1 files changed, 6 insertions, 18 deletions
diff --git a/activerecord/lib/active_record/associations/builder/collection_association.rb b/activerecord/lib/active_record/associations/builder/collection_association.rb
index bc15a49996..2ff67f904d 100644
--- a/activerecord/lib/active_record/associations/builder/collection_association.rb
+++ b/activerecord/lib/active_record/associations/builder/collection_association.rb
@@ -7,22 +7,11 @@ module ActiveRecord::Associations::Builder
 
     CALLBACKS = [:before_add, :after_add, :before_remove, :after_remove]
 
-    def valid_options
+    def self.valid_options(options)
       super + [:table_name, :before_add,
                :after_add, :before_remove, :after_remove, :extend]
     end
 
-    attr_reader :block_extension
-
-    def initialize(model, name, scope, options)
-      super
-      @mod = nil
-      if block_given?
-        @mod = Module.new(&Proc.new)
-        @scope = wrap_scope @scope, @mod
-      end
-    end
-
     def self.define_callbacks(model, reflection)
       super
       name    = reflection.name
@@ -32,10 +21,11 @@ module ActiveRecord::Associations::Builder
       }
     end
 
-    def define_extensions(model)
-      if @mod
+    def self.define_extensions(model, name)
+      if block_given?
         extension_module_name = "#{model.name.demodulize}#{name.to_s.camelize}AssociationExtension"
-        model.parent.const_set(extension_module_name, @mod)
+        extension = Module.new(&Proc.new)
+        model.parent.const_set(extension_module_name, extension)
       end
     end
 
@@ -78,9 +68,7 @@ module ActiveRecord::Associations::Builder
       CODE
     end
 
-    private
-
-    def wrap_scope(scope, mod)
+    def self.wrap_scope(scope, mod)
       if scope
         proc { |owner| instance_exec(owner, &scope).extending(mod) }
       else