adding controller additions with basic behavior.

lib/cancan.rb

@@ -1,3 +1,8 @@
 $:.unshift(File.dirname(__FILE__))
-require 'cancan/ability'
 require 'cancan/instance_exec'
+require 'cancan/ability'
+require 'cancan/controller_additions'
+
+module CanCan
+  class AccessDenied < StandardError; end
+end

lib/cancan/controller_additions.rb

@@ -0,0 +1,23 @@
+module CanCan
+  module ControllerAdditions
+    def self.included(base)
+      base.helper_method :can?
+    end
+    
+    def unauthorized!
+      raise AccessDenied, "You are unable to access this page."
+    end
+    
+    def current_ability
+      ::Ability.for_user(current_user)
+    end
+    
+    def can?(*args)
+      (@current_ability ||= current_ability).can?(*args)
+    end
+  end
+end
+
+class ActionController::Base
+  include CanCan::ControllerAdditions
+end

spec/cancan/controller_additions_spec.rb

@@ -0,0 +1,32 @@
+require File.dirname(__FILE__) + '/../spec_helper'
+
+class Ability
+  include CanCan::Ability
+end
+
+describe CanCan::ControllerAdditions do
+  before(:each) do
+    @controller_class = Class.new
+    @controller = @controller_class.new
+    mock(@controller_class).helper_method(:can?)
+    @controller_class.send(:include, CanCan::ControllerAdditions)
+  end
+  
+  it "should read from the cache with request uri as key and render that text" do
+    lambda {
+      @controller.unauthorized!
+    }.should raise_error(CanCan::AccessDenied)
+  end
+  
+  it "should have a current_ability method which generates an ability for the current user" do
+    stub(@controller).current_user { :current_user }
+    @controller.current_ability.should be_kind_of(Ability)
+    @controller.current_ability.user.should == :current_user
+  end
+  
+  it "should provide a can? method which goes through the current ability" do
+    stub(@controller).current_user { :current_user }
+    @controller.current_ability.should be_kind_of(Ability)
+    @controller.can?(:foo, :bar).should be_false
+  end
+end