Don't cache unnamed datasets. Fixes #111.

src/dataset.js

@@ -17,13 +17,13 @@ var Dataset = (function() {
       $.error('one of local, prefetch, or remote is requried');
     }
 
-    this.name = o.name;
+    this.name = o.name || utils.getUniqueId();
     this.limit = o.limit || 5;
     this.header = o.header;
     this.footer = o.footer;
     this.template = compileTemplate(o.template, o.engine);
 
-    // used in #initialize
+    // used then deleted in #initialize
     this.local = o.local;
     this.prefetch = o.prefetch;
     this.remote = o.remote;
@@ -37,7 +37,10 @@ var Dataset = (function() {
 
     this.itemHash = {};
     this.adjacencyList = {};
-    this.storage = new PersistentStorage(o.name);
+
+    // only initialize storage if there's a name otherwise
+    // loading from storage on subsequent page loads is impossible
+    this.storage = o.name ? new PersistentStorage(o.name) : null;
   }
 
   utils.mixin(Dataset.prototype, {
@@ -52,11 +55,19 @@ var Dataset = (function() {
     _loadPrefetchData: function(o) {
       var that = this,
           deferred,
-          version = this.storage.get(this.keys.version),
-          protocol = this.storage.get(this.keys.protocol),
-          itemHash = this.storage.get(this.keys.itemHash),
-          adjacencyList = this.storage.get(this.keys.adjacencyList),
-          isExpired = version !== VERSION || protocol !== utils.getProtocol();
+          version,
+          protocol,
+          itemHash,
+          adjacencyList,
+          isExpired;
+
+      if (this.storage) {
+        version = this.storage.get(this.keys.version);
+        protocol = this.storage.get(this.keys.protocol);
+        itemHash = this.storage.get(this.keys.itemHash);
+        adjacencyList = this.storage.get(this.keys.adjacencyList);
+        isExpired = version !== VERSION || protocol !== utils.getProtocol();
+      }
 
       o = utils.isString(o) ? { url: o } : o;
       o.ttl = utils.isNumber(o.ttl) ? o.ttl : 24 * 60 * 60 * 1000;
@@ -83,12 +94,14 @@ var Dataset = (function() {
             itemHash = processedData.itemHash,
             adjacencyList = processedData.adjacencyList;
 
-        // store process data in local storage
+        // store process data in local storage, if storage is available
         // this saves us from processing the data on every page load
-        that.storage.set(that.keys.itemHash, itemHash, o.ttl);
-        that.storage.set(that.keys.adjacencyList, adjacencyList, o.ttl);
-        that.storage.set(that.keys.version, VERSION, o.ttl);
-        that.storage.set(that.keys.protocol, utils.getProtocol(), o.ttl);
+        if (that.storage) {
+          that.storage.set(that.keys.itemHash, itemHash, o.ttl);
+          that.storage.set(that.keys.adjacencyList, adjacencyList, o.ttl);
+          that.storage.set(that.keys.version, VERSION, o.ttl);
+          that.storage.set(that.keys.protocol, utils.getProtocol(), o.ttl);
+        }
 
         that._mergeProcessedData(processedData);
       }

src/typeahead.js

@@ -5,7 +5,7 @@
  */
 
 (function() {
-  var datasetCache = {}, viewKey = 'ttView', methods;
+  var cache = {}, viewKey = 'ttView', methods;
 
   methods = {
     initialize: function(datasetDefs) {
@@ -22,11 +22,13 @@
       }
 
       datasets = utils.map(datasetDefs, function(o) {
-        o.name = o.name || utils.getUniqueId();
+        var dataset = cache[o.name] ? cache[o.name] :  new Dataset(o);
 
-        return datasetCache[o.name] ?
-          datasetCache[o.name] :
-          datasetCache[o.name] = new Dataset(o);
+        if (o.name) {
+          cache[o.name] = dataset;
+        }
+
+        return dataset;
       });
 
       return this.each(initialize);

test/dataset_spec.js

@@ -55,9 +55,26 @@ describe('Dataset', function() {
   // --------------
 
   describe('#constructor', function() {
-    it('should initialize persistent storage', function() {
-      expect(new Dataset({ local: fixtureData }).storage).toBeDefined();
-      expect(PersistentStorage).toHaveBeenCalled();
+    describe('when called with a name', function() {
+    beforeEach(function() {
+      this.dataset = new Dataset({ name: '#constructor', local: fixtureData });
+    });
+
+      it('should initialize persistent storage', function() {
+        expect(this.dataset.storage).toBeDefined();
+        expect(PersistentStorage).toHaveBeenCalled();
+      });
+    });
+
+    describe('when called with no name', function() {
+      beforeEach(function() {
+        this.dataset = new Dataset({ local: fixtureData });
+      });
+
+      it('should not use persistent storage', function() {
+        expect(this.dataset.storage).toBeNull();
+        expect(PersistentStorage).not.toHaveBeenCalled();
+      });
     });
 
     describe('when called with a template but no engine', function() {
@@ -137,7 +154,11 @@ describe('Dataset', function() {
     describe('when called with prefetch', function() {
       describe('if data is available in storage', function() {
         beforeEach(function() {
-          this.dataset = new Dataset({ prefetch: '/prefetch.json' });
+          this.dataset = new Dataset({
+            name: 'prefetch',
+            prefetch: '/prefetch.json'
+          });
+
           this.dataset.storage.get.andCallFake(mockStorageFns.getHit);
           this.dataset.initialize();
         });
@@ -164,6 +185,7 @@ describe('Dataset', function() {
 
           beforeEach(function() {
             this.dataset = new Dataset({
+              name: 'prefetch',
               prefetch: {
                 url: '/prefetch.json',
                 filter: function(data) { return ['filter']; }
@@ -203,10 +225,12 @@ describe('Dataset', function() {
 
         describe('if filter was not passed in', function() {
           beforeEach(function() {
-            this.dataset = new Dataset({ prefetch: '/prefetch.json' });
+            this.dataset = new Dataset({
+              name: 'prefetch',
+              prefetch: '/prefetch.json'
+            });
 
             this.dataset.storage.get.andCallFake(mockStorageFns.getMiss);
-
             this.dataset.initialize();
 
             this.request = mostRecentAjaxRequest();