Add initial support for Oj

TODO: Fix failing specs: https://gist.github.com/089bb90e8da1ad65f6c2

Author: sferik

Gemfile

@@ -1,6 +1,7 @@
 source 'https://rubygems.org'
 
 gem 'json',      '~> 1.4', :require => nil
+gem 'oj',        '~> 1.0', :require => nil
 gem 'yajl-ruby', '~> 1.0', :require => nil
 
 gemspec

lib/multi_json.rb

@@ -20,6 +20,7 @@ def engine
   end
 
   REQUIREMENT_MAP = [
+    ["oj", :oj],
     ["yajl", :yajl],
     ["json", :json_gem],
     ["json/pure", :json_pure]
@@ -32,6 +33,7 @@ def engine
   # if any engines are already loaded, then checks
   # to see which are installed if none are loaded.
   def default_engine
+    return :oj if defined?(::Oj)
     return :yajl if defined?(::Yajl)
     return :json_gem if defined?(::JSON)
 

lib/multi_json/engines/oj.rb

@@ -0,0 +1,18 @@
+require 'oj' unless defined?(Oj)
+
+module MultiJson
+  module Engines
+    # Use the Oj library to encode/decode.
+    class Oj
+      ParseError = SyntaxError
+
+      def self.decode(string, options = {}) #:nodoc:
+        ::Oj.load(string, options)
+      end
+
+      def self.encode(object, options = {}) #:nodoc:
+        ::Oj.dump(object, options)
+      end
+    end
+  end
+end

spec/helper.rb

@@ -25,10 +25,6 @@ def to_json(options = {})
   end
 end
 
-def yajl_on_travis(engine)
-  ENV['TRAVIS'] && engine == 'yajl' && jruby?
-end
-
 def nsjsonserialization_on_other_than_macruby(engine)
   engine == 'nsjsonserialization' && !macruby?
 end

spec/multi_json_spec.rb

@@ -9,11 +9,13 @@
     context 'when no other json implementations are available' do
       before do
         @old_map = MultiJson::REQUIREMENT_MAP
+        @old_oj = Object.const_get :Oj if Object.const_defined?(:Oj)
         @old_yajl = Object.const_get :Yajl if Object.const_defined?(:Yajl)
         @old_json = Object.const_get :JSON if Object.const_defined?(:JSON)
         MultiJson::REQUIREMENT_MAP.each_with_index do |(library, engine), index|
           MultiJson::REQUIREMENT_MAP[index] = ["foo/#{library}", engine]
         end
+        Object.send :remove_const, :Oj if @old_oj
         Object.send :remove_const, :Yajl if @old_yajl
         Object.send :remove_const, :JSON if @old_json
       end
@@ -22,6 +24,7 @@
         @old_map.each_with_index do |(library, engine), index|
           MultiJson::REQUIREMENT_MAP[index] = [library, engine]
         end
+        Object.const_set :Oj, @old_oj if @old_oj
         Object.const_set :Yajl, @old_yajl if @old_yajl
         Object.const_set :JSON, @old_json if @old_json
       end
@@ -38,8 +41,8 @@
 
     it 'defaults to the best available gem' do
       unless jruby?
-        require 'yajl'
-        MultiJson.engine.name.should == 'MultiJson::Engines::Yajl'
+        require 'oj'
+        MultiJson.engine.name.should == 'MultiJson::Engines::Oj'
       else
         require 'json'
         MultiJson.engine.name.should == 'MultiJson::Engines::JsonGem'
@@ -57,11 +60,7 @@
     end
   end
 
-  %w(json_gem json_pure ok_json yajl nsjsonserialization).each do |engine|
-    if yajl_on_travis(engine)
-      puts "Yajl with JRuby is not tested on Travis as C-exts are turned off due to there experimental nature"
-      next
-    end
+  %w(json_gem json_pure nsjsonserialization oj ok_json yajl).each do |engine|
     if nsjsonserialization_on_other_than_macruby(engine)
       puts "NSJSONSerialization is exclusively available for MacRuby only."
       next