render-helper.js

var DefaultView = Ember.View.extend(Ember._Metamorph);

function controllerFor(container, templateName, context) {
  var controller = container.lookup('controller:' + templateName);

  if (!controller) {
    if (context && Ember.isArray(context)) {
      controller = Ember.ArrayController.extend({ content: context });
    } else if (context) {
      controller = Ember.ObjectController.extend({ content: context });
    } else {
      controller = Ember.Controller.extend();
    }

    container.register('controller', templateName, controller);
    controller = container.lookup('controller:' + templateName);
  }

  return controller;
}

Ember.Handlebars.registerHelper('render', function(name, context, options) {
  Ember.assert("You must pass a template to render", arguments.length >= 2);

  var container, controller, view;

  if (arguments.length === 2) {
    options = context;
    context = undefined;
  }

  if (typeof context === 'string') {
    context = Ember.Handlebars.get(options.contexts[1], context, options);
  }

  container = options.data.keywords.controller.container;

  // TODO support named views here
  view = DefaultView;

  if (controller = options.hash.controller) {
    controller = container.lookup('controller:' + controller);
    controller.set('content', context);
  } else {
    controller = controllerFor(container, name, context);
  }

  options.hash.controller = controller;
  options.hash.templateName = name;

  Ember.Handlebars.helpers.view.call(this, view, options);
});