Impressionable now extends ActiveSupport::Concern. Adds pg gem to test_app.

app/models/impressionist/impressionable.rb

@@ -1,10 +1,6 @@
 module Impressionist
   module Impressionable
-
-    def self.included(base)
-      base.extend ClassMethods
-      base.send(:include, InstanceMethods)
-    end
+    extend ActiveSupport::Concern
 
     module ClassMethods
       attr_accessor :cache_options
@@ -28,7 +24,6 @@ module Impressionist
       end
     end
 
-    module InstanceMethods
     def impressionable?
       true
     end
@@ -66,6 +61,4 @@ module Impressionist
       impressionist_count({:start_date=>start_date, :end_date=>end_date, :filter=> :session_hash})
     end
   end
-
-  end
 end

test_app/Gemfile

@@ -2,11 +2,9 @@ source 'https://rubygems.org'
 
 gem 'rails', '3.2.2'
 
-# Bundle edge Rails instead:
-# gem 'rails', :git => 'git://github.com/rails/rails.git'
-
 gem 'impressionist', :path => '../'
 
+gem 'pg'
 gem 'sqlite3'
 
 gem 'json'