Do not load ActiveRecord too early

lib/database_cleaner/active_record.rb

@@ -1,7 +1,11 @@
-require 'database_cleaner/active_record/version'
+require 'active_record'
 require 'database_cleaner/core'
-require 'database_cleaner/active_record/transaction'
-require 'database_cleaner/active_record/truncation'
-require 'database_cleaner/active_record/deletion'
 
-DatabaseCleaner[:active_record].strategy = :transaction
+ActiveSupport.on_load(:active_record) do
+  require 'database_cleaner/active_record/base'
+  require 'database_cleaner/active_record/transaction'
+  require 'database_cleaner/active_record/truncation'
+  require 'database_cleaner/active_record/deletion'
+
+  DatabaseCleaner[:active_record].strategy = :transaction
+end

lib/database_cleaner/active_record/base.rb

@@ -1,4 +1,3 @@
-require 'active_record'
 require 'database_cleaner/strategy'
 require 'erb'
 require 'yaml'

lib/database_cleaner/active_record/deletion.rb

@@ -1,6 +1,3 @@
-require 'active_record'
-require 'database_cleaner/active_record/truncation'
-
 module DatabaseCleaner
   module ActiveRecord
     class Deletion < Truncation

lib/database_cleaner/active_record/transaction.rb

@@ -1,5 +1,3 @@
-require 'database_cleaner/active_record/base'
-
 module DatabaseCleaner
   module ActiveRecord
     class Transaction < Base

lib/database_cleaner/active_record/truncation.rb

@@ -1,5 +1,4 @@
 require "delegate"
-require 'database_cleaner/active_record/base'
 
 module DatabaseCleaner
   module ActiveRecord

spec/spec_helper.rb

@@ -18,6 +18,8 @@
 
 require 'database_cleaner-active_record'
 
+ActiveRecord::Base # load active record
+
 RSpec.configure do |config|
   # These two settings work together to allow you to limit a spec run
   # to individual examples or groups you care about by tagging them with