v0.0.3.6 - v0.5 diff

rock.diff

diff --git a/.gitignore b/.gitignore
index ca35be0..a10754b 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1 +1,2 @@
 _site
+node_modules/
diff --git a/README.md b/README.md
index f77a570..b8b975b 100644
--- a/README.md
+++ b/README.md
@@ -7,10 +7,15 @@ This library for easier using 'localStorage' & 'sessionStorage'.
 See http://layzie.github.com/rockstage_js
 
 ## General usage
+
 This script use no library yet. So add script tags in html when using it.
 
 `<script src="/your/path/rockstage.js" type="text/javascrpt" charset="utf-8"></script>`
 
+Or you want to minified file then add below.
+
+`<script src="/your/path/rockstage.min.js" type="text/javascrpt" charset="utf-8"></script>`
+
 ### Set items to storage
 
 `RS.put(object, flag)`
@@ -97,14 +102,28 @@ ex:
 RS.is('hoge', true) // Check 'hoge' in localStorage
 ```
 
+### Check length of items from storage
+
+`RS.length(flag)`
+- `flag` is flag to selecting `localStorage` or `sessionStorage`.
+
+Use this method to know the length of storage.
+
+This argument default value is `true`. This is `localStorage`. Set to `false` when using
+`sessionStorage`.
+
+ex:
+```javascript
+RS.length(true) // Return the length of localStorage.
+```
 ## Test enviroments
 
 This library tests below browsers.
 
-- Chrome 20.0.1132.47, OS X 10.7 (Lion)
-- Safari 5.1.7, OS X 10.7 (Lion)
-- Firefox 12.0, OS X 10.7 (Lion)
-- Opera 12.00, OS X 10.7 (Lion)
+- Chrome 21.0.1180.89, OS X 10.7 (Lion)
+- Safari 6.0, OS X 10.7 (Lion)
+- Firefox 15.0, OS X 10.7 (Lion)
+- Opera 12.01, OS X 10.7 (Lion)
 
 Maybe other browser can be used. But I don't test these browsers.
 
diff --git a/grunt.js b/grunt.js
new file mode 100644
index 0000000..7fc5e55
--- /dev/null
+++ b/grunt.js
@@ -0,0 +1,68 @@
+/*global module:false*/
+module.exports = function(grunt) {
+
+  // Project configuration.
+  grunt.initConfig({
+    pkg: '<json:package.json>',
+    meta: {
+      banner: '/*! <%= pkg.title || pkg.name %>.js - v<%= pkg.version %> - ' +
+        '<%= grunt.template.today("yyyy-mm-dd") %>\n' +
+        '<%= pkg.homepage ? "* " + pkg.homepage + "\n" : "" %>' +
+        '* Copyright (c) <%= grunt.template.today("yyyy") %> <%= pkg.author.name %>;' +
+        ' Licensed <%= _.pluck(pkg.licenses, "type").join(", ") %> */'
+    },
+    lint: {
+      files: ['grunt.js', 'lib/**/*.js', '*.js']
+    },
+    buster: {
+      test: {
+        config: './test/buster.js'
+      }
+    },
+    concat: {
+      dist: {
+        src: ['<banner:meta.banner>', '<file_strip_banner:lib/<%= pkg.name %>.js>'],
+        dest: '<%= pkg.name %>.js'
+      }
+    },
+    min: {
+      dist: {
+        src: ['<banner:meta.banner>', '<config:concat.dist.dest>'],
+        dest: '<%= pkg.name %>.min.js'
+      }
+    },
+    watch: {
+      files: '<config:lint.files>',
+      tasks: 'buster'
+    },
+    jshint: {
+      options: {
+        curly: true,
+        eqeqeq: true,
+        immed: true,
+        latedef: true,
+        newcap: true,
+        noarg: true,
+        sub: true,
+        undef: true,
+        boss: true,
+        eqnull: true,
+        browser: true
+      },
+      globals: {
+        browser: true,
+        devel: true
+      }
+    },
+    uglify: {}
+  });
+
+  // Default task.
+  grunt.registerTask('default', 'concat min');
+
+  // Develop task.
+  grunt.registerTask('develop', 'buster');
+
+  // load grunt-buster
+  grunt.loadNpmTasks('grunt-buster');
+};
diff --git a/lib/rockstage.js b/lib/rockstage.js
index 8c2788f..0696818 100644
--- a/lib/rockstage.js
+++ b/lib/rockstage.js
@@ -1,62 +1,23 @@
-// Copyright (c) 2012 HIRAKI Satoru, https://github.com/Layzie
-// 
-// Permission is hereby granted, free of charge, to any person obtaining
-// a copy of this software and associated documentation files (the
-// "Software"), to deal in the Software without restriction, including
-// without limitation the rights to use, copy, modify, merge, publish,
-// distribute, sublicense, and/or sell copies of the Software, and to
-// permit persons to whom the Software is furnished to do so, subject to
-// the following conditions:
-// 
-// The above copyright notice and this permission notice shall be
-// included in all copies or substantial portions of the Software.
-// 
-// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
-// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
-// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
-// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
-// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
-// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
-// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-
 /**
  * @fileOverView The library of 'localStorage' and 'sessionStorage'
  * @author HIRAKI Satoru@Layzie
- * @version 0.0.3.6
+ * @version 0.0.5
  */
 
 (function(window, undefined) {
   'use strict';
-
   /**
-   * This function is called when 'RS' will be loaded. Then check the storageprivate
-   * and set 'RS' name space in 'window'. (This is private)
+   * This function check the type. (This is private)
    * @private
-   * @return {Void} Return nothing
+   * @param {String} type String which you want to check type.
+   * @param argument Any type want to compare to type.
+   * @return {Boolean} Return type and argument is equal then return true.
    */
-  (function _init() {
-    if (window.localStorage && window.sessionStorage) {
-      if (_checkArgument('Undefined', window.RS)) {
-        window.RS = {};
-      }
+  function _checkArgument(type, argument) {
+    var object = Object.prototype.toString.call(argument).slice(8, -1);
 
-      /**
-       * @namespace RS This library's namespace is 'RS'
-       */
-      window.RS = {
-        put: put,
-        get: get,
-        remove: remove,
-        clear: clear,
-        is: is
-      };
-    } else {
-      /**
-       * @throws {Error} If a browser have no storage.
-       */
-      throw new Error('RS: This browser have no storage.');
-    }
-  })();
+    return argument !== undefined && argument !== null && object === type;
+  }
 
   /**
    * This function is select the storage. True or undefined is
@@ -67,32 +28,22 @@
    * @return {Object} Return localStorage or sessionStorage.
    */
   function _selectStorage(flag, fun) {
-    var storage;
+    var order = (fun !== 'clear()') ? '2nd ' : '',
+        storage;
 
     if (_checkArgument('Boolean', flag) || flag === undefined) {
-      return storage = (flag === true || flag === undefined) ? localStorage : sessionStorage;
+      storage = (flag === true || flag === undefined) ? localStorage : sessionStorage;
+
+      return storage;
     } else {
       /**
-       * @throws {Error} If second argument isn't boolean.
+       * @throws {Error} If second argument(only argyment in RS.clear()) isn't boolean.
        */
-      throw new Error('RS.' + fun + ': 2nd argument should be boolean');
+      throw new Error('RS.' + fun + ': ' + order + 'argument should be boolean');
     }
   }
 
   /**
-   * This function check the type. (This is private)
-   * @private
-   * @param {String} type String which you want to check type.
-   * @param argument Any type want to compare to type.
-   * @return {Boolean} Return type and argument is equal then return true.
-   */
-  function _checkArgument(type, argument) {
-    var object = Object.prototype.toString.call(argument).slice(8, -1);
-
-    return argument !== undefined && argument !== null && object === type;
-  }
-
-  /**
    * You can set object into the storage.
    * @param {Object} obj Object which you want to save the storage.
    * @param {Boolean} flag Boolean which the storage you want to use. Default is 'true'.
@@ -202,5 +153,49 @@
       throw new Error('RS.is(): 1st argument should be strings');
     }
   }
-})(this);
+
+  /**
+   * You can check existance of a object in the storage.
+   * @param {Boolean} flag Boolean which the storage you want to use. Default is 'true'.
+   * @return {Number} Return object's length in storage
+   * @example When you'll check object's length in localStorage.
+   * RS.length();
+   */
+  function length(flag) {
+    var storage = _selectStorage(flag, 'length()');
+
+    return storage.length;
+  }
+
+  /**
+   * This function is called when 'RS' will be loaded. Then check the storageprivate
+   * and set 'RS' name space in 'window'. (This is private)
+   * @private
+   * @return {Void} Return nothing
+   */
+  (function _init() {
+    if (window.localStorage && window.sessionStorage) {
+      if (_checkArgument('Undefined', window.RS)) {
+        window.RS = {};
+      }
+
+      /**
+       * @namespace RS This library's namespace is 'RS'
+       */
+      window.RS = {
+        put: put,
+        get: get,
+        remove: remove,
+        clear: clear,
+        is: is,
+        length: length
+      };
+    } else {
+      /**
+       * @throws {Error} If a browser have no storage.
+       */
+      throw new Error('RS: This browser have no storage.');
+    }
+  }());
+}(this));
 
diff --git a/makefile b/makefile
deleted file mode 100644
index d8fb80f..0000000
--- a/makefile
+++ /dev/null
@@ -1,10 +0,0 @@
-all: compress
-
-compress:
-	uglifyjs --output ./rockstage.min.js lib/rockstage.js; cp lib/rockstage.js ./rockstage.js
-
-clean:
-	rm ./rockstage.js ./rockstage.min.js
-
-.PHONY: Rockstage.js is compressed.
-
diff --git a/package.json b/package.json
index 35a7768..1b92439 100644
--- a/package.json
+++ b/package.json
@@ -1,15 +1,44 @@
 {
-  "author" : "Layzie",
-  "name" : "rockstage.js",
-  "description" : "The JavaScript library for using 'localStorage' & 'sessionStorage' more easy",
-  "version" : "0.0.3.6",
-  "scripts" : {
-    "test" : "node_modules/.bin/buster-test"
-  },
-  "dependencies" : {
-    "buster" : "~0.6"
-  },
-  "engines" : {
-    "node" : "~0.8"
-  }
+  "author": {
+    "name": "HIRAKI Satoru",
+    "email": "[email protected]",
+    "url": "http://layzie.hatenablog.com/"
+  },
+  "name": "rockstage",
+  "description": "The JavaScript library for using 'localStorage' & 'sessionStorage' more easy",
+  "version" : "0.0.5",
+  "scripts": {
+    "test": "node_modules/.bin/buster-test"
+  },
+  "dependencies": {
+    "buster": "~0.6.3"
+  },
+  "devDependencies": {
+    "buster": "~0.6.3",
+    "grunt": "~0.3.17",
+    "grunt-buster": "~0.1.2"
+  },
+  "engines": {
+    "node": "~0.8"
+  },
+  "main": "./lib/rockstage.js",
+  "directories": {
+    "test": "test"
+  },
+  "repository": {
+    "type": "git",
+    "url": "git://github.com/Layzie/rockstage_js.git"
+  },
+  "keywords": [
+    "Localstorage",
+    "html5",
+    "javascript"
+  ],
+  "homepage": "http://layzie.github.com/rockstage_js",
+  "licenses": [
+    {
+      "type": "MIT",
+      "url": "https://github.com/Layzie/rockstage_js/blob/master/LICENCE"
+    }
+  ]
 }
diff --git a/rockstage.js b/rockstage.js
index 8c2788f..ce08a85 100644
--- a/rockstage.js
+++ b/rockstage.js
@@ -1,62 +1,21 @@
-// Copyright (c) 2012 HIRAKI Satoru, https://github.com/Layzie
-// 
-// Permission is hereby granted, free of charge, to any person obtaining
-// a copy of this software and associated documentation files (the
-// "Software"), to deal in the Software without restriction, including
-// without limitation the rights to use, copy, modify, merge, publish,
-// distribute, sublicense, and/or sell copies of the Software, and to
-// permit persons to whom the Software is furnished to do so, subject to
-// the following conditions:
-// 
-// The above copyright notice and this permission notice shall be
-// included in all copies or substantial portions of the Software.
-// 
-// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
-// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
-// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
-// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
-// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
-// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
-// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-
-/**
- * @fileOverView The library of 'localStorage' and 'sessionStorage'
- * @author HIRAKI Satoru@Layzie
- * @version 0.0.3.6
- */
+/*! rockstage.js - v0.0.5 - 2012-12-14
+* http://layzie.github.com/rockstage_js
+* Copyright (c) 2012 HIRAKI Satoru; Licensed MIT */
 
 (function(window, undefined) {
   'use strict';
-
   /**
-   * This function is called when 'RS' will be loaded. Then check the storageprivate
-   * and set 'RS' name space in 'window'. (This is private)
+   * This function check the type. (This is private)
    * @private
-   * @return {Void} Return nothing
+   * @param {String} type String which you want to check type.
+   * @param argument Any type want to compare to type.
+   * @return {Boolean} Return type and argument is equal then return true.
    */
-  (function _init() {
-    if (window.localStorage && window.sessionStorage) {
-      if (_checkArgument('Undefined', window.RS)) {
-        window.RS = {};
-      }
+  function _checkArgument(type, argument) {
+    var object = Object.prototype.toString.call(argument).slice(8, -1);
 
-      /**
-       * @namespace RS This library's namespace is 'RS'
-       */
-      window.RS = {
-        put: put,
-        get: get,
-        remove: remove,
-        clear: clear,
-        is: is
-      };
-    } else {
-      /**
-       * @throws {Error} If a browser have no storage.
-       */
-      throw new Error('RS: This browser have no storage.');
-    }
-  })();
+    return argument !== undefined && argument !== null && object === type;
+  }
 
   /**
    * This function is select the storage. True or undefined is
@@ -67,32 +26,22 @@
    * @return {Object} Return localStorage or sessionStorage.
    */
   function _selectStorage(flag, fun) {
-    var storage;
+    var order = (fun !== 'clear()') ? '2nd ' : '',
+        storage;
 
     if (_checkArgument('Boolean', flag) || flag === undefined) {
-      return storage = (flag === true || flag === undefined) ? localStorage : sessionStorage;
+      storage = (flag === true || flag === undefined) ? localStorage : sessionStorage;
+
+      return storage;
     } else {
       /**
-       * @throws {Error} If second argument isn't boolean.
+       * @throws {Error} If second argument(only argyment in RS.clear()) isn't boolean.
        */
-      throw new Error('RS.' + fun + ': 2nd argument should be boolean');
+      throw new Error('RS.' + fun + ': ' + order + 'argument should be boolean');
     }
   }
 
   /**
-   * This function check the type. (This is private)
-   * @private
-   * @param {String} type String which you want to check type.
-   * @param argument Any type want to compare to type.
-   * @return {Boolean} Return type and argument is equal then return true.
-   */
-  function _checkArgument(type, argument) {
-    var object = Object.prototype.toString.call(argument).slice(8, -1);
-
-    return argument !== undefined && argument !== null && object === type;
-  }
-
-  /**
    * You can set object into the storage.
    * @param {Object} obj Object which you want to save the storage.
    * @param {Boolean} flag Boolean which the storage you want to use. Default is 'true'.
@@ -202,5 +151,49 @@
       throw new Error('RS.is(): 1st argument should be strings');
     }
   }
-})(this);
+
+  /**
+   * You can check existance of a object in the storage.
+   * @param {Boolean} flag Boolean which the storage you want to use. Default is 'true'.
+   * @return {Number} Return object's length in storage
+   * @example When you'll check object's length in localStorage.
+   * RS.length();
+   */
+  function length(flag) {
+    var storage = _selectStorage(flag, 'length()');
+
+    return storage.length;
+  }
+
+  /**
+   * This function is called when 'RS' will be loaded. Then check the storageprivate
+   * and set 'RS' name space in 'window'. (This is private)
+   * @private
+   * @return {Void} Return nothing
+   */
+  (function _init() {
+    if (window.localStorage && window.sessionStorage) {
+      if (_checkArgument('Undefined', window.RS)) {
+        window.RS = {};
+      }
+
+      /**
+       * @namespace RS This library's namespace is 'RS'
+       */
+      window.RS = {
+        put: put,
+        get: get,
+        remove: remove,
+        clear: clear,
+        is: is,
+        length: length
+      };
+    } else {
+      /**
+       * @throws {Error} If a browser have no storage.
+       */
+      throw new Error('RS: This browser have no storage.');
+    }
+  }());
+}(this));
 
diff --git a/rockstage.min.js b/rockstage.min.js
index 9ea35e6..6e2d731 100644
--- a/rockstage.min.js
+++ b/rockstage.min.js
@@ -1,25 +1,4 @@
-// Copyright (c) 2012 HIRAKI Satoru, https://github.com/Layzie
-// 
-// Permission is hereby granted, free of charge, to any person obtaining
-// a copy of this software and associated documentation files (the
-// "Software"), to deal in the Software without restriction, including
-// without limitation the rights to use, copy, modify, merge, publish,
-// distribute, sublicense, and/or sell copies of the Software, and to
-// permit persons to whom the Software is furnished to do so, subject to
-// the following conditions:
-// 
-// The above copyright notice and this permission notice shall be
-// included in all copies or substantial portions of the Software.
-// 
-// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
-// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
-// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
-// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
-// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
-// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
-// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-/**
- * @fileOverView The library of 'localStorage' and 'sessionStorage'
- * @author HIRAKI Satoru@Layzie
- * @version 0.0.3.6
- */(function(e,t){"use strict";function n(e,n){var i;if(r("Boolean",e)||e===t)return i=e===!0||e===t?localStorage:sessionStorage;throw new Error("RS."+n+": 2nd argument should be boolean")}function r(e,n){var r=Object.prototype.toString.call(n).slice(8,-1);return n!==t&&n!==null&&r===e}function i(e,t){var i=n(t,"put()");if(!r("Object",e)||!!r("Array",e))throw new Error("RS.put(): 1st argument should be object");for(var s in e)e.hasOwnProperty(s)&&i.setItem(s,JSON.stringify(e[s]))}function s(e,t){var i=n(t,"get()"),s=i.getItem(e);if(r("String",e))return s?JSON.parse(s):console.log("RS.get(): This key is not in storage");throw new Error("RS.get(): 1st argument should be string")}function o(e,t){var i=n(t,"remove()"),s=i.getItem(e);r("String",e)&&(s?i.removeItem(e):console.log("RS.remove(): This key is not in storage"))}function u(e){var t=n(e,"clear()");t.clear()}function a(e,t){var i=n(t,"is()"),s=i.getItem(e);if(r("String",e))return s?!0:!1;throw new Error("RS.is(): 1st argument should be strings")}(function(){if(!e.localStorage||!e.sessionStorage)throw new Error("RS: This browser have no storage.");r("Undefined",e.RS)&&(e.RS={}),e.RS={put:i,get:s,remove:o,clear:u,is:a}})()})(this);
\ No newline at end of file
+/*! rockstage.js - v0.0.5 - 2012-12-14
+* http://layzie.github.com/rockstage_js
+* Copyright (c) 2012 HIRAKI Satoru; Licensed MIT */
+(function(e,t){"use strict";function n(e,n){var r=Object.prototype.toString.call(n).slice(8,-1);return n!==t&&n!==null&&r===e}function r(e,r){var i=r!=="clear()"?"2nd ":"",s;if(n("Boolean",e)||e===t)return s=e===!0||e===t?localStorage:sessionStorage,s;throw new Error("RS."+r+": "+i+"argument should be boolean")}function i(e,t){var i=r(t,"put()");if(!n("Object",e)||!!n("Array",e))throw new Error("RS.put(): 1st argument should be object");for(var s in e)e.hasOwnProperty(s)&&i.setItem(s,JSON.stringify(e[s]))}function s(e,t){var i=r(t,"get()"),s=i.getItem(e);if(n("String",e))return s?JSON.parse(s):console.log("RS.get(): This key is not in storage");throw new Error("RS.get(): 1st argument should be string")}function o(e,t){var i=r(t,"remove()"),s=i.getItem(e);n("String",e)&&(s?i.removeItem(e):console.log("RS.remove(): This key is not in storage"))}function u(e){var t=r(e,"clear()");t.clear()}function a(e,t){var i=r(t,"is()"),s=i.getItem(e);if(n("String",e))return s?!0:!1;throw new Error("RS.is(): 1st argument should be strings")}function f(e){var t=r(e,"length()");return t.length}(function(){if(!e.localStorage||!e.sessionStorage)throw new Error("RS: This browser have no storage.");n("Undefined",e.RS)&&(e.RS={}),e.RS={put:i,get:s,remove:o,clear:u,is:a,length:f}})()})(this);
\ No newline at end of file
diff --git a/test/buster.js b/test/buster.js
index c9ff24d..ba5e21f 100644
--- a/test/buster.js
+++ b/test/buster.js
@@ -3,6 +3,6 @@ var config = module.exports;
 config['RockstageTest'] = {
   env: 'browser',
   rootPath: '../',
-  src: ['lib/rockstage.js', 'rockstage.min.js'],
+  src: ['lib/rockstage.js'],
   tests: ['test/*-test.js']
 };
diff --git a/test/rockstage-exception-test.js b/test/rockstage-exception-test.js
index 6077934..89c480a 100644
--- a/test/rockstage-exception-test.js
+++ b/test/rockstage-exception-test.js
@@ -25,7 +25,7 @@ buster.testCase('RockstageExceptionTest', {
     try {
       RS.clear(function() {});
     } catch(e) {
-      assert.same(e.message, 'RS.clear(): 2nd argument should be boolean');
+      assert.same(e.message, 'RS.clear(): argument should be boolean');
     }
   },
   'RS should be called when browser have storage': function() {
diff --git a/test/rockstage-storage-test.js b/test/rockstage-storage-test.js
index 4edba0c..4f85563 100644
--- a/test/rockstage-storage-test.js
+++ b/test/rockstage-storage-test.js
@@ -30,7 +30,7 @@ buster.testCase('RockstageStorageTest', {
     refute.equals(null, RS.remove('bar', true));
     refute.equals(null, RS.remove('bar'));
   },
-  'RS.clear() should be chosen localStorage by 2nd argument is true or undefined': function() {
+  'RS.clear() should be chosen localStorage by argument is true or undefined': function() {
     var lStorage = localStorage.setItem('foo', JSON.stringify('hoge'));
     var sStorage = sessionStorage.setItem('bar', JSON.stringify('fuga'));
 
@@ -68,7 +68,7 @@ buster.testCase('RockstageStorageTest', {
     assert.equals(undefined, RS.remove('bar', false));
     refute.equals(null, RS.remove('foo', false));
   },
-  'RS.clear() should be chosen localStorage by 2nd argument is true or undefined': function() {
+  'RS.clear() should be chosen localStorage by argument is true or undefined': function() {
     var lStorage = localStorage.setItem('foo', JSON.stringify('hoge'));
     var sStorage = sessionStorage.setItem('bar', JSON.stringify('fuga'));
 
diff --git a/test/rockstage-test.js b/test/rockstage-test.js
index 90d3712..18e47c8 100644
--- a/test/rockstage-test.js
+++ b/test/rockstage-test.js
@@ -42,5 +42,10 @@ buster.testCase('RockstageTest', {
     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());
   }
 });