adds missing requires

activerecord/lib/active_record/coders/yaml_column.rb

 require 'yaml'
+require 'active_support/core_ext/regexp'
 
 module ActiveRecord
   module Coders # :nodoc:

activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb

@@ -9,6 +9,7 @@
 require 'active_record/connection_adapters/mysql/type_metadata'
 
 require 'active_support/core_ext/string/strip'
+require 'active_support/core_ext/regexp'
 
 module ActiveRecord
   module ConnectionAdapters

activerecord/lib/active_record/dynamic_matchers.rb

+require 'active_support/core_ext/regexp'
+
 module ActiveRecord
   module DynamicMatchers #:nodoc:
     def respond_to?(name, include_private = false)

activerecord/lib/active_record/migration.rb

-require "active_support/core_ext/module/attribute_accessors"
 require 'set'
+require "active_support/core_ext/module/attribute_accessors"
+require 'active_support/core_ext/regexp'
 
 module ActiveRecord
   class MigrationError < ActiveRecordError#:nodoc:

activerecord/lib/active_record/relation/delegation.rb

 require 'active_support/concern'
+require 'active_support/core_ext/regexp'
 
 module ActiveRecord
   module Delegation # :nodoc:

activerecord/lib/active_record/relation/query_methods.rb

@@ -4,6 +4,7 @@
 require "active_record/relation/where_clause_factory"
 require 'active_model/forbidden_attributes_protection'
 require 'active_support/core_ext/string/filters'
+require 'active_support/core_ext/regexp'
 
 module ActiveRecord
   module QueryMethods

activerecord/lib/active_record/sanitization.rb

+require 'active_support/core_ext/regexp'
+
 module ActiveRecord
   module Sanitization
     extend ActiveSupport::Concern

activerecord/lib/rails/generators/active_record/migration/migration_generator.rb

 require 'rails/generators/active_record'
+require 'active_support/core_ext/regexp'
 
 module ActiveRecord
   module Generators # :nodoc:

activerecord/test/cases/associations/left_outer_join_association_test.rb

@@ -5,6 +5,7 @@
 require 'models/essay'
 require 'models/categorization'
 require 'models/person'
+require 'active_support/core_ext/regexp'
 
 class LeftOuterJoinAssociationTest < ActiveRecord::TestCase
   fixtures :authors, :essays, :posts, :comments, :categorizations, :people

activerecord/test/cases/scoping/default_scoping_test.rb

@@ -5,6 +5,7 @@
 require 'models/computer'
 require 'models/vehicle'
 require 'models/cat'
+require 'active_support/core_ext/regexp'
 
 class DefaultScopingTest < ActiveRecord::TestCase
   fixtures :developers, :posts, :comments

activerecord/test/cases/test_case.rb

 require 'active_support/test_case'
 require 'active_support/testing/stream'
+require 'active_support/core_ext/regexp'
 
 module ActiveRecord
   # = Active Record Test Case