lib/characterizable.rb in characterizable-0.0.11 vs lib/characterizable.rb in characterizable-0.0.12

@@ -7,15 +7,13 @@
   active_support/core_ext/class/attribute_accessors
   active_support/core_ext/object/blank
   active_support/core_ext/array/wrap
   active_support/core_ext/module/aliasing
   active_support/core_ext/module/delegation
-  active_support/json
 }.each do |active_support_3_requirement|
   require active_support_3_requirement
 end if ActiveSupport::VERSION::MAJOR == 3
-require 'to_json_fix'
 
 module Characterizable
   def self.included(klass)
     klass.cattr_accessor :characterizable_base
     klass.extend ClassMethods
@@ -123,19 +121,23 @@
       Blockenspiel.invoke block, characterizable_base
     end
     delegate :characteristics, :to => :characterizable_base
   end
   
+  class CharacteristicAlreadyDefined < ArgumentError
+  end
+  
   class Base
     attr_reader :klass
     def initialize(klass)
       @klass = klass
     end
     def characteristics
       @_characteristics ||= BetterHash.new
     end
     include Blockenspiel::DSL
     def has(name, options = {}, &block)
+      raise CharacteristicAlreadyDefined, "The characteristic #{name} has already been defined on #{klass}!" if characteristics.has_key?(name)
       characteristics[name] = Characteristic.new(self, name, options, &block)
       begin
         # quacks like an activemodel
         klass.define_attribute_methods if klass.respond_to?(:attribute_methods_generated?) and !klass.attribute_methods_generated?
       rescue