add: modelconfig - object_changes_adaptor

lib/paper_trail/events/base.rb

@@ -289,6 +289,8 @@ def recordable_object_changes(changes)
           # `object_changes_adapter` expects a plain `Hash`, not a
           # `HashWithIndifferentAccess`.
           changes = PaperTrail.config.object_changes_adapter.diff(changes.to_hash)
+        elsif @record.class.paper_trail.object_changes_adapter&.respond_to?(:diff)
+          changes = @record.class.paper_trail.object_changes_adapter.diff(changes.to_hash)
         end
 
         if @record.class.paper_trail.version_class.object_changes_col_is_json?

lib/paper_trail/has_paper_trail.rb

@@ -57,6 +57,7 @@ module ClassMethods
       #   sets the `created_at` field for a new Version equal to the `updated_at`
       #   column of the model being updated. If you instead want `created_at` to
       #   populate with the current timestamp, set this option to `false`.
+      # - :object_changes_adapter - uses a custom object_changes.
       #
       # Plugins like the experimental `paper_trail-association_tracking` gem
       # may accept additional options.

lib/paper_trail/model_config.rb

@@ -120,6 +120,10 @@ def version_class
       @version_class ||= @model_class.version_class_name.constantize
     end
 
+    def object_changes_adapter
+      @model_class.object_changes_adapter
+    end
+
     private
 
     # @api private
@@ -253,5 +257,12 @@ def setup_options(options)
       end
       @model_class.paper_trail_options[:meta] ||= {}
     end
+
+    def setup_custom_object_changes_adapter(options)
+      @model_class.class_attribute :object_changes_adapter
+      @model_class.object_changes_adapter = options[:object_changes_adapter]
+
+      @model_class.send :attr_accessor, @model_class.object_changes_adapter
+    end
   end
 end