encoding.rb in activesupport-3.1.0.beta1

- old
+ new

@@ -151,10 +151,16 @@
       instance_values
     end
   end
 end
 
+class Struct
+  def as_json(options = nil) #:nodoc:
+    Hash[members.zip(values)]
+  end
+end
+
 class TrueClass
   AS_JSON = ActiveSupport::JSON::Variable.new('true').freeze
   def as_json(options = nil) AS_JSON end #:nodoc:
 end
 
@@ -230,12 +236,11 @@
       self
     end
 
     # use encoder as a proxy to call as_json on all values in the subset, to protect from circular references
     encoder = options && options[:encoder] || ActiveSupport::JSON::Encoding::Encoder.new(options)
-    pairs = subset.map { |k, v| [k.to_s, encoder.as_json(v)] }
-    result = self.is_a?(ActiveSupport::OrderedHash) ? ActiveSupport::OrderedHash.new : Hash.new
-    pairs.inject(result) { |hash, pair| hash[pair.first] = pair.last; hash }
+    result = self.is_a?(ActiveSupport::OrderedHash) ? ActiveSupport::OrderedHash : Hash
+    result[subset.map { |k, v| [k.to_s, encoder.as_json(v)] }]
   end
 
   def encode_json(encoder)
     # values are encoded with use_options = false, because we don't want hash representations from ActiveModel to be
     # processed once again with as_json with options, as this could cause unexpected results (i.e. missing fields);