MultiJson does not modify arguments

Related to #92

Author: rwz

lib/multi_json.rb

@@ -119,7 +119,7 @@ def load(string, options={})
   alias :decode :load
 
   def current_adapter(options={})
-    if new_adapter = options.delete(:adapter)
+    if new_adapter = options[:adapter]
       load_adapter(new_adapter)
     else
       adapter

spec/adapter_shared_example.rb

@@ -12,6 +12,12 @@
 
   it_behaves_like 'has options', lambda{ MultiJson.adapter }
 
+  it 'does not modify argument hashes' do
+    options = { :symbolize_keys => true, :pretty => false, :adapter => :json_gem }
+    expect{MultiJson.load('{}', options)}.to_not change{options}
+    expect{MultiJson.dump([42], options)}.to_not change{options}
+  end
+
   describe '.dump' do
     describe '#dump_options' do
       before{ MultiJson.dump_options = MultiJson.adapter.dump_options = {} }