1 files changed, 7 insertions, 8 deletions
diff --git a/activerecord/lib/active_record/associations/builder/singular_association.rb b/activerecord/lib/active_record/associations/builder/singular_association.rb
index 6a5830e57f..e655c389a6 100644
--- a/activerecord/lib/active_record/associations/builder/singular_association.rb
+++ b/activerecord/lib/active_record/associations/builder/singular_association.rb
@@ -1,19 +1,18 @@
+# This class is inherited by the has_one and belongs_to association classes
+
 module ActiveRecord::Associations::Builder
   class SingularAssociation < Association #:nodoc:
     def valid_options
-      super + [:remote, :dependent, :counter_cache, :primary_key, :inverse_of]
-    end
-
-    def constructable?
-      true
+      super + [:remote, :dependent, :primary_key, :inverse_of]
     end
 
-    def define_accessors
+    def self.define_accessors(model, reflection)
       super
-      define_constructors if constructable?
+      define_constructors(model.generated_association_methods, reflection.name) if reflection.constructable?
     end
 
-    def define_constructors
+    # Defines the (build|create)_association methods for belongs_to or has_one association
+    def self.define_constructors(mixin, name)
       mixin.class_eval <<-CODE, __FILE__, __LINE__ + 1
         def build_#{name}(*args, &block)
           association(:#{name}).build(*args, &block)