Merge pull request #402 from fatkodima/optimize-revisions

Reduce db calls in #revisions method

lib/audited/auditor.rb

@@ -101,9 +101,15 @@ def without_auditing(&block)
       #   end
       #
       def revisions(from_version = 1)
-        audits = self.audits.from_version(from_version)
-        return [] if audits.empty?
-        audits.map(&:revision)
+        return [] if audits.from_version(from_version).empty?
+
+        loaded_audits = audits.select([:audited_changes, :version]).to_a
+        targeted_audits = loaded_audits.select { |audit| audit.version >= from_version }
+
+        targeted_audits.map do |audit|
+          ancestors = loaded_audits.select { |a| a.version <= audit.version  }
+          revision_with(reconstruct_attributes(ancestors).merge(version: audit.version))
+        end
       end
 
       # Get a specific revision specified by the version number, or +:previous+
@@ -230,6 +236,12 @@ def auditing_enabled
       def auditing_enabled=(val)
         self.class.auditing_enabled = val
       end
+
+      def reconstruct_attributes(audits)
+        attributes = {}
+        audits.each { |audit| attributes.merge!(audit.new_attributes) }
+        attributes
+      end
     end # InstanceMethods
 
     module AuditedClassMethods