adding by producer id filtering

app/assets/javascripts/darkswarm/filters/by_producer.js.coffee

@@ -0,0 +1,6 @@
+Darkswarm.filter "byProducer", ->
+  (objects, id) ->
+    objects ||= []
+    id ?= 0
+    objects.filter (obj)->
+      obj.producer.id == id

spec/javascripts/unit/darkswarm/filters/by_producer_spec.js.coffee

@@ -0,0 +1,21 @@
+describe 'filtering by producer', ->
+  filterByProducer = null
+  objects = [
+    {
+      producer: 
+        id: 1 
+    }
+    {
+      producer: 
+        id: 2 
+    }
+  ]
+
+  beforeEach ->
+    module 'Darkswarm'
+    inject ($filter) ->
+      filterByProducer = $filter('byProducer')
+  
+  it "filters by producer", ->
+    expect(filterByProducer(objects, 1)[0]).toBe objects[0]
+    expect(filterByProducer(objects, 2)[0]).toBe objects[1]