Add a spec for the new plugins controller

app/assets/javascripts/admin/routes/admin-plugins.js.es6

@@ -1,6 +1,6 @@
 export default Ember.Route.extend({
   model() {
-    return Discourse.ajax("/admin/plugins.json");
+    return Discourse.ajax("/admin/plugins.json").then(res => res.plugins);
   },
 
   actions: {

app/controllers/admin/plugins_controller.rb

@@ -1,8 +1,7 @@
 class Admin::PluginsController < Admin::AdminController
 
   def index
-    # json = Discourse.plugins.map(&:metadata)
-    render_serialized(Discourse.plugins, AdminPluginSerializer)
+    render_serialized(Discourse.plugins, AdminPluginSerializer, root: 'plugins')
   end
 
 end

lib/discourse.rb

@@ -85,12 +85,11 @@ module Discourse
   end
 
   def self.disabled_plugin_names
-    return [] if @plugins.blank?
-    @plugins.select {|p| !p.enabled?}.map(&:name)
+    plugins.select {|p| !p.enabled?}.map(&:name)
   end
 
   def self.plugins
-    @plugins
+    @plugins ||= []
   end
 
   def self.assets_digest
@@ -119,12 +118,10 @@ module Discourse
 
   def self.auth_providers
     providers = []
-    if plugins
-      plugins.each do |p|
-        next unless p.auth_providers
-        p.auth_providers.each do |prov|
-          providers << prov
-        end
+    plugins.each do |p|
+      next unless p.auth_providers
+      p.auth_providers.each do |prov|
+        providers << prov
       end
     end
     providers

spec/controllers/admin/plugins_controller_spec.rb

@@ -0,0 +1,20 @@
+require 'spec_helper'
+
+describe Admin::PluginsController do
+
+  it "is a subclass of AdminController" do
+    expect(Admin::PluginsController < Admin::AdminController).to eq(true)
+  end
+
+  context "while logged in as an admin" do
+    let!(:admin) { log_in(:admin) }
+
+    it 'should return JSON' do
+      xhr :get, :index
+      response.should be_success
+      ::JSON.parse(response.body).has_key?('plugins').should == true
+    end
+  end
+
+end
+