event.context is undefined

gistfile1.txt

// app_router.js
EmberTest.Router = Ember.Router.extend({
  location: 'hash',
  enableLogging: true,

  root: Ember.Route.extend({
    index: Ember.Route.extend({
      route: '/',
      redirectsTo: 'posts.index'
    }),
    posts: Ember.Route.extend({
      route: '/posts',
      // showPost: Ember.Route.transitionTo('posts.show'),
      
      eventTransitions: {
        showPost: 'posts.show'
      },
      index: Ember.Route.extend({
        route: '/',
        showPost: function(router,event){
          console.log(router);
          console.log(event);
          console.log(event.context); #is undefined
          router.transitionTo('show');
        },
        connectOutlets: function(router) {
          router.get('applicationController').connectOutlet('posts', EmberTest.Post.find());
        },
      }),
      show: Ember.Route.extend({
        route: '/:post_id',
        modelClass: EmberTest.Post,
        connectOutlets: function(router, post) {
          router.get('applicationController').connectOutlet('post', post);
        }
      }),
    })
  })
});


// post.js
EmberTest.Post = DS.Model.extend({
  title: DS.attr('string'),
  body: DS.attr('string')
});


// posts.handlebar
{{#each post in controller}}
<h1><a {{action showPost context="post" href=true}}>{{post.title}}</a></h1>
<div>{{post.body}}</div>
{{/each}}

// console log when clicking a showPost action link in /#/posts: (the three console.log outputs from the showPost action)
Class
jQuery.Event
undefined