json_serializer.patch

diff --git a/lib/sequel/plugins/json_serializer.rb b/lib/sequel/plugins/json_serializer.rb
index 510923dbd..1e62bdc4c 100644
--- a/lib/sequel/plugins/json_serializer.rb
+++ b/lib/sequel/plugins/json_serializer.rb
@@ -133,10 +133,8 @@ module Sequel
         end
       end
       
-      # Helper class used for making sure that cascading options
-      # for model associations works correctly.  Cascaded options
-      # work by creating instances of this class, which take a
-      # literal JSON string and have +to_json+ return it.
+      # SEQUEL6: Remove
+      # :nocov:
       class Literal
         # Store the literal JSON to use
         def initialize(json)
@@ -148,6 +146,20 @@ module Sequel
           @json
         end
       end
+      # :nocov:
+      Sequel::Deprecation.deprecate_constant(self, :Literal)
+
+      def self.as_json(obj, *v, &block)
+        if obj.is_a?(Array)
+          obj.map{|x| as_json(x, *v, &block)}
+        else
+          if obj.respond_to?(:as_json)
+            obj.as_json(*v, &block)
+          else
+            JSON.parse(Sequel.object_to_json(obj, *v, &block))
+          end
+        end
+      end
 
       module ClassMethods
         # The default opts to use when serializing model objects to JSON.
@@ -324,20 +336,7 @@ module Sequel
                 end
 
                 v = v.empty? ? [] : [v]
-
-                objs = public_send(k)
-
-                is_array = if r = model.association_reflection(k)
-                  r.returns_array?
-                else
-                  objs.is_a?(Array)
-                end
-                
-                h[key_name] = if is_array
-                  objs.map{|obj| Literal.new(Sequel.object_to_json(obj, *v))}
-                else
-                  Literal.new(Sequel.object_to_json(objs, *v))
-                end
+                h[key_name] = JsonSerializer.as_json(public_send(k), *v)
               end
             else
               Array(inc).each do |c|
@@ -347,7 +346,8 @@ module Sequel
                 else
                   key_name = c.to_s
                 end
-                h[key_name] = public_send(c)
+
+                h[key_name] = JsonSerializer.as_json(public_send(c))
               end
             end
           end
@@ -362,6 +362,14 @@ module Sequel
           h = yield h if block_given?
           Sequel.object_to_json(h, *a)
         end
+
+        def as_json(*v, &block)
+          if block
+            to_json(*v){|x| return block.call(x)}
+          else
+            to_json(*v){|x| return x}
+          end
+        end
       end
 
       module DatasetMethods
@@ -420,7 +428,7 @@ module Sequel
             else
               all
             end
-            array.map{|obj| Literal.new(Sequel.object_to_json(obj, opts, &opts[:instance_block]))}
+            JsonSerializer.as_json(array, opts, &opts[:instance_block])
           else
             all
           end