continue to raise on serializing an unsaved model to a delayed job

This capability got lost in the move to native YAML serialization.

refs #1

Change-Id: Id7ea4d635f74732d793c53f0fd34304730ade978
Reviewed-on: https://gerrit.instructure.com/2402
Reviewed-by: Bracken Mosbacker <bracken@instructure.com>
Tested-by: Hudson <hudson@instructure.com>

vendor/plugins/delayed_job/lib/delayed/performable_method.rb

@@ -18,6 +18,9 @@ class ActiveRecord::Base
   yaml_as "tag:ruby.yaml.org,2002:ActiveRecord"
 
   def to_yaml(opts = {})
+    if id.nil?
+      raise("Can't serialize unsaved ActiveRecord object for delayed job: #{self.inspect}")
+    end
     YAML.quick_emit(self.object_id, opts) do |out|
       out.scalar(taguri, id.to_s)
     end

vendor/plugins/delayed_job/spec/job_spec.rb

@@ -36,5 +36,14 @@ describe Delayed::Job do
       Delayed::Job.db_time_now.zone.should match(/CST|CDT/)
     end
   end
-  
+
+  it "should fail on job creation if an unsaved AR object is used" do
+    story = Story.new :text => "Once upon..."
+    lambda { story.send_later(:text) }.should raise_error
+
+    reader = StoryReader.new
+    lambda { reader.send_later(:read, story) }.should raise_error
+
+    lambda { [story, 1, story, false].send_later(:first) }.should raise_error
+  end
 end

vendor/plugins/delayed_job/spec/performable_method_spec.rb

@@ -38,8 +38,5 @@ describe Delayed::PerformableMethod do
     p.method.should  == :read
     p.args.should    == [story]
     p.perform.should == 'Epilog: Once upon...'
-  end                 
-  
-  
-  
+  end
 end