Testing apotomo widgets with RSpec

widgets.rb

module RSpec::Rails
  module WidgetExampleGroup
    extend ActiveSupport::Concern
    extend RSpec::Rails::ModuleInclusion

    include RSpec::Rails::RailsExampleGroup
    include ActionView::TestCase::Behavior
    include RSpec::Rails::ViewAssigns
    include RSpec::Rails::Matchers::RenderTemplate
    include RSpec::Rails::BrowserSimulators

    include Apotomo::WidgetShortcuts

    webrat do
      include Webrat::Matchers
    end

    module ClassMethods
      def _default_helper
        base = metadata[:example_group][:description].split('/').first
        (base.camelize + 'Helper').constantize if base
      rescue NameError
        nil
      end

      def _default_helpers
        helpers = [_default_helper].compact
        helpers << ApplicationHelper if Object.const_defined?('ApplicationHelper')
        helpers
      end
    end

    module InstanceMethods
      # :call-seq:
      #   render
      #   render(:template => "widgets/new.html.erb")
      #   render({:partial => "widgets/widget.html.erb"}, {... locals ...})
      #   render({:partial => "widgets/widget.html.erb"}, {... locals ...}) do ... end
      #
      # Delegates to ActionView::Base#render, so see documentation on that for more
      # info.
      #
      # The only addition is that you can call render with no arguments, and RSpec
      # will pass the top level description to render:
      #
      #   describe "widgets/new.html.erb" do
      #     it "shows all the widgets" do
      #       render # => view.render(:file => "widgets/new.html.erb")
      #       ...
      #     end
      #   end
      def render(options={}, local_assigns={}, &block)
        options = {:template => _default_file_to_render} if Hash === options and options.empty?
        super(options, local_assigns, &block)
      end

      # The instance of ActionView::Base that is used to render the template.
      # Use this before the +render+ call to stub any methods you want to stub
      # on the view:
      #
      #   describe "widgets/new.html.erb" do
      #     it "shows all the widgets" do
      #       view.stub(:foo) { "foo" }
      #       render
      #       ...
      #     end
      #   end
      def view
        _view
      end

      # Simulates the presence of a template on the file system by adding a
      # Rails' FixtureResolver to the front of the view_paths list. Designed to
      # help isolate view examples from partials rendered by the view template
      # that is the subject of the example.
      #
      # == Example
      #
      #   stub_template("widgets/_widget.html.erb" => "This content.")
      def stub_template(hash)
        view.view_paths.unshift(ActionView::FixtureResolver.new(hash))
      end

      # Provides access to the params hash that will be available within the
      # view:
      #
      #       params[:foo] = 'bar'
      def params
        controller.params
      end

      # Deprecated. Use +view+ instead.
      def template
        RSpec.deprecate("template","view")
        view
      end

      # Deprecated. Use +rendered+ instead.
      def response
        RSpec.deprecate("response", "rendered")
        rendered
      end

      def has_widgets_blocks
        @has_widgets
      end

      def has_widgets(&block)
        @has_widgets = block
      end

      def root
        blk = has_widgets_blocks or raise "Please setup a widget tree using TestCase.has_widgets"
        @root ||= widget("apotomo/widget", "root").tap do |root|
           self.instance_exec(root, &blk)
        end
      end

      def parent_controller
        controller
      end

      def render_widget(name, options={})
        @rendered << root.find_widget(name).tap { |w| w.opts = options }.invoke
      end

    private

      def _default_file_to_render
        example.example_group.top_level_description
      end

      def _path_parts
        _default_file_to_render.split("/")
      end

      def _controller_path
        _path_parts[0..-2].join("/")
      end

      def _inferred_action
        _path_parts.last.split(".").first
      end

      def _include_controller_helpers
        helpers = controller._helpers
        view.singleton_class.class_eval do
          include helpers unless included_modules.include?(helpers)
        end
      end
    end

    included do
      metadata[:type] = :widget
      helper *_default_helpers

      before do
        _include_controller_helpers
        controller.controller_path = _controller_path
        controller.request.path_parameters["controller"] = _controller_path
        controller.request.path_parameters["action"]     = _inferred_action unless _inferred_action =~ /^_/
      end
    end

    RSpec.configure do |c|
      c.include self, :example_group => { :file_path => /spec\/widgets/ }
    end
  end
end

This is a simple RSpec example group for Apotomo testing. The code is a merge of RSpec::Rails::ViewExampleGroup and Apotomo::TestCase. I merged only stuff I need, since I just started to learn Apotomo, so there is no event test code at the moment.