Inline Rails 3 templating solution

Inline Rails 3 templating solution : for ActionView RSpec testing etc. 

require 'action_view'
require 'action_view/context'

class TestERBTemplate

  ERBHandler = ActionView::Template::Handlers::ERB

  attr_accessor :output_buffer, :rendered

  def initialize
    @output_buffer = ActiveSupport::SafeBuffer.new
    @rendered = ''
  end

  def render(options = {}, local_assigns = {}, &block)
    view.assign(_assigns)
    output = view.render(options, local_assigns, &block)
    @rendered << output
    output
  end

  module Locals
    attr_accessor :locals
  end

  def locals
    @locals ||= {}
  end


  def view
    @view ||= begin                                                 
                 # lookup_context = nil, assigns_for_first_render = {}
                 view = ActionView::Base.new                                  
                   
                 # ???
                 # view.singleton_class.send :include, _helpers

                 view.extend(Locals)
                 view.locals = self.locals
                 view.output_buffer = self.output_buffer
                 view
               end
  end

  alias_method :_view, :view
  
  EXCLUDE_IVARS = %w{
    @_assertion_wrapped
    @_result
    @controller
    @layouts
    @locals
    @method_name
    @output_buffer
    @partials
    @rendered
    @request
    @routes
    @templates
    @test_passed
    @view
    @view_context_class
  }

  def _instance_variables
    instance_variables.map(&:to_s) - EXCLUDE_IVARS
  end

  def _assigns
    _instance_variables.inject({}) do |hash, var|
      name = var[1..-1].to_sym
      hash[name] = instance_variable_get(var)
      hash
    end
  end  

  def basic_template content
    @body = content
    # assert_equal "Hello", render
    puts render :inline => content
    # render(:my_local => "I'm a local")
  end

end

module MyViewHelper
  def tab_for(clazz, &block)               
    content = with_output_buffer(&block)  
    content_tag :li, content, :class => clazz
  end
end

module MyOtherViewHelper
  def hello(clazz, &block)               
    content = with_output_buffer(&block)
    content_tag :div, content, :class => clazz
  end
end


class ActionView::Base
  include MyViewHelper, MyOtherViewHelper

  def name
    'Kristian'
  end
end

test = TestERBTemplate.new # 'h'
test.basic_template "hello <%= name %>" 

test.basic_template %{
  <%= tab_for :x do %>
    <%= hello :blip do %>
      ged
    <% end %>
  <% end %>
}