Add nicer syntax for simply copying attributes into revision metadata.

lib/acts_as_revisionable.rb

@@ -5,10 +5,6 @@ module ActsAsRevisionable
 
   autoload :RevisionRecord, File.expand_path('../acts_as_revisionable/revision_record', __FILE__)
 
-  def self.included(base)
-    base.extend(ActsMethods)
-  end
-
   module ActsMethods
     # Calling acts_as_revisionable will inject the revisionable behavior into the class. Specifying a :limit option
     # will limit the number of revisions that are kept per record. Specifying :minimum_age will ensure that revisions are
@@ -39,6 +35,11 @@ module ActsMethods
     #     :version => 1
     #   }
     #
+    # As a shortcut, you can can also just pass an attribute name or array of attribute names to copy to the revision
+    # record.
+    #
+    #   acts_as_revisionable :meta => :updated_by
+    #
     # The values to the <tt>:meta</tt> hash can be either symbols or Procs. If it is a symbol, the method
     # so named will be called on the record being revisioned. If it is a Proc, it will be called with the
     # record as the argument. Any other class will be sent directly to the revision record.
@@ -248,14 +249,14 @@ def create_revision!
       revision = revision_record_class.new(self, revision_options[:encoding])
       if revision_options[:meta].is_a?(Hash)
         revision_options[:meta].each do |attribute, value|
-          case value
-          when Symbol
-            value = self.send(value)
-          when Proc
-            value = value.call(self)
-          end
-          revision.send("#{attribute}=", value)
+          set_revision_meta_attribute(revision, attribute, value)
         end
+      elsif revision_options[:meta].is_a?(Array)
+        revision_options[:meta].each do |attribute|
+          set_revision_meta_attribute(revision, attribute, attribute.to_sym)
+        end
+      elsif revision_options[:meta]
+        set_revision_meta_attribute(revision, revision_options[:meta], revision_options[:meta].to_sym)
       end
       revision.save!
       return revision
@@ -299,7 +300,18 @@ def update_with_revision
         update_without_revision
       end
     end
+
+    # Set an attribute based on a meta argument
+    def set_revision_meta_attribute(revision, attribute, value)
+      case value
+      when Symbol
+        value = self.send(value)
+      when Proc
+        value = value.call(self)
+      end
+      revision.send("#{attribute}=", value)
+    end
   end
 end
 
-ActiveRecord::Base.send(:include, ActsAsRevisionable)
+ActiveRecord::Base.extend(ActsAsRevisionable::ActsMethods)

spec/acts_as_revisionable_spec.rb

@@ -143,7 +143,7 @@ class RevisionableSubclassModel < RevisionableNamespaceModel
 
   context "injected methods" do
     it "should be able to inject revisionable behavior onto ActiveRecord::Base" do
-      ActiveRecord::Base.included_modules.should include(ActsAsRevisionable)
+      ActiveRecord::Base.should respond_to(:acts_as_revisionable)
     end
 
     it "should add as has_many :record_revisions association" do
@@ -275,8 +275,8 @@ class RevisionableSubclassModel < RevisionableNamespaceModel
       record_1.create_revision!
       ActsAsRevisionable::RevisionRecord.count.should == 1
     end
-  
-    it "should set metadata on the revison when creating a revision record" do
+
+    it "should set metadata on the revison when creating a revision record using a complex attribute to value mapping" do
       record_1 = OtherRevisionableTestModel.create!(:name => "test", :updated_by => "dude")
       RevisionRecord2.count.should == 0
       record_1.create_revision!
@@ -286,6 +286,38 @@ class RevisionableSubclassModel < RevisionableNamespaceModel
       revision.updated_by.should == "dude"
       revision.version.should == 1
     end
+
+    it "should set metadata on the revison when creating a revision record using a simply string to define a method to copy" do
+      meta_value = OtherRevisionableTestModel.acts_as_revisionable_options[:meta]
+      begin
+        OtherRevisionableTestModel.acts_as_revisionable_options[:meta] = "label"
+        record_1 = OtherRevisionableTestModel.create!(:name => "test", :updated_by => "dude")
+        record_1.stub!(:label => "this is a label")
+        record_1.create_revision!
+        revision = record_1.last_revision
+        revision.label.should == "this is a label"
+        revision.updated_by.should == nil
+        revision.version.should == nil
+      ensure
+        OtherRevisionableTestModel.acts_as_revisionable_options[:meta] = meta_value
+      end
+    end
+
+    it "should set metadata on the revison when creating a revision record using an array of attribute names to copy" do
+      meta_value = OtherRevisionableTestModel.acts_as_revisionable_options[:meta]
+      begin
+        OtherRevisionableTestModel.acts_as_revisionable_options[:meta] = [:label, "version"]
+        record_1 = OtherRevisionableTestModel.create!(:name => "test", :updated_by => "dude")
+        record_1.stub!(:label => "this is a label", :version => 100)
+        record_1.create_revision!
+        revision = record_1.last_revision
+        revision.label.should == "this is a label"
+        revision.updated_by.should == nil
+        revision.version.should == 100
+      ensure
+        OtherRevisionableTestModel.acts_as_revisionable_options[:meta] = meta_value
+      end
+    end
 
     it "should not create a revision entry if revisioning is disabled" do
       record = RevisionableTestModel.create!(:name => "test")