support anonymous classes on has_many associations

activerecord/lib/active_record/associations/builder/association.rb

@@ -17,7 +17,7 @@ module ActiveRecord::Associations::Builder
     end
     self.extensions = []
 
-    VALID_OPTIONS = [:class_name, :foreign_key, :validate]
+    VALID_OPTIONS = [:class_name, :class, :foreign_key, :validate]
 
     attr_reader :name, :scope, :options
 

activerecord/lib/active_record/reflection.rb

@@ -121,6 +121,7 @@ module ActiveRecord
         @scope         = scope
         @options       = options
         @active_record = active_record
+        @klass         = options[:class]
         @plural_name   = active_record.pluralize_table_names ?
                             name.to_s.pluralize : name.to_s
       end

activerecord/test/cases/associations/has_many_associations_test.rb

@@ -45,6 +45,24 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
     Client.destroyed_client_ids.clear
   end
 
+  def test_anonymous_has_many
+    developer = Class.new(ActiveRecord::Base) {
+      self.table_name = 'developers'
+      dev = self
+
+      developer_project = Class.new(ActiveRecord::Base) {
+        self.table_name = 'developers_projects'
+        belongs_to :developer, :class => dev
+      }
+      has_many :developer_projects, :class => developer_project, :foreign_key => 'developer_id'
+    }
+    dev = developer.first
+    named = Developer.find(dev.id)
+    assert_operator dev.developer_projects.count, :>, 0
+    assert_equal named.projects.map(&:id).sort,
+                 dev.developer_projects.map(&:project_id).sort
+  end
+
   def test_create_from_association_should_respect_default_scope
     car = Car.create(:name => 'honda')
     assert_equal 'honda', car.name