lib/characterizable.rb in characterizable-0.0.9 vs lib/characterizable.rb in characterizable-0.0.10

@@ -1,10 +1,11 @@
 require 'set'
 require 'blockenspiel'
 require 'active_support'
 require 'active_support/version'
 %w{
+  active_support/core_ext/hash/slice
   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
@@ -24,49 +25,49 @@
   
   def expire_snapshot!
     @_characteristics = nil
   end
   
-  # hashes that survive as such when you select/reject/slice them
-  # they also keep arguments passed to them
-  class SurvivorHash < Hash
-    attr_reader :survivor_args
-    def initialize(*survivor_args)
-      @survivor_args = survivor_args
-    end
-    def reject(&block)
-      inject(self.class.new(*survivor_args)) do |memo, ary|
-        unless block.call(*ary)
-          memo[ary[0]] = ary[1]
+  class BetterHash < ::Hash
+    # In Ruby 1.9, running select/reject/etc. gives you back a hash
+    if RUBY_VERSION < '1.9'
+      def reject(&block)
+        inject(Characterizable::BetterHash.new) do |memo, ary|
+          unless block.call(*ary)
+            memo[ary[0]] = ary[1]
+          end
+          memo
         end
-        memo
       end
-    end
-    def select(&block)
-      inject(self.class.new(*survivor_args)) do |memo, ary|
-        if block.call(*ary)
-          memo[ary[0]] = ary[1]
+      def select(&block)
+        inject(Characterizable::BetterHash.new) do |memo, ary|
+          if block.call(*ary)
+            memo[ary[0]] = ary[1]
+          end
+          memo
         end
-        memo
       end
-    end
-    def slice(*keep)
-      inject(self.class.new(*survivor_args)) do |memo, ary|
-        if keep.include?(ary[0])
-          memo[ary[0]] = ary[1]
+      # I need this because otherwise it will try to do self.class.new on subclasses
+      # which would get "0 for 1" arguments error with Snapshot, among other things
+      def slice(*keep)
+        inject(Characterizable::BetterHash.new) do |memo, ary|
+          if keep.include?(ary[0])
+            memo[ary[0]] = ary[1]
+          end
+          memo
         end
-        memo
       end
     end
   end
   
-  class Snapshot < SurvivorHash
-    def initialize(*survivor_args)
-      super
-      take_snapshot
+  class Snapshot < BetterHash
+    attr_reader :target
+    def initialize(target)
+      @target = target
+      _take_snapshot
     end
-    def take_snapshot
+    def _take_snapshot
       target.characterizable_base.characteristics.each do |_, c|
         if c.known?(target)
           if c.effective?(target)
             self[c.name] = c.value(target)
           elsif !c.untrumped?(target)
@@ -76,20 +77,10 @@
             lacking_keys.push c.prerequisite
           end
         end
       end
     end
-    def slice(*keep)
-      copy = self.class.new *survivor_args
-      copy.keys.each do |key|
-        copy.delete key unless keep.include? key
-      end
-      copy
-    end
-    def target
-      survivor_args.first
-    end
     def []=(key, value)
       target.expire_snapshot!
       super
     end
     def wasted_keys
@@ -130,10 +121,10 @@
     attr_reader :klass
     def initialize(klass)
       @klass = klass
     end
     def characteristics
-      @_characteristics ||= SurvivorHash.new
+      @_characteristics ||= BetterHash.new
     end
     include Blockenspiel::DSL
     def has(name, options = {}, &block)
       characteristics[name] = Characteristic.new(self, name, options, &block)
       begin