Merge pull request #3464 from kennyj/avoid_to_call_twice

avoided to call `Marshal.dump` twice

activesupport/lib/active_support/cache.rb

@@ -559,7 +559,7 @@ def initialize(value, options = {})
           @value = nil
         else
           @value = Marshal.dump(value)
-          if should_compress?(value, options)
+          if should_compress?(@value, options)
             @value = Zlib::Deflate.deflate(@value)
             @compressed = true
           end
@@ -613,14 +613,11 @@ def size
       end
 
       private
-        def should_compress?(value, options)
-          if options[:compress] && value
-            unless value.is_a?(Numeric)
+        def should_compress?(serialized_value, options)
+          if options[:compress]
             compress_threshold = options[:compress_threshold] || DEFAULT_COMPRESS_LIMIT
-              serialized_value = value.is_a?(String) ? value : Marshal.dump(value)
             return true if serialized_value.size >= compress_threshold
           end
-          end
           false
         end
     end