initial work for getting testing around the filterable mixinxx

app/controllers/cards.js

@@ -1,5 +1,5 @@
 import Ember from 'ember';
-import filterableMixin from '../mixins/filterable_mixin';
+import filterableMixin from '../mixins/filterable-mixin';
 
 export default Ember.ArrayController.extend(filterableMixin, {
 

tests/unit/mixins/filterable-mixin-test.js

@@ -0,0 +1,44 @@
+import { test, moduleFor } from 'ember-qunit';
+import Ember from 'ember';
+import FilterableMixin from 'webatrice/mixins/filterable-mixin';
+
+module('FilterableMixin');
+
+var arrayController = Ember.ArrayController.extend(FilterableMixin);
+var filterProperties = [
+      Ember.Object.create({
+        propertyName: 'color',
+        values: ['red'],
+        and: false
+      })
+    ];
+
+test('it exists', function () {
+ var obj = Ember.Object.extend(FilterableMixin);
+ var subject = obj.create();
+ ok(subject);
+});
+
+test('it can filter out all blue colors', function () {
+  var subject = arrayController.create({
+    model: [{color: 'blue'},
+            {color: 'red'},
+            {color: 'blue'}],
+    filterProperties: filterProperties
+  });
+
+  equal(subject.get('arrangedContent.length'), 1);
+});
+
+test('it doesn\'t try to filters on objects that have already been filtered out', function () {
+  var subject = arrayController.create({
+    model: [{color: 'blue'}, {color: 'blue'},
+            {color: 'blue'}, {color: 'red'},
+            {color: 'red'}, {color: 'green'}],
+    filterProperties: filterProperties
+  });
+
+  equal(subject.get('arrangedContent.length'), 2);
+  subject.get('filterProperties')[0].set('values', ['red', 'green']);
+  equal(subject.get('arrangedContent.length'), 3);
+});