32 files changed, 214 insertions, 23 deletions

diff --git a/activerecord/test/models/aircraft.rb b/activerecord/test/models/aircraft.rb
index 1f35ef45da..c4404a8094 100644
--- a/activerecord/test/models/aircraft.rb
+++ b/activerecord/test/models/aircraft.rb
@@ -1,4 +1,5 @@
 class Aircraft < ActiveRecord::Base
   self.pluralize_table_names = false
   has_many :engines, :foreign_key => "car_id"
+  has_many :wheels, as: :wheelable
 end
diff --git a/activerecord/test/models/author.rb b/activerecord/test/models/author.rb
index 8c1f14bd36..0d90cbb110 100644
--- a/activerecord/test/models/author.rb
+++ b/activerecord/test/models/author.rb
@@ -144,9 +144,6 @@ class Author < ActiveRecord::Base
 
   has_many :posts_with_signature, ->(record) { where("posts.title LIKE ?", "%by #{record.name.downcase}%") }, class_name: "Post"
 
-  scope :relation_include_posts, -> { includes(:posts) }
-  scope :relation_include_tags,  -> { includes(:tags) }
-
   attr_accessor :post_log
   after_initialize :set_post_log
 
diff --git a/activerecord/test/models/book.rb b/activerecord/test/models/book.rb
index 2170018068..1927191393 100644
--- a/activerecord/test/models/book.rb
+++ b/activerecord/test/models/book.rb
@@ -10,6 +10,10 @@ class Book < ActiveRecord::Base
   enum status: [:proposed, :written, :published]
   enum read_status: {unread: 0, reading: 2, read: 3}
   enum nullable_status: [:single, :married]
+  enum language: [:english, :spanish, :french], _prefix: :in
+  enum author_visibility: [:visible, :invisible], _prefix: true
+  enum illustrator_visibility: [:visible, :invisible], _prefix: true
+  enum font_size: [:small, :medium, :large], _prefix: :with, _suffix: true
 
   def published!
     super
diff --git a/activerecord/test/models/bulb.rb b/activerecord/test/models/bulb.rb
index a6e83fe353..dc0296305a 100644
--- a/activerecord/test/models/bulb.rb
+++ b/activerecord/test/models/bulb.rb
@@ -1,6 +1,7 @@
 class Bulb < ActiveRecord::Base
   default_scope { where(:name => 'defaulty') }
   belongs_to :car, :touch => true
+  scope :awesome, -> { where(frickinawesome: true) }
 
   attr_reader :scope_after_initialize, :attributes_after_initialize
 
@@ -49,3 +50,9 @@ class FailedBulb < Bulb
     throw(:abort)
   end
 end
+
+class TrickyBulb < Bulb
+  after_create do |record|
+    record.car.bulbs.to_a
+  end
+end
diff --git a/activerecord/test/models/car.rb b/activerecord/test/models/car.rb
index 81263b79d1..778c22b1f6 100644
--- a/activerecord/test/models/car.rb
+++ b/activerecord/test/models/car.rb
@@ -4,6 +4,7 @@ class Car < ActiveRecord::Base
   has_many :funky_bulbs, class_name: 'FunkyBulb', dependent: :destroy
   has_many :failed_bulbs, class_name: 'FailedBulb', dependent: :destroy
   has_many :foo_bulbs, -> { where(:name => 'foo') }, :class_name => "Bulb"
+  has_many :awesome_bulbs, -> { awesome }, class_name: "Bulb"
 
   has_one :bulb
 
diff --git a/activerecord/test/models/carrier.rb b/activerecord/test/models/carrier.rb
new file mode 100644
index 0000000000..230be118c3
--- /dev/null
+++ b/activerecord/test/models/carrier.rb
@@ -0,0 +1,2 @@
+class Carrier < ActiveRecord::Base
+end
diff --git a/activerecord/test/models/categorization.rb b/activerecord/test/models/categorization.rb
index 6588531de6..4cd67c970a 100644
--- a/activerecord/test/models/categorization.rb
+++ b/activerecord/test/models/categorization.rb
@@ -1,6 +1,6 @@
 class Categorization < ActiveRecord::Base
   belongs_to :post
-  belongs_to :category
+  belongs_to :category, counter_cache: true
   belongs_to :named_category, :class_name => 'Category', :foreign_key => :named_category_name, :primary_key => :name
   belongs_to :author
 
diff --git a/activerecord/test/models/company.rb b/activerecord/test/models/company.rb
index 6961f8fd6f..1dcd9fc21e 100644
--- a/activerecord/test/models/company.rb
+++ b/activerecord/test/models/company.rb
@@ -10,7 +10,6 @@ class Company < AbstractCompany
   has_one :dummy_account, :foreign_key => "firm_id", :class_name => "Account"
   has_many :contracts
   has_many :developers, :through => :contracts
-  has_many :accounts
 
   scope :of_first_firm, lambda {
     joins(:account => :firm).
@@ -26,6 +25,9 @@ class Company < AbstractCompany
   def private_method
     "I am Jack's innermost fears and aspirations"
   end
+
+  class SpecialCo < Company
+  end
 end
 
 module Namespaced
@@ -83,6 +85,9 @@ class Firm < Company
 
   has_many :association_with_references, -> { references(:foo) }, :class_name => 'Client'
 
+  has_one :lead_developer, class_name: "Developer"
+  has_many :projects
+
   def log
     @log ||= []
   end
diff --git a/activerecord/test/models/contact.rb b/activerecord/test/models/contact.rb
index 3ea17c3abf..9f2f69e1ee 100644
--- a/activerecord/test/models/contact.rb
+++ b/activerecord/test/models/contact.rb
@@ -3,7 +3,7 @@ module ContactFakeColumns
     base.class_eval do
       establish_connection(:adapter => 'fake')
 
-      connection.tables = [table_name]
+      connection.data_sources = [table_name]
       connection.primary_keys = {
         table_name => 'id'
       }
diff --git a/activerecord/test/models/content.rb b/activerecord/test/models/content.rb
new file mode 100644
index 0000000000..140e1dfc78
--- /dev/null
+++ b/activerecord/test/models/content.rb
@@ -0,0 +1,40 @@
+class Content < ActiveRecord::Base
+  self.table_name = 'content'
+  has_one :content_position, dependent: :destroy
+
+  def self.destroyed_ids
+    @destroyed_ids ||= []
+  end
+
+  before_destroy do |object|
+    Content.destroyed_ids << object.id
+  end
+end
+
+class ContentWhichRequiresTwoDestroyCalls < ActiveRecord::Base
+  self.table_name = 'content'
+  has_one :content_position, foreign_key: 'content_id', dependent: :destroy
+
+  after_initialize do
+    @destroy_count = 0
+  end
+
+  before_destroy do
+    @destroy_count += 1
+    if @destroy_count == 1
+      throw :abort
+    end
+  end
+end
+
+class ContentPosition < ActiveRecord::Base
+  belongs_to :content, dependent: :destroy
+
+  def self.destroyed_ids
+    @destroyed_ids ||= []
+  end
+
+  before_destroy do |object|
+    ContentPosition.destroyed_ids << object.id
+  end
+end
diff --git a/activerecord/test/models/customer_carrier.rb b/activerecord/test/models/customer_carrier.rb
new file mode 100644
index 0000000000..37186903ff
--- /dev/null
+++ b/activerecord/test/models/customer_carrier.rb
@@ -0,0 +1,14 @@
+class CustomerCarrier < ActiveRecord::Base
+  cattr_accessor :current_customer
+
+  belongs_to :customer
+  belongs_to :carrier
+
+  default_scope -> {
+    if current_customer
+      where(customer: current_customer)
+    else
+      all
+    end
+  }
+end
diff --git a/activerecord/test/models/developer.rb b/activerecord/test/models/developer.rb
index d2a5a7fc49..9a907273f8 100644
--- a/activerecord/test/models/developer.rb
+++ b/activerecord/test/models/developer.rb
@@ -7,12 +7,16 @@ module DeveloperProjectsAssociationExtension2
 end
 
 class Developer < ActiveRecord::Base
+  self.ignored_columns = %w(first_name last_name)
+
   has_and_belongs_to_many :projects do
     def find_most_recent
       order("id DESC").first
     end
   end
 
+  belongs_to :mentor
+
   accepts_nested_attributes_for :projects
 
   has_and_belongs_to_many :shared_computers, class_name: "Computer"
@@ -50,6 +54,10 @@ class Developer < ActiveRecord::Base
   has_many :firms, :through => :contracts, :source => :firm
   has_many :comments, ->(developer) { where(body: "I'm #{developer.name}") }
   has_many :ratings, through: :comments
+  has_one :ship, dependent: :nullify
+
+  belongs_to :firm
+  has_many :contracted_projects, class_name: "Project"
 
   scope :jamises, -> { where(:name => 'Jamis') }
 
@@ -60,6 +68,9 @@ class Developer < ActiveRecord::Base
     developer.audit_logs.build :message => "Computer created"
   end
 
+  attr_accessor :last_name
+  define_attribute_method 'last_name'
+
   def log=(message)
     audit_logs.build :message => message
   end
diff --git a/activerecord/test/models/doubloon.rb b/activerecord/test/models/doubloon.rb
new file mode 100644
index 0000000000..2b11d128e2
--- /dev/null
+++ b/activerecord/test/models/doubloon.rb
@@ -0,0 +1,12 @@
+class AbstractDoubloon < ActiveRecord::Base
+  # This has functionality that might be shared by multiple classes.
+
+  self.abstract_class = true
+  belongs_to :pirate
+end
+
+class Doubloon < AbstractDoubloon
+  # This uses an abstract class that defines attributes and associations.
+
+  self.table_name = 'doubloons'
+end
diff --git a/activerecord/test/models/face.rb b/activerecord/test/models/face.rb
index 91e46f83e5..af76fea52c 100644
--- a/activerecord/test/models/face.rb
+++ b/activerecord/test/models/face.rb
@@ -1,7 +1,7 @@
 class Face < ActiveRecord::Base
   belongs_to :man, :inverse_of => :face
   belongs_to :polymorphic_man, :polymorphic => true, :inverse_of => :polymorphic_face
-  # Oracle identifier lengh is limited to 30 bytes or less, `polymorphic` renamed `poly`
+  # Oracle identifier length is limited to 30 bytes or less, `polymorphic` renamed `poly`
   belongs_to :poly_man_without_inverse, :polymorphic => true
   # These is a "broken" inverse_of for the purposes of testing
   belongs_to :horrible_man, :class_name => 'Man', :inverse_of => :horrible_face
diff --git a/activerecord/test/models/guitar.rb b/activerecord/test/models/guitar.rb
new file mode 100644
index 0000000000..cd068ff53d
--- /dev/null
+++ b/activerecord/test/models/guitar.rb
@@ -0,0 +1,4 @@
+class Guitar < ActiveRecord::Base
+  has_many :tuning_pegs, index_errors: true
+  accepts_nested_attributes_for :tuning_pegs
+end
diff --git a/activerecord/test/models/member.rb b/activerecord/test/models/member.rb
index dc0566d8a7..7693c6e515 100644
--- a/activerecord/test/models/member.rb
+++ b/activerecord/test/models/member.rb
@@ -26,6 +26,9 @@ class Member < ActiveRecord::Base
   has_many :current_memberships, -> { where :favourite => true }
   has_many :clubs, :through => :current_memberships
 
+  has_many :tenant_memberships
+  has_many :tenant_clubs, through: :tenant_memberships, class_name: 'Club', source: :club
+
   has_one :club_through_many, :through => :current_memberships, :source => :club
 
   belongs_to :admittable, polymorphic: true
diff --git a/activerecord/test/models/member_detail.rb b/activerecord/test/models/member_detail.rb
index 9d253aa126..157130986c 100644
--- a/activerecord/test/models/member_detail.rb
+++ b/activerecord/test/models/member_detail.rb
@@ -1,7 +1,8 @@
 class MemberDetail < ActiveRecord::Base
-  belongs_to :member, :inverse_of => false
+  belongs_to :member, inverse_of: false
   belongs_to :organization
-  has_one :member_type, :through => :member
+  has_one :member_type, through: :member
+  has_one :membership, through: :member
 
-  has_many :organization_member_details, :through => :organization, :source => :member_details
+  has_many :organization_member_details, through: :organization, source: :member_details
 end
diff --git a/activerecord/test/models/membership.rb b/activerecord/test/models/membership.rb
index df7167ee93..e181ba1f11 100644
--- a/activerecord/test/models/membership.rb
+++ b/activerecord/test/models/membership.rb
@@ -18,3 +18,18 @@ class SelectedMembership < Membership
     select("'1' as foo")
   end
 end
+
+class TenantMembership < Membership
+  cattr_accessor :current_member
+
+  belongs_to :member
+  belongs_to :club
+
+  default_scope -> {
+    if current_member
+      where(member: current_member)
+    else
+      all
+    end
+  }
+end
diff --git a/activerecord/test/models/mentor.rb b/activerecord/test/models/mentor.rb
new file mode 100644
index 0000000000..11f1e4bff8
--- /dev/null
+++ b/activerecord/test/models/mentor.rb
@@ -0,0 +1,3 @@
+class Mentor < ActiveRecord::Base
+  has_many :developers
+end
\ No newline at end of file
diff --git a/activerecord/test/models/node.rb b/activerecord/test/models/node.rb
new file mode 100644
index 0000000000..07dd2dbccb
--- /dev/null
+++ b/activerecord/test/models/node.rb
@@ -0,0 +1,5 @@
+class Node < ActiveRecord::Base
+  belongs_to :tree, touch: true
+  belongs_to :parent,   class_name: 'Node', touch: true, optional: true
+  has_many   :children, class_name: 'Node', foreign_key: :parent_id, dependent: :destroy
+end
diff --git a/activerecord/test/models/parrot.rb b/activerecord/test/models/parrot.rb
index b26035d944..ddc9dcaf29 100644
--- a/activerecord/test/models/parrot.rb
+++ b/activerecord/test/models/parrot.rb
@@ -21,9 +21,3 @@ end
 class DeadParrot < Parrot
   belongs_to :killer, :class_name => 'Pirate', foreign_key: :killer_id
 end
-
-class FunkyParrot < Parrot
-  before_destroy do
-    raise "before_destroy was called"
-  end
-end
diff --git a/activerecord/test/models/person.rb b/activerecord/test/models/person.rb
index ad12f00d42..a4a9c6b0d4 100644
--- a/activerecord/test/models/person.rb
+++ b/activerecord/test/models/person.rb
@@ -37,7 +37,6 @@ class Person < ActiveRecord::Base
   has_many :essays, primary_key: "first_name", foreign_key: "writer_id"
 
   scope :males,   -> { where(:gender => 'M') }
-  scope :females, -> { where(:gender => 'F') }
 end
 
 class PersonWithDependentDestroyJobs < ActiveRecord::Base
diff --git a/activerecord/test/models/post.rb b/activerecord/test/models/post.rb
index 052b1c9690..23cebe2602 100644
--- a/activerecord/test/models/post.rb
+++ b/activerecord/test/models/post.rb
@@ -98,11 +98,11 @@ class Post < ActiveRecord::Base
     end
   end
 
-  has_many :taggings_with_delete_all, :class_name => 'Tagging', :as => :taggable, :dependent => :delete_all
-  has_many :taggings_with_destroy, :class_name => 'Tagging', :as => :taggable, :dependent => :destroy
+  has_many :taggings_with_delete_all, :class_name => 'Tagging', :as => :taggable, :dependent => :delete_all, counter_cache: :taggings_with_delete_all_count
+  has_many :taggings_with_destroy, :class_name => 'Tagging', :as => :taggable, :dependent => :destroy, counter_cache: :taggings_with_destroy_count
 
-  has_many :tags_with_destroy, :through => :taggings, :source => :tag, :dependent => :destroy
-  has_many :tags_with_nullify, :through => :taggings, :source => :tag, :dependent => :nullify
+  has_many :tags_with_destroy, :through => :taggings, :source => :tag, :dependent => :destroy, counter_cache: :tags_with_destroy_count
+  has_many :tags_with_nullify, :through => :taggings, :source => :tag, :dependent => :nullify, counter_cache: :tags_with_nullify_count
 
   has_many :misc_tags, -> { where :tags => { :name => 'Misc' } }, :through => :taggings, :source => :tag
   has_many :funky_tags, :through => :taggings, :source => :tag
@@ -185,6 +185,7 @@ class SubStiPost < StiPost
 end
 
 class FirstPost < ActiveRecord::Base
+  self.inheritance_column = :disabled
   self.table_name = 'posts'
   default_scope { where(:id => 1) }
 
@@ -193,6 +194,7 @@ class FirstPost < ActiveRecord::Base
 end
 
 class PostWithDefaultInclude < ActiveRecord::Base
+  self.inheritance_column = :disabled
   self.table_name = 'posts'
   default_scope { includes(:comments) }
   has_many :comments, :foreign_key => :post_id
@@ -204,16 +206,35 @@ class PostWithSpecialCategorization < Post
 end
 
 class PostWithDefaultScope < ActiveRecord::Base
+  self.inheritance_column = :disabled
   self.table_name = 'posts'
   default_scope { order(:title) }
 end
 
+class PostWithPreloadDefaultScope < ActiveRecord::Base
+  self.table_name = 'posts'
+
+  has_many :readers, foreign_key: 'post_id'
+
+  default_scope { preload(:readers) }
+end
+
+class PostWithIncludesDefaultScope < ActiveRecord::Base
+  self.table_name = 'posts'
+
+  has_many :readers, foreign_key: 'post_id'
+
+  default_scope { includes(:readers) }
+end
+
 class SpecialPostWithDefaultScope < ActiveRecord::Base
+  self.inheritance_column = :disabled
   self.table_name = 'posts'
   default_scope { where(:id => [1, 5,6]) }
 end
 
 class PostThatLoadsCommentsInAnAfterSaveHook < ActiveRecord::Base
+  self.inheritance_column = :disabled
   self.table_name = 'posts'
   has_many :comments, class_name: "CommentThatAutomaticallyAltersPostBody", foreign_key: :post_id
 
@@ -223,6 +244,7 @@ class PostThatLoadsCommentsInAnAfterSaveHook < ActiveRecord::Base
 end
 
 class PostWithAfterCreateCallback < ActiveRecord::Base
+  self.inheritance_column = :disabled
   self.table_name = 'posts'
   has_many :comments, foreign_key: :post_id
 
@@ -232,6 +254,7 @@ class PostWithAfterCreateCallback < ActiveRecord::Base
 end
 
 class PostWithCommentWithDefaultScopeReferencesAssociation < ActiveRecord::Base
+  self.inheritance_column = :disabled
   self.table_name = 'posts'
   has_many :comment_with_default_scope_references_associations, foreign_key: :post_id
   has_one :first_comment, class_name: "CommentWithDefaultScopeReferencesAssociation", foreign_key: :post_id
diff --git a/activerecord/test/models/professor.rb b/activerecord/test/models/professor.rb
new file mode 100644
index 0000000000..7654eda0ef
--- /dev/null
+++ b/activerecord/test/models/professor.rb
@@ -0,0 +1,5 @@
+require_dependency 'models/arunit2_model'
+
+class Professor < ARUnit2Model
+  has_and_belongs_to_many :courses
+end
diff --git a/activerecord/test/models/project.rb b/activerecord/test/models/project.rb
index 7f42a4b1f8..efa8246f1e 100644
--- a/activerecord/test/models/project.rb
+++ b/activerecord/test/models/project.rb
@@ -1,4 +1,5 @@
 class Project < ActiveRecord::Base
+  belongs_to :mentor
   has_and_belongs_to_many :developers, -> { distinct.order 'developers.name desc, developers.id desc' }
   has_and_belongs_to_many :readonly_developers, -> { readonly }, :class_name => "Developer"
   has_and_belongs_to_many :non_unique_developers, -> { order 'developers.name desc, developers.id desc' }, :class_name => 'Developer'
@@ -11,6 +12,16 @@ class Project < ActiveRecord::Base
                             :before_remove => Proc.new {|o, r| o.developers_log << "before_removing#{r.id}"},
                             :after_remove => Proc.new {|o, r| o.developers_log << "after_removing#{r.id}"}
   has_and_belongs_to_many :well_payed_salary_groups, -> { group("developers.salary").having("SUM(salary) > 10000").select("SUM(salary) as salary") }, :class_name => "Developer"
+  belongs_to :firm
+  has_one :lead_developer, through: :firm, inverse_of: :contracted_projects
+
+  begin
+    previous_value, ActiveRecord::Base.belongs_to_required_by_default =
+      ActiveRecord::Base.belongs_to_required_by_default, true
+    has_and_belongs_to_many :developers_required_by_default, class_name: "Developer"
+  ensure
+    ActiveRecord::Base.belongs_to_required_by_default = previous_value
+  end
 
   attr_accessor :developers_log
   after_initialize :set_developers_log
diff --git a/activerecord/test/models/ship.rb b/activerecord/test/models/ship.rb
index 312caef604..e333b964ab 100644
--- a/activerecord/test/models/ship.rb
+++ b/activerecord/test/models/ship.rb
@@ -3,6 +3,7 @@ class Ship < ActiveRecord::Base
 
   belongs_to :pirate
   belongs_to :update_only_pirate, :class_name => 'Pirate'
+  belongs_to :developer, dependent: :destroy
   has_many :parts, :class_name => 'ShipPart'
   has_many :treasures
 
@@ -19,6 +20,18 @@ class Ship < ActiveRecord::Base
   end
 end
 
+class ShipWithoutNestedAttributes < ActiveRecord::Base
+  self.table_name = "ships"
+  has_many :prisoners, inverse_of: :ship, foreign_key: :ship_id
+  has_many :parts, class_name: "ShipPart", foreign_key: :ship_id
+
+  validates :name, presence: true
+end
+
+class Prisoner < ActiveRecord::Base
+  belongs_to :ship, autosave: true, class_name: "ShipWithoutNestedAttributes", inverse_of: :prisoners
+end
+
 class FamousShip < ActiveRecord::Base
   self.table_name = 'ships'
   belongs_to :famous_pirate
diff --git a/activerecord/test/models/shop_account.rb b/activerecord/test/models/shop_account.rb
new file mode 100644
index 0000000000..1580e8b20c
--- /dev/null
+++ b/activerecord/test/models/shop_account.rb
@@ -0,0 +1,6 @@
+class ShopAccount < ActiveRecord::Base
+  belongs_to :customer
+  belongs_to :customer_carrier
+
+  has_one :carrier, through: :customer_carrier
+end
diff --git a/activerecord/test/models/topic.rb b/activerecord/test/models/topic.rb
index f81ffe1d90..176bc79dc7 100644
--- a/activerecord/test/models/topic.rb
+++ b/activerecord/test/models/topic.rb
@@ -32,7 +32,7 @@ class Topic < ActiveRecord::Base
     end
   end
 
-  has_many :replies, :dependent => :destroy, :foreign_key => "parent_id"
+  has_many :replies, dependent: :destroy, foreign_key: "parent_id", autosave: true
   has_many :approved_replies, -> { approved }, class_name: 'Reply', foreign_key: "parent_id", counter_cache: 'replies_count'
 
   has_many :unique_replies, :dependent => :destroy, :foreign_key => "parent_id"
@@ -86,7 +86,7 @@ class Topic < ActiveRecord::Base
     end
 
     def destroy_children
-      self.class.delete_all "parent_id = #{id}"
+      self.class.where("parent_id = #{id}").delete_all
     end
 
     def set_email_address
diff --git a/activerecord/test/models/treasure.rb b/activerecord/test/models/treasure.rb
index ffc65466d5..63ff0c23ec 100644
--- a/activerecord/test/models/treasure.rb
+++ b/activerecord/test/models/treasure.rb
@@ -1,6 +1,7 @@
 class Treasure < ActiveRecord::Base
   has_and_belongs_to_many :parrots
   belongs_to :looter, :polymorphic => true
+  # No counter_cache option given
   belongs_to :ship
 
   has_many :price_estimates, :as => :estimate_of
diff --git a/activerecord/test/models/tree.rb b/activerecord/test/models/tree.rb
new file mode 100644
index 0000000000..dc29cccc9c
--- /dev/null
+++ b/activerecord/test/models/tree.rb
@@ -0,0 +1,3 @@
+class Tree < ActiveRecord::Base
+  has_many :nodes, dependent: :destroy
+end
diff --git a/activerecord/test/models/tuning_peg.rb b/activerecord/test/models/tuning_peg.rb
new file mode 100644
index 0000000000..1252d6dc1d
--- /dev/null
+++ b/activerecord/test/models/tuning_peg.rb
@@ -0,0 +1,4 @@
+class TuningPeg < ActiveRecord::Base
+  belongs_to :guitar
+  validates_numericality_of :pitch
+end
diff --git a/activerecord/test/models/vehicle.rb b/activerecord/test/models/vehicle.rb
new file mode 100644
index 0000000000..ef26170f1f
--- /dev/null
+++ b/activerecord/test/models/vehicle.rb
@@ -0,0 +1,7 @@
+class Vehicle < ActiveRecord::Base
+  self.abstract_class = true
+  default_scope -> { where("tires_count IS NOT NULL") }
+end
+
+class Bus < Vehicle
+end
\ No newline at end of file