old_contents: buster.testCase('RockstageTest', {
    setUp: function() {
      localStorage.clear();
      sessionStorage.clear();
    },
    'RS should be initialized when call script': function() {
      assert.isObject(window.RS);
      assert.isFunction(RS.put);
      assert.isFunction(RS.get);
      assert.isFunction(RS.remove);
      assert.isFunction(RS.clear);
      assert.isFunction(RS.is);
    },
    'put() should be equal storage.getItem()': function() {
      RS.put({foo: 'hoge', bar: 'fuga', baz: 'hogera'});
  
      assert.equals('hoge', JSON.parse(localStorage.getItem('foo')));
      assert.equals('fuga', JSON.parse(localStorage.getItem('bar')));
      assert.equals('hogera', JSON.parse(localStorage.getItem('baz')));
    },
    'get() should be equal storage.setItem()': function() {
      localStorage.setItem('foo', JSON.stringify('hoge'));
  
      assert.equals('hoge', RS.get('foo'));
    },
    'remove() should be clear storage': function()  {
      RS.put({foo: 'hoge', bar: 'fuga', baz: 'hogera'});
      RS.remove('foo');
  
      refute.isFalse(JSON.parse(localStorage.getItem('foo')));
    },
    'clear() sould be clear all storage': function() {
      RS.put({foo: 'hoge', bar: 'fuga', baz: 'hogera'});
      RS.clear();
  
      refute.isNull(localStorage);
    },
    'is() should be returned true in storage & should be returned false in no storage': function() {
      RS.put({foo: 'hoge', bar: 'fuga', baz: 'hogera'});
  
      assert.isTrue(RS.is('foo'));
      assert.isTrue(RS.is('bar'));
      assert.isTrue(RS.is('baz'));
      assert.isFalse(RS.is('storage'));
    },
    'length should be returned object\'s length in storage': function() {
      RS.put({foo: 'hoge', bar: 'fuga', baz: 'hogera'});
  
      assert.equals(3, RS.length);
    }
  });
  
new_contents: buster.testCase('RockstageTest', {
    setUp: function() {
      localStorage.clear();
      sessionStorage.clear();
    },
    'RS should be initialized when call script': function() {
      assert.isObject(window.RS);
      assert.isFunction(RS.put);
      assert.isFunction(RS.get);
      assert.isFunction(RS.remove);
      assert.isFunction(RS.clear);
      assert.isFunction(RS.is);
    },
    'put() should be equal storage.getItem()': function() {
      RS.put({foo: 'hoge', bar: 'fuga', baz: 'hogera'});
  
      assert.equals('hoge', JSON.parse(localStorage.getItem('foo')));
      assert.equals('fuga', JSON.parse(localStorage.getItem('bar')));
      assert.equals('hogera', JSON.parse(localStorage.getItem('baz')));
    },
    'get() should be equal storage.setItem()': function() {
      localStorage.setItem('foo', JSON.stringify('hoge'));
  
      assert.equals('hoge', RS.get('foo'));
    },
    'remove() should be clear storage': function()  {
      RS.put({foo: 'hoge', bar: 'fuga', baz: 'hogera'});
      RS.remove('foo');
  
      refute.isFalse(JSON.parse(localStorage.getItem('foo')));
    },
    'clear() sould be clear all storage': function() {
      RS.put({foo: 'hoge', bar: 'fuga', baz: 'hogera'});
      RS.clear();
  
      refute.isNull(localStorage);
    },
    'is() should be returned true in storage & should be returned false in no storage': function() {
      RS.put({foo: 'hoge', bar: 'fuga', baz: 'hogera'});
  
      assert.isTrue(RS.is('foo'));
      assert.isTrue(RS.is('bar'));
      assert.isTrue(RS.is('baz'));
      assert.isFalse(RS.is('storage'));
    },
    'length should be returned object\'s length in storage': function() {
      RS.put({foo: 'hoge', bar: 'fuga', baz: 'hogera'});
  
      assert.equals(3, RS.length());
    }
  });
  
subject: fix call length method