Fixed #4: Removing cookies are failing when the domain or path were s…

…et in the options

README.md

@@ -339,10 +339,37 @@ cookieStore.setItem('testing3', 3, {
 });
 ```
 
+**Important**: Take into account that if you want to modify or remove a cookie
+that was created with a specific `path` or `domain` / subdomain, you need to
+explicitate the domain attribute in `setItem(key, value, options)`.
+
+![cookies](https://www.dropbox.com/s/wlvgm0t8xc07me1/cookies-metadata.gif?dl=1)
+
+If you have created the cookie with **proxyStorage**, it will handle the
+metadata internally, so that you can call `removeItem(key)` safely.
+
+But if you want to modify / remove a cookie that was created from another page,
+then you should provide the metadata as `path` or `domain` in order to match
+the right cookie:
+
+```javascript
+// change the value of an external cookie in /answers
+cookieStore.setItem('landedAnswers', 999, {
+  path: '/answers',
+});
+
+// remove an external cookie in a subdomain
+cookieStore.setItem('optimizelyEndUserId', '', {
+  domain: '.healthcare.org',
+  expires: {days: -1}, // trick!
+});
+```
+
 ### Looping the storage
 
 You can loop over the items in the storage instance, e.g.
-`localStorage`, `sessionStorage`, `cookieStorage`, or `memoryStorage`.
+`localStorage`, `sessionStorage`, `cookieStorage`, or `memoryStorage`,
+but it is not a good practice, see the notes below.
 
 ```javascript
 const sessionStore = new WebStorage('sessionStorage');
@@ -361,6 +388,23 @@ for (let key in sessionStore) {
 }
 ```
 
+**Important**: Although you can loop over the storage items, it is
+recommended to use the API methods instead, this is because navigable
+items in the storage instance are not synchronized for external changes,
+e.g. a domain cookie was created from another page, or a cookie has expired.
+
+```javascript
+// not recommended, they are not synchronized
+var title = cookieStorage['title'];
+var session = cookieStorage.sessionId;
+cookieStorage['sessionId'] = 'E6URTG5';
+
+// the good way, it tracks external changes
+var title = cookieStorage.getItem('title');
+var session = cookieStorage.getItem('sessionId');
+cookieStorage.setItem('sessionId', 'E6URTG5');
+```
+
 ### Clearing data
 
 You can use the `removeItem(key)` method to delete a specific item in

dist/proxy-storage.js

@@ -253,7 +253,7 @@ function executeInterceptors(command) {
   }
   return _interceptors[command].reduce(function (val, action) {
     var transformed = action.apply(undefined, [key, val].concat(args));
-    if (transformed === undefined) return val;
+    if (transformed == null) return val;
     return transformed;
   }, value);
 }
@@ -379,7 +379,10 @@ var WebStorage = function () {
       var v = executeInterceptors('setItem', key, value, options);
       if (v !== undefined) value = v;
       this[key] = value;
-      value = JSON.stringify(value);
+      // prevents converting strings to JSON to avoid extra quotes
+      if (typeof value !== 'string') value = JSON.stringify(value);
+      // TODO: should add setTimeout for options.expires?
+      // TODO: prevent adding cookies when the domain or path are not valid?
       _proxyMechanism.proxy[this.__storage__].setItem(key, value, options);
     }
 
@@ -520,8 +523,8 @@ var $cookie = {
   },
   set: function set(value) {
     document.cookie = value;
-  }
-};
+  },
+  data: {} };
 
 /**
  * @private
@@ -536,9 +539,14 @@ var $cookie = {
 /* eslint-disable no-invalid-this */
 function buildExpirationString(date) {
   var expires = date instanceof Date ? (0, _utils.alterDate)({ date: date }) : (0, _utils.alterDate)(date);
-  return '; expires=' + expires.toUTCString();
+  return expires.toUTCString();
 }
 
+// @private
+var buildStringFor = function buildStringFor(key, data) {
+  return data[key] && '; ' + key + '=' + data[key] || '';
+};
+
 /**
  * @private
  *
@@ -564,24 +572,21 @@ function findCookie(cookie) {
 function cookieStorage() {
   var api = {
     setItem: function setItem(key, value, options) {
-      var domain = '',
-          expires = '';
       options = Object.assign({ path: '/' }, options);
+      // keep track of the metadata associated to the cookie
+      $cookie.data[key] = { path: options.path };
+      var metadata = $cookie.data[key];
       if ((0, _utils.isObject)(options.expires) || options.expires instanceof Date) {
-        expires = buildExpirationString(options.expires);
+        metadata.expires = buildExpirationString(options.expires);
       }
-      // http://stackoverflow.com/a/5671466/2247494
-      if (typeof options.domain === 'string') {
-        domain = '; domain=' + options.domain.trim();
+      if (options.domain && typeof options.domain === 'string') {
+        metadata.domain = options.domain.trim();
       }
-      var cookie = key + '=' + encodeURIComponent(value) + expires + domain + '; path=' + options.path;
-      // TODO: add metadata to store options for the cookie
-      // TODO: remove cookies are failing when domain or path were set
-      // TODO: prevent adding cookies when the domain or path are not valid
-      // TODO: remove expired cookies through getItem or setTimeout for expires
-      // console.log('before set', $cookie.get()); // eslint-disable-line
+      var expires = buildStringFor('expires', metadata);
+      var domain = buildStringFor('domain', metadata);
+      var path = buildStringFor('path', metadata);
+      var cookie = key + '=' + encodeURIComponent(value) + expires + domain + path;
       $cookie.set(cookie);
-      // console.log('after set', $cookie.get()); // eslint-disable-line
     },
     getItem: function getItem(key) {
       var value = null;
@@ -592,17 +597,20 @@ function cookieStorage() {
         value = cookie.trim().substring(nameEQ.length, cookie.length);
         value = decodeURIComponent(value);
       }
+      if (value === null) delete $cookie.data[key];
       return value;
     },
     removeItem: function removeItem(key) {
-      api.setItem(key, '', { expires: { days: -1 } });
+      var metadata = Object.assign({}, $cookie.data[key]);
+      metadata.expires = { days: -1 };
+      api.setItem(key, '', metadata);
+      delete $cookie.data[key];
     },
     clear: function clear() {
-      var eq = '=';
       var key = void 0,
-          indexEQ = void 0;
+          indexEQ = void 0; // eslint-disable-line
       $cookie.get().split(';').forEach(function (cookie) {
-        indexEQ = cookie.indexOf(eq);
+        indexEQ = cookie.indexOf('=');
         if (indexEQ > -1) {
           key = cookie.substring(0, indexEQ);
           // prevent leading spaces before the key