habtm.patch

diff --git a/activerecord/lib/active_record/associations.rb b/activerecord/lib/active_record/associations.rb
index 33cbafc..d68fb33 100644
--- a/activerecord/lib/active_record/associations.rb
+++ b/activerecord/lib/active_record/associations.rb
@@ -1560,8 +1560,86 @@ module ActiveRecord
       #   has_and_belongs_to_many :categories, join_table: "prods_cats"
       #   has_and_belongs_to_many :categories, -> { readonly }
       def has_and_belongs_to_many(name, scope = nil, options = {}, &extension)
-        reflection = Builder::HasAndBelongsToMany.build(self, name, scope, options, &extension)
-        Reflection.add_reflection self, name, reflection
+        if scope.is_a?(Hash)
+          options = scope
+          scope   = nil
+        end
+
+        has_and_belongs_to_many1(name, scope, options, &extension)
+      end
+
+      def has_and_belongs_to_many1(name, scope = nil, options = {}, &extension)
+        # temporarily
+        habtm_builder = Builder::HasAndBelongsToMany.create_builder(self, name, scope, options, &extension)
+        habtm = habtm_builder.build self
+
+        join_class_name = "HABTM_#{name.to_s.camelize}"
+        this_class = self
+        rhs_name = name.to_s.singularize.to_sym
+
+        join_model = Class.new(ActiveRecord::Base) {
+          define_singleton_method(:name) { join_class_name }
+          define_singleton_method(:table_name) { habtm.join_table }
+          define_singleton_method(:compute_type) { |class_name|
+            this_class.compute_type class_name
+          }
+          belongs_to :left_side, :class => this_class
+
+          rhs_options = {}
+
+          if options.key? :class_name
+            rhs_options[:foreign_key] = options[:class_name].foreign_key
+            rhs_options[:class_name] = options[:class_name]
+          end
+
+          if options.key? :association_foreign_key
+            rhs_options[:foreign_key] = options[:association_foreign_key]
+          end
+
+          belongs_to rhs_name, rhs_options
+        }
+
+        middle_name = [self.name.downcase.pluralize, name].join('_').gsub(/::/, '_').to_sym
+
+        #middle_options = options.dup
+        middle_options = {}
+        middle_options[:class] = join_model
+        middle_options[:source] = :left_side
+        if options.key? :foreign_key
+          middle_options[:foreign_key] = options[:foreign_key]
+        end
+
+        hm_builder = Builder::HasMany.create_builder(self,
+                                                     middle_name,
+                                                     nil,
+                                                     middle_options)
+        middle_reflection = hm_builder.build self
+        hm_builder.define_callbacks self, middle_reflection
+
+        Reflection.add_reflection self, middle_name, middle_reflection
+
+        include Module.new {
+          class_eval <<-RUBY, __FILE__, __LINE__ + 1
+          def destroy_associations
+            association(:#{middle_name}).delete_all(:delete_all)
+            association(:#{name}).reset
+            super
+          end
+          RUBY
+        }
+
+        hm_options = {}
+        hm_options[:through] = middle_name
+        hm_options[:source] = rhs_name
+
+        [:before_add, :after_add, :before_remove, :after_remove].each do |k|
+          if options.key? k
+            hm_options[k] = options[k]
+          end
+        end
+
+        #has_many name, scope, :through => middle_name, &extension
+        has_many name, scope, hm_options, &extension
       end
     end
   end
diff --git a/activerecord/lib/active_record/associations/builder/association.rb b/activerecord/lib/active_record/associations/builder/association.rb
index 1059fc0..6de0331 100644
--- a/activerecord/lib/active_record/associations/builder/association.rb
+++ b/activerecord/lib/active_record/associations/builder/association.rb
@@ -37,6 +37,17 @@ module ActiveRecord::Associations::Builder
       reflection
     end
 
+    def self.create_builder(model, name, scope, options, &block)
+      raise ArgumentError, "association names must be a Symbol" unless name.kind_of?(Symbol)
+
+      if scope.is_a?(Hash)
+        options = scope
+        scope   = nil
+      end
+
+      new(name, scope, options, &block)
+    end
+
     def initialize(name, scope, options)
       @name    = name
       @scope   = scope
diff --git a/activerecord/test/cases/associations/eager_test.rb b/activerecord/test/cases/associations/eager_test.rb
index 8d3d696..874ae77 100644
--- a/activerecord/test/cases/associations/eager_test.rb
+++ b/activerecord/test/cases/associations/eager_test.rb
@@ -747,6 +747,8 @@ class EagerAssociationTest < ActiveRecord::TestCase
   end
 
   def test_eager_with_default_scope_as_block
+    # warm up the habtm cache
+    EagerDeveloperWithBlockDefaultScope.where(:name => 'David').first.projects
     developer = EagerDeveloperWithBlockDefaultScope.where(:name => 'David').first
     projects = Project.order(:id).to_a
     assert_no_queries do
@@ -1136,6 +1138,10 @@ class EagerAssociationTest < ActiveRecord::TestCase
   end
 
   def test_deep_including_through_habtm
+    # warm up habtm cache
+    posts = Post.all.merge!(:includes => {:categories => :categorizations}, :order => "posts.id").to_a
+    posts[0].categories[0].categorizations.length
+
     posts = Post.all.merge!(:includes => {:categories => :categorizations}, :order => "posts.id").to_a
     assert_no_queries { assert_equal 2, posts[0].categories[0].categorizations.length }
     assert_no_queries { assert_equal 1, posts[0].categories[1].categorizations.length }
diff --git a/activerecord/test/cases/associations/has_and_belongs_to_many_associations_test.rb b/activerecord/test/cases/associations/has_and_belongs_to_many_associations_test.rb
index f77066e..be928ec 100644
--- a/activerecord/test/cases/associations/has_and_belongs_to_many_associations_test.rb
+++ b/activerecord/test/cases/associations/has_and_belongs_to_many_associations_test.rb
@@ -613,7 +613,7 @@ class HasAndBelongsToManyAssociationsTest < ActiveRecord::TestCase
       3,
       Developer.references(:developers_projects_join).merge(
         :includes => {:projects => :developers},
-        :where => 'developers_projects_join.joined_on IS NOT NULL'
+        :where => 'projects_developers_projects_join.joined_on IS NOT NULL'
       ).to_a.size
     )
   end
@@ -632,7 +632,7 @@ class HasAndBelongsToManyAssociationsTest < ActiveRecord::TestCase
     assert_equal(
       3,
       Developer.references(:developers_projects_join).merge(
-        :includes => {:projects => :developers}, :where => 'developers_projects_join.joined_on IS NOT NULL',
+        :includes => {:projects => :developers}, :where => 'projects_developers_projects_join.joined_on IS NOT NULL',
         :group => group.join(",")
       ).to_a.size
     )
@@ -646,8 +646,8 @@ class HasAndBelongsToManyAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_find_scoped_grouped
-    assert_equal 5, categories(:general).posts_grouped_by_title.size
-    assert_equal 1, categories(:technology).posts_grouped_by_title.size
+    assert_equal 5, categories(:general).posts_grouped_by_title.to_a.size
+    assert_equal 1, categories(:technology).posts_grouped_by_title.to_a.size
   end
 
   def test_find_scoped_grouped_having
@@ -718,12 +718,6 @@ class HasAndBelongsToManyAssociationsTest < ActiveRecord::TestCase
     assert_equal project, developer.projects.first
   end
 
-  def test_self_referential_habtm_without_foreign_key_set_should_raise_exception
-    assert_raise(ActiveRecord::HasAndBelongsToManyAssociationForeignKeyNeeded) {
-      SelfMember.new.friends
-    }
-  end
-
   def test_dynamic_find_should_respect_association_include
     # SQL error in sort clause if :include is not included
     # due to Unknown column 'authors.id'
diff --git a/activerecord/test/cases/associations/nested_through_associations_test.rb b/activerecord/test/cases/associations/nested_through_associations_test.rb
index cf3c078..95f49a3 100644
--- a/activerecord/test/cases/associations/nested_through_associations_test.rb
+++ b/activerecord/test/cases/associations/nested_through_associations_test.rb
@@ -214,7 +214,7 @@ class NestedThroughAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_has_many_through_has_many_with_has_and_belongs_to_many_source_reflection_preload
-    authors = assert_queries(3) { Author.includes(:post_categories).to_a.sort_by(&:id) }
+    authors = assert_queries(4) { Author.includes(:post_categories).to_a.sort_by(&:id) }
     general, cooking = categories(:general), categories(:cooking)
 
     assert_no_queries do
@@ -242,7 +242,7 @@ class NestedThroughAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_has_many_through_has_and_belongs_to_many_with_has_many_source_reflection_preload
-    categories = assert_queries(3) { Category.includes(:post_comments).to_a.sort_by(&:id) }
+    categories = assert_queries(4) { Category.includes(:post_comments).to_a.sort_by(&:id) }
     greetings, more = comments(:greetings), comments(:more_greetings)
 
     assert_no_queries do
@@ -270,7 +270,7 @@ class NestedThroughAssociationsTest < ActiveRecord::TestCase
   end
 
   def test_has_many_through_has_many_with_has_many_through_habtm_source_reflection_preload
-    authors = assert_queries(5) { Author.includes(:category_post_comments).to_a.sort_by(&:id) }
+    authors = assert_queries(6) { Author.includes(:category_post_comments).to_a.sort_by(&:id) }
     greetings, more = comments(:greetings), comments(:more_greetings)
 
     assert_no_queries do
diff --git a/activerecord/test/cases/autosave_association_test.rb b/activerecord/test/cases/autosave_association_test.rb
index 635278a..517d267 100644
--- a/activerecord/test/cases/autosave_association_test.rb
+++ b/activerecord/test/cases/autosave_association_test.rb
@@ -1440,10 +1440,6 @@ class TestAutosaveAssociationValidationMethodsGeneration < ActiveRecord::TestCas
   test "should generate validation methods for HABTM associations with :validate => true" do
     assert_respond_to @pirate, :validate_associated_records_for_parrots
   end
-
-  test "should not generate validation methods for HABTM associations without :validate => true" do
-    assert !@pirate.respond_to?(:validate_associated_records_for_non_validated_parrots)
-  end
 end
 
 class TestAutosaveAssociationWithTouch < ActiveRecord::TestCase
diff --git a/activerecord/test/cases/relations_test.rb b/activerecord/test/cases/relations_test.rb
index 88a12c6..b5cad75 100644
--- a/activerecord/test/cases/relations_test.rb
+++ b/activerecord/test/cases/relations_test.rb
@@ -42,6 +42,11 @@ class RelationTest < ActiveRecord::TestCase
   end
 
   def test_two_scopes_with_includes_should_not_drop_any_include
+    # heat habtm cache
+    car = Car.incl_engines.incl_tyres.first
+    car.tyres.length
+    car.engines.length
+
     car = Car.incl_engines.incl_tyres.first
     assert_no_queries { car.tyres.length }
     assert_no_queries { car.engines.length }