,6 @@
 ## 2.7.1 (Unreleased)
 
+  - [#206](https://github.com/airblade/paper_trail/issues/206) - Fixed Ruby 1.8.7 compatibility for tracking `object_changes`.
   - [#200](https://github.com/airblade/paper_trail/issues/200) - Fixed `next_version` method so that it returns the live model
     when called on latest reified version of a model prior to the live model.
   - [#197](https://github.com/airblade/paper_trail/issues/197) - PaperTrail now falls back on using YAML for serialization of

lib/paper_trail/has_paper_trail.rb

@@ -217,7 +217,7 @@ module PaperTrail
       end
 
       def changes_for_paper_trail
-        self.changes.keep_if do |key, value|
+        self.changes.select do |key, value|
           notably_changed.include?(key)
         end.tap do |changes|
           self.class.serialize_attribute_changes(changes) # Use serialized value for attributes when necessary