iterating towards a working helper

init.rb

@@ -0,0 +1,4 @@
+require 'zoomifier'
+require 'zoomifier_helper'
+
+ActionView::Base.send :include, Zoomifier::ViewHelpers

lib/zoomifier_helper.rb

@@ -1,6 +1,8 @@
 module Zoomifier
   module ViewHelpers
-    def zoomify_image_tag
+    def zoomify_image_tag(source, options = {})
+      raise ArgumentError unless options[:id]
+      "<div id=\"#{options[:id]}\"><img src=\"#{source}\" alt=\"\"/></div>"
     end
   end
 end

spec/zoomifier_helper_spec.rb

@@ -1,16 +1,22 @@
 require File.dirname(__FILE__) + '/spec_helper'
+require File.dirname(__FILE__) + '/../../../../config/environment'
 require 'zoomifier_helper'
 
-class MockActionView
+describe Zoomifier::ViewHelpers do
-  include Zoomifier::ViewHelpers
+  before(:all) do
+    ActionView::Base.send :include, Zoomifier::ViewHelpers
   end
 
-describe Zoomifier::ViewHelpers do
   before(:each) do
-    @view = MockActionView.new
+    @view = ActionView::Base.new
   end
 
   it "should respond to zoomify_image_tag" do
     @view.should respond_to(:zoomify_image_tag)
   end
+
+  it "should generate the zoomify markup" do
+    @view.zoomify_image_tag('foo.jpg', { :id => 'foo' }).should ==
+      '<div id="foo"><img src="foo.jpg" alt=""/></div>'
+  end
 end