feat(source): add cache disabling for datasets (#254)

* Add cache disabling for datasets

* Invert cache disable flag

* Rename `enableCache` flag to `cache`

README.md

@@ -482,6 +482,7 @@ Datasets can be configured using the following options.
 * `debounce` – If set, will postpone the source execution until after `debounce` milliseconds
 have elapsed since the last time it was invoked.
 
+* `cache` - If set to `false`, subsequent identical queries will always execute the source function for suggestions. Defaults to `true`.
 
 ## Sources
 

src/autocomplete/dataset.js

@@ -37,6 +37,8 @@ function Dataset(o) {
 
   this.debounce = o.debounce;
 
+  this.cache = o.cache !== false;
+
   this.templates = getTemplates(o.templates, this.displayFn);
 
   this.css = _.mixin({}, css, o.appendTo ? css.appendTo : {});
@@ -235,7 +237,10 @@ _.mixin(Dataset.prototype, EventEmitter, {
   },
 
   shouldFetchFromCache: function shouldFetchFromCache(query) {
-    return this.cachedQuery === query && this.cachedSuggestions && this.cachedSuggestions.length;
+    return this.cache &&
+      this.cachedQuery === query &&
+      this.cachedSuggestions &&
+      this.cachedSuggestions.length;
   },
 
   clearCachedSuggestions: function clearCachedSuggestions() {

test/unit/dataset_spec.js

@@ -291,7 +291,7 @@ describe('Dataset', function() {
       expect(this.dataset.cachedRenderExtraArgs).toEqual([42, true, false]);
     });
 
-    it('should retrieved cached results for subsequent identical queries', function() {
+    it('should retrieve cached results for subsequent identical queries', function() {
       this.source.and.callFake(fakeGetWithSyncResults);
 
       this.dataset.update('woah');
@@ -308,6 +308,29 @@ describe('Dataset', function() {
       expect(this.dataset.getRoot()).toContainText('three');
     });
 
+    it('should not retrieve cached results for subsequent identical queries if cache is disabled', function() {
+      this.dataset = new Dataset({
+        name: 'test',
+        source: this.source = jasmine.createSpy('source'),
+        cache: false,
+      });
+
+      this.source.and.callFake(fakeGetWithSyncResultsAndExtraParams);
+
+      this.dataset.update('woah');
+      expect(this.source.calls.count()).toBe(1);
+      expect(this.dataset.getRoot()).toContainText('one');
+      expect(this.dataset.getRoot()).toContainText('two');
+      expect(this.dataset.getRoot()).toContainText('three');
+
+      this.dataset.clear();
+      this.dataset.update('woah');
+      expect(this.source.calls.count()).toBe(2);
+      expect(this.dataset.getRoot()).toContainText('one');
+      expect(this.dataset.getRoot()).toContainText('two');
+      expect(this.dataset.getRoot()).toContainText('three');
+    });
+
     it('should reuse render function extra params for subsequent identical queries', function() {
       var spy = spyOn(this.dataset, '_render');
       this.source.and.callFake(fakeGetWithSyncResultsAndExtraParams);