releasing version 1.3.4

Conflicts:
	lib/cancan/ability.rb
	lib/cancan/active_record_additions.rb
	lib/cancan/can_definition.rb
	spec/cancan/ability_spec.rb

CHANGELOG.rdoc

@@ -1,3 +1,146 @@
-*0.1.0* (Nov 16th, 2009)
+1.3.4 (August 31, 2010)
+
+* Don't stop at +cannot+ with hash conditions when checking class (thanks tamoya) - see issue #131
+
+
+1.3.3 (August 20, 2010)
+
+* Switching to Rspec namespace to remove deprecation warning in Rspec 2 - see issue #119
+
+* Pluralize nested associations for conditions in accessible_by (thanks mlooney) - see issue #123
+
+
+1.3.2 (August 7, 2010)
+
+* Fixing slice error when passing in custom resource name - see issue #112
+
+
+1.3.1 (August 6, 2010)
+
+* Fixing protected sanitize_sql error - see issue #111
+
+
+1.3.0 (August 6, 2010)
+
+* Adding :find_by option to load_resource - see issue #19
+
+* Adding :singleton option to load_resource - see issue #93
+
+* Supporting multiple resources in :through option for polymorphic associations - see issue #73
+
+* Supporting Single Table Inheritance for "can" comparisons - see issue #55
+
+* Adding :instance_name option to load/authorize_resource - see issue #44
+
+* Don't pass nil to "new" to keep MongoMapper happy - see issue #63
+
+* Parent resources are now authorized with :read action.
+
+* Changing :resource option in load/authorize_resource back to :class with ability to pass false
+
+* Removing :nested option in favor of :through option with separate load/authorize call
+
+* Moving internal logic from ResourceAuthorization to ControllerResource class
+
+* Supporting multiple "can" and "cannot" calls with accessible_by (thanks funny-falcon) - see issue #71
+
+* Supporting deeply nested aliases - see issue #98
+
+
+1.2.0 (July 16, 2010)
+
+* Load nested parent resources on collection actions such as "index" (thanks dohzya)
+
+* Adding :name option to load_and_authorize_resource if it does not match controller - see issue #65
+
+* Fixing issue when using accessible_by with nil can conditions (thanks jrallison) - see issue #66
+
+* Pluralize table name for belongs_to associations in can conditions hash (thanks logandk) - see issue #62
+
+* Support has_many association or arrays in can conditions hash
+
+* Adding joins clause to accessible_by when conditions are across associations
+
+
+1.1.1 (April 17, 2010)
+
+* Fixing behavior in Rails 3 by properly initializing ResourceAuthorization
+
+
+1.1.0 (April 17, 2010)
+
+* Supporting arrays, ranges, and nested hashes in ability conditions
+
+* Removing "unauthorized!" method in favor of "authorize!" in controllers
+
+* Adding action, subject and default_message abilities to AccessDenied exception - see issue #40
+
+* Adding caching to current_ability controller method, if you're overriding this be sure to add caching too.
+
+* Adding "accessible_by" method to Active Record for fetching records matching a specific ability
+
+* Adding conditions behavior to Ability#can and fetch with Ability#conditions - see issue #53
+
+* Renaming :class option to :resource for load_and_authorize_resource which now supports a symbol for non models - see issue #45
+
+* Properly handle Admin::AbilitiesController in params[:controller] - see issue #46
+
+* Adding be_able_to RSpec matcher (thanks dchelimsky), requires Ruby 1.8.7 or higher - see issue #54
+
+* Support additional arguments to can? which get passed to the block - see issue #48
+
+
+1.0.2 (Dec 30, 2009)
+
+* Adding clear_aliased_actions to Ability which removes previously defined actions including defaults - see issue #20
+
+* Append aliased actions (don't overwrite them) - see issue #20
+
+* Adding custom message argument to unauthorized! method (thanks tjwallace) - see issue #18
+
+
+1.0.1 (Dec 14, 2009)
+
+* Adding :class option to load_resource so one can customize which class to use for the model - see issue #17
+
+* Don't fetch parent of nested resource if *_id parameter is missing so it works with shallow nested routes - see issue #14
+
+
+1.0.0 (Dec 13, 2009)
+
+* Don't set resource instance variable if it has been set already - see issue #13
+
+* Allowing :nested option to accept an array for deep nesting
+
+* Adding :nested option to load resource method - see issue #10
+
+* Pass :only and :except options to before filters for load/authorize resource methods.
+
+* Adding :collection and :new options to load_resource method so we can specify behavior of additional actions if needed.
+
+* BACKWARDS INCOMPATIBLE: turning load and authorize resource methods into class methods which set up the before filter so they can accept additional arguments.
+
+
+0.2.1 (Nov 26, 2009)
+
+* many internal refactorings - see issues #11 and #12
+
+* adding "cannot" method to define which abilities cannot be done - see issue #7
+
+* support custom objects (usually symbols) in can definition - see issue #8
+
+
+0.2.0 (Nov 17, 2009)
+
+* fix behavior of load_and_authorize_resource for namespaced controllers - see issue #3
+
+* support arrays being passed to "can" to specify multiple actions or classes - see issue #2
+
+* adding "cannot?" method to ability, controller, and view which is inverse of "can?" - see issue #1
+
+* BACKWARDS INCOMPATIBLE: use Ability#initialize instead of 'prepare' to set up abilities - see issue #4
+
+
+0.1.0 (Nov 16, 2009)
 
 * initial release

README.rdoc

@@ -1,33 +1,35 @@
 = CanCan
 
-This is a simple authorization solution for Rails which is completely decoupled from how you set up the user's roles. All permissions are stored in a single location for convenience.
+Wiki[http://wiki.github.com/ryanb/cancan] | RDocs[http://rdoc.info/projects/ryanb/cancan] | Screencast[http://railscasts.com/episodes/192-authorization-with-cancan]
 
-This assumes you already have an authentication solution (such as Authlogic) which proves a current_user model.
+CanCan is an authorization solution for Ruby on Rails for restricting what a given user is allowed to access throughout the application. It does not care how your user roles are defined, it simply focusses on keeping permission logic in a single location (the +Ability+ class) so it is not duplicated across controllers, views, and database queries.
+
+By default, the +current_user+ method is required, so if you have not already, set up some authentication (such as Authlogic[http://github.com/binarylogic/authlogic] or Devise[http://github.com/plataformatec/devise]). See {Changing Defaults}[http://wiki.github.com/ryanb/cancan/changing-defaults] if you need different behavior.
 
 
 == Installation
 
-You can set it up as a gem in your environment.rb file.
+To install CanCan, include the gem in the environment.rb in Rails 2.3.
 
-  config.gem "cancan", :source => "http://gemcutter.org"
+  config.gem "cancan"
 
-And then install the gem.
+Or the Gemfile in Rails 3.
 
-  gem install cancan
+  gem "cancan"
 
-Alternatively you can install it as a Rails plugin.
+Alternatively it can be installed as a plugin.
 
   script/plugin install git://github.com/ryanb/cancan.git
 
 
-== Setup
+== Getting Started
 
-First define a class called Ability, place it in "models/ability.rb".
+First, define a class called +Ability+ in "models/ability.rb" or anywhere else in the load path. It should look something like this.
 
   class Ability
     include CanCan::Ability
 
-    def prepare(user)
+    def initialize(user)
       if user.admin?
         can :manage, :all
       else
@@ -36,158 +38,115 @@ First define a class called Ability, place it in "models/ability.rb".
     end
   end
 
-This class is where all permissions will go. See the "Defining Abilities" section below for more information.
+This is where all permissions will go. See the "Defining Abilities" section below for more information.
 
-In the view layer you can access the current permissions at any point using the "can?" method. See "Checking Abilities" section below.
+The current user's permissions can be accessed using the "can?" and "cannot?" methods in the view and controller.
 
   <% if can? :update, @article %>
     <%= link_to "Edit", edit_article_path(@article) %>
   <% end %>
 
-You can also use this method in the controller layer along with the "unauthorized!" method to restrict access.
+See {Checking Abilities}[http://wiki.github.com/ryanb/cancan/checking-abilities] for more information
+
+The "authorize!" method in the controller will raise an exception if the user is not able to perform the given action.
 
   def show
     @article = Article.find(params[:id])
-    unauthorized! unless can? :read, @article
+    authorize! :read, @article
   end
 
-Setting this for every action can be tedious, therefore a before filter is also provided for automatically applying this setting to a RESTful style resource controller.
+Setting this for every action can be tedious, therefore the +load_and_authorize_resource+ method is provided to automatically authorize all actions in a RESTful style resource controller. It will use a before filter to load the resource into an instance variable and authorize it for each action.
 
   class ArticlesController < ApplicationController
-    before_filter :load_and_authorize_resource
+    load_and_authorize_resource
 
     def show
-      # @article is already loaded
+      # @article is already loaded and authorized
     end
   end
 
-If the user authorization fails, a CanCan::AccessDenied exception will be raised. You can catch this and modify its behavior.
+See {Authorizing Controller Actions}[http://wiki.github.com/ryanb/cancan/authorizing-controller-actions] for more information
+
+If the user authorization fails, a CanCan::AccessDenied exception will be raised. You can catch this and modify its behavior in the +ApplicationController+.
 
   class ApplicationController < ActionController::Base
-    rescue_from CanCan::AccessDenied, :with => :access_denied
+    rescue_from CanCan::AccessDenied do |exception|
-  
+      flash[:error] = exception.message
-    protected
-  
-    def access_denied
-      flash[:error] = "Sorry, you are not allowed to access that page."
       redirect_to root_url
     end
   end
 
+See {Exception Handling}[http://wiki.github.com/ryanb/cancan/exception-handling] for more information.
+
 
 == Defining Abilities
 
-As shown above, the Ability#prepare method is where all user permissions are defined. The user model is passed into this method so you are free to modify the permissions based on the user's attributes. This way CanCan is completely decoupled with how you choose to handle roles.
+As shown above, the +Ability+ class is where all user permissions are defined. The user model is passed into the initialize method so the permissions can be modified based on any user attributes. CanCan makes no assumptions about how roles are handled in your application. See {Role Based Authorization}[http://wiki.github.com/ryanb/cancan/role-based-authorization] for an example.
 
-The "can" method accepts two arguments, the first one is the action you're setting the permission for, the second one is the class of object you're setting it on.
+The +can+ method is used to define permissions and requires two arguments. The first one is the action you're setting the permission for, the second one is the class of object you're setting it on.
 
   can :update, Article
 
-You can pass an array for either of these parameters to match any one.
+You can pass an array for either of these parameters to match any one. In this case the user will have the ability to update or destroy both articles and comments.
 
   can [:update, :destroy], [Article, Comment]
 
-In this case the user has the ability to update or destroy both articles and comments.
+Use :+manage+ to represent any action and :+all+ to represent any class. Here are some examples.
 
-You can pass a block to provide logic based on the article's attributes. For example:
+  can :manage, Article   # has permissions to do anything to articles
+  can :read, :all        # has permission to read any model
+  can :manage, :all      # has permission to do anything to any model
 
-  can :update, Article do |article|
+You can pass a hash of conditions as the third argument to further restrict what the user is able to access. Here the user will only have permission to read active projects which he owns.
-    article && article.user == user
+
+  can :read, Project, :active => true, :user_id => user.id
+
+See {Defining Abilities with Hashes}[http://wiki.github.com/ryanb/cancan/defining-abilities-with-hashes] for more information.
+
+Blocks can also be used if you need more control.
+
+  can :update, Project do |project|
+    project && project.groups.include?(user.group)
   end
 
-If the block returns true then the user has that :update ability for that article, otherwise he will be denied access. It's possible for the passed in model to be nil if one isn't specified, so be sure to take that into consideration.
+If the block returns true then the user has that :+update+ ability for that project, otherwise he will be denied access. See {Defining Abilities with Blocks}[http://wiki.github.com/ryanb/cancan/defining-abilities-with-blocks] for more information.
 
-You can pass :all to reference every type of object. In this case the object type will be passed into the block as well (just in case object is nil).
 
-  can :read, :all do |object_class, object|
+== Aliasing Actions
-    object_class != Order
-  end
 
-Here the user has permission to read all objects except orders.
+You will usually be working with four actions when defining and checking permissions: :+read+, :+create+, :+update+, :+destroy+. These aren't the same as the 7 RESTful actions in Rails. CanCan automatically adds some default aliases for mapping those actions.
-
-You can also pass :manage as the action which will match any action. In this case the action is passed to the block.
-
-  can :manage, Comment do |action, comment|
-    action != :destroy
-  end
-
-Finally, you can use the "alias_action" method to alias one or more actions into one.
-
-  alias_action :update, :destroy, :to => :modify
-  can :modify, Comment
-
-The following aliases are added by default for conveniently mapping common controller actions.
 
   alias_action :index, :show, :to => :read
   alias_action :new, :to => :create
   alias_action :edit, :to => :update
 
+Notice the +edit+ action is aliased to +update+. If the user is able to update a record he also has permission to edit it. You can define your own aliases in the +Ability+ class
 
-== Checking Abilities
+  alias_action :update, :destroy, :to => :modify
+  can :modify, Comment
+  can? :update, Comment # => true
 
-Use the "can?" method in the controller or view to check the user's permission for a given action and object.
+See {Custom Actions}[http://wiki.github.com/ryanb/cancan/custom-actions] for information on adding other actions.
-
-  can? :destroy, @project
-
-You can also pass the class instead of an instance (if you don't have one handy). For example:
-
-  <% if can? :create, Project %>
-    <%= link_to "New Project", new_project_path %>
-  <% end %>
 
 
-== Custom Actions
+== Fetching Records
 
-There is no limit to what actions you can use to determine abilities. For example, if only pro users are allowed to upload a picture for their product, you might add restrictions like this.
+In the controller +index+ action you may want to fetch only the records which the user has permission to read. You can do this with the +accessible_by+ scope.
 
-  # ability.rb
+  @articles = Article.accessible_by(current_ability)
-  can :upload_picture, Project if user.pro?
 
-  # projects/_form.html.erb
+This will only work when abilities are defined using hash conditions, not blocks. See {Fetching Records}[http://wiki.github.com/ryanb/cancan/fetching-records] for more information.
-  <%= f.file_field :picture if can? :upload_picture, @project %>
-  
-  # projects_controller.rb
-  def update
-    unauthorized! if params[:project][:upload_picture] && !can?(:upload_picture, @project)
-    # ...
-  end
 
 
-== Customizing Assumptions
+== Additional Docs
 
-CanCan makes two assumptions about your application.
+* {Upgrading to 1.3}[http://wiki.github.com/ryanb/cancan/upgrading-to-13]
+* {Nested Resources}[http://wiki.github.com/ryanb/cancan/nested-resources]
+* {Testing Abilities}[http://wiki.github.com/ryanb/cancan/testing-abilities]
+* {Accessing Request Data}[http://wiki.github.com/ryanb/cancan/accessing-request-data]
+* {Admin Namespace}[http://wiki.github.com/ryanb/cancan/admin-namespace]
+* {See more}[http://wiki.github.com/ryanb/cancan/]
 
-  * The permissions are defined in Ability#prepare.
+== Special Thanks
-  * The user is fetched with current_user method in the controller.
 
-You can override these by defining the "current_ability" method in your ApplicationController.
+CanCan was inspired by declarative_authorization[http://github.com/stffn/declarative_authorization/] and aegis[http://github.com/makandra/aegis]. Also many thanks to the CanCan contributors[http://github.com/ryanb/cancan/contributors]. See the CHANGELOG[http://github.com/ryanb/cancan/blob/master/CHANGELOG.rdoc] for the full list.
-
-   def current_ability
-     ability = UserAbility.new          # instead of Ability
-     ability.prepare(current_account)   # instead of current_user
-     ability                            # be sure to return the ability
-   end
-
-That's it!
-
-
-== Permissions in Database
-
-Perhaps a non-coder needs the ability to modify the user abilities, or you want to change them without having to re-deploy the application. In that case it may be best to store the permission logic in a separate model, let's call it Permission. It is easy to use the database records when defining abilities.
-
-For example, let's assume that each user has_many :permissions, and each permission has "action", "object_type" and "object_id" columns. The last of which is optional.
-
-  class Ability
-    include CanCan::Ability
-  
-    def prepare(user)
-      can :manage, :all do |action, object_class, object|
-        user.permissions.find_all_by_action(action).any? do |permission|
-          permission.object_type.constantize == object_class &&
-            (object.nil? || permission.object_id.nil? || permission.object_id == object.id)
-        end
-      end
-    end
-  end
-
-The actual details will depend largely on your application requirements, but hopefully you can see how it's possible to define permissions in the database and use them with CanCan.

Rakefile

@@ -9,3 +9,5 @@ Spec::Rake::SpecTask.new do |t|
   t.spec_files = spec_files
   t.spec_opts = ["-c"]
 end
+
+task :default => :spec

cancan.gemspec

@@ -1,22 +1,15 @@
 Gem::Specification.new do |s|
   s.name        = "cancan"
-  s.summary = "Simple authorization solution for Rails."
+  s.version     = "1.3.4"
-  s.description = "Simple authorization solution for Rails which is completely decoupled from the user's roles. All permissions are stored in a single location for convenience."
+  s.author      = "Ryan Bates"
-  s.homepage = "http://github.com/ryanb/cancan"
-  
-  s.version = "0.1.0"
-  s.date = "2009-11-16"
-  
-  s.authors = ["Ryan Bates"]
   s.email       = "ryan@railscasts.com"
+  s.homepage    = "http://github.com/ryanb/cancan"
+  s.summary     = "Simple authorization solution for Rails."
+  s.description = "Simple authorization solution for Rails which is decoupled from user roles. All permissions are stored in a single location."
 
-  s.require_paths = ["lib"]
+  s.files        = Dir["{lib,spec}/**/*", "[A-Z]*", "init.rb"]
-  s.files = Dir["lib/**/*"] + Dir["spec/**/*"] + ["LICENSE", "README.rdoc", "Rakefile", "CHANGELOG.rdoc", "init.rb"]
+  s.require_path = "lib"
-  s.extra_rdoc_files = ["README.rdoc", "CHANGELOG.rdoc", "LICENSE"]
 
-  s.has_rdoc = true
+  s.rubyforge_project = s.name
-  s.rdoc_options = ["--line-numbers", "--inline-source", "--title", "CanCan", "--main", "README.rdoc"]
+  s.required_rubygems_version = ">= 1.3.4"
-  
-  s.rubygems_version = "1.3.4"
-  s.required_rubygems_version = Gem::Requirement.new(">= 1.2")
 end

lib/cancan.rb

@@ -1,6 +1,7 @@
-module CanCan
+require 'cancan/ability'
-  class AccessDenied < StandardError; end
+require 'cancan/can_definition'
-end
+require 'cancan/controller_resource'
-
+require 'cancan/controller_additions'
-require File.dirname(__FILE__) + '/cancan/ability'
+require 'cancan/active_record_additions'
-require File.dirname(__FILE__) + '/cancan/controller_additions'
+require 'cancan/exceptions'
+require 'cancan/query'

lib/cancan/ability.rb

@@ -1,43 +1,224 @@
 module CanCan
+
+  # This module is designed to be included into an Ability class. This will
+  # provide the "can" methods for defining and checking abilities.
+  #
+  #   class Ability
+  #     include CanCan::Ability
+  #
+  #     def initialize(user)
+  #       if user.admin?
+  #         can :manage, :all
+  #       else
+  #         can :read, :all
+  #       end
+  #     end
+  #   end
+  #
   module Ability
-    attr_accessor :user
+    # Use to check if the user has permission to perform a given action on an object.
-    
+    #
-    def can?(original_action, target) # TODO this could use some refactoring
+    #   can? :destroy, @project
-      (@can_history || []).reverse.each do |can_action, can_target, can_block|
+    #
-        possible_actions_for(original_action).each do |action|
+    # You can also pass the class instead of an instance (if you don't have one handy).
-          if (can_action == :manage || can_action == action) && (can_target == :all || can_target == target || target.kind_of?(can_target))
+    #
-            if can_block.nil?
+    #   can? :create, Project
-              return true
+    #
-            else
+    # Any additional arguments will be passed into the "can" block definition. This
-              block_args = []
+    # can be used to pass more information about the user's request for example.
-              block_args << action if can_action == :manage
+    #
-              block_args << (target.class == Class ? target : target.class) if can_target == :all
+    #   can? :create, Project, request.remote_ip
-              block_args << (target.class == Class ? nil : target)
+    #
-              return can_block.call(*block_args)
+    #   can :create Project do |project, remote_ip|
+    #     # ...
+    #   end
+    #
+    # Not only can you use the can? method in the controller and view (see ControllerAdditions),
+    # but you can also call it directly on an ability instance.
+    #
+    #   ability.can? :destroy, @project
+    #
+    # This makes testing a user's abilities very easy.
+    #
+    #   def test "user can only destroy projects which he owns"
+    #     user = User.new
+    #     ability = Ability.new(user)
+    #     assert ability.can?(:destroy, Project.new(:user => user))
+    #     assert ability.cannot?(:destroy, Project.new)
+    #   end
+    #
+    # Also see the RSpec Matchers to aid in testing.
+    def can?(action, subject, *extra_args)
+      raise Error, "Nom nom nom. I eated it." if action == :has && subject == :cheezburger
+      match = relevant_can_definitions(action, subject).detect do |can_definition|
+        can_definition.matches_conditions?(action, subject, extra_args)
       end
-          end
+      match ? match.base_behavior : false
-        end
-      end
-      false
     end
 
-    def possible_actions_for(initial_action)
+    # Convenience method which works the same as "can?" but returns the opposite value.
-      actions = [initial_action]
+    #
-      (@aliased_actions || default_alias_actions).each do |target, aliases|
+    #   cannot? :destroy, @project
-        actions += possible_actions_for(target) if aliases.include? initial_action
+    #
-      end
+    def cannot?(*args)
-      actions
+      !can?(*args)
     end
 
-    def can(action, target, &block)
+    # Defines which abilities are allowed using two arguments. The first one is the action
-      @can_history ||= []
+    # you're setting the permission for, the second one is the class of object you're setting it on.
-      @can_history << [action, target, block]
+    #
+    #   can :update, Article
+    #
+    # You can pass an array for either of these parameters to match any one.
+    #
+    #   can [:update, :destroy], [Article, Comment]
+    #
+    # In this case the user has the ability to update or destroy both articles and comments.
+    #
+    # You can pass a hash of conditions as the third argument.
+    #
+    #   can :read, Project, :active => true, :user_id => user.id
+    #
+    # Here the user can only see active projects which he owns. See ActiveRecordAdditions#accessible_by
+    # for how to use this in database queries.
+    #
+    # If the conditions hash does not give you enough control over defining abilities, you can use a block to
+    # write any Ruby code you want.
+    #
+    #   can :update, Project do |project|
+    #     project && project.groups.include?(user.group)
+    #   end
+    #
+    # If the block returns true then the user has that :update ability for that project, otherwise he
+    # will be denied access. It's possible for the passed in model to be nil if one isn't specified,
+    # so be sure to take that into consideration.
+    #
+    # The downside to using a block is that it cannot be used to generate conditions for database queries.
+    #
+    # You can pass :all to reference every type of object. In this case the object type will be passed
+    # into the block as well (just in case object is nil).
+    #
+    #   can :read, :all do |object_class, object|
+    #     object_class != Order
+    #   end
+    #
+    # Here the user has permission to read all objects except orders.
+    #
+    # You can also pass :manage as the action which will match any action. In this case the action is
+    # passed to the block.
+    #
+    #   can :manage, Comment do |action, comment|
+    #     action != :destroy
+    #   end
+    #
+    # You can pass custom objects into this "can" method, this is usually done through a symbol
+    # and is useful if a class isn't available to define permissions on.
+    #
+    #   can :read, :stats
+    #   can? :read, :stats # => true
+    #
+    def can(action, subject, conditions = nil, &block)
+      can_definitions << CanDefinition.new(true, action, subject, conditions, block)
     end
 
+    # Defines an ability which cannot be done. Accepts the same arguments as "can".
+    #
+    #   can :read, :all
+    #   cannot :read, Comment
+    #
+    # A block can be passed just like "can", however if the logic is complex it is recommended
+    # to use the "can" method.
+    #
+    #   cannot :read, Product do |product|
+    #     product.invisible?
+    #   end
+    #
+    def cannot(action, subject, conditions = nil, &block)
+      can_definitions << CanDefinition.new(false, action, subject, conditions, block)
+    end
+
+    # Alias one or more actions into another one.
+    #
+    #   alias_action :update, :destroy, :to => :modify
+    #   can :modify, Comment
+    #
+    # Then :modify permission will apply to both :update and :destroy requests.
+    #
+    #   can? :update, Comment # => true
+    #   can? :destroy, Comment # => true
+    #
+    # This only works in one direction. Passing the aliased action into the "can?" call
+    # will not work because aliases are meant to generate more generic actions.
+    #
+    #   alias_action :update, :destroy, :to => :modify
+    #   can :update, Comment
+    #   can? :modify, Comment # => false
+    #
+    # Unless that exact alias is used.
+    #
+    #   can :modify, Comment
+    #   can? :modify, Comment # => true
+    #
+    # The following aliases are added by default for conveniently mapping common controller actions.
+    #
+    #   alias_action :index, :show, :to => :read
+    #   alias_action :new, :to => :create
+    #   alias_action :edit, :to => :update
+    #
+    # This way one can use params[:action] in the controller to determine the permission.
     def alias_action(*args)
-      @aliased_actions ||= default_alias_actions
       target = args.pop[:to]
-      @aliased_actions[target] = args
+      aliased_actions[target] ||= []
+      aliased_actions[target] += args
+    end
+
+    # Returns a hash of aliased actions. The key is the target and the value is an array of actions aliasing the key.
+    def aliased_actions
+      @aliased_actions ||= default_alias_actions
+    end
+
+    # Removes previously aliased actions including the defaults.
+    def clear_aliased_actions
+      @aliased_actions = {}
+    end
+
+    # Returns a CanCan::Query instance to help generate database queries based on the ability.
+    # If any relevant can definitions use a block then an exception will be raised because an
+    # SQL query cannot be generated from blocks of code.
+    def query(action, subject)
+      Query.new(subject, relevant_can_definitions_for_query(action, subject))
+    end
+
+    private
+
+    # Accepts a hash of aliased actions and returns an array of actions which match.
+    # This should be called before "matches?" and other checking methods since they
+    # rely on the actions to be expanded.
+    def expand_actions(actions)
+      actions.map do |action|
+        aliased_actions[action] ? [action, *expand_actions(aliased_actions[action])] : action
+      end.flatten
+    end
+
+    def can_definitions
+      @can_definitions ||= []
+    end
+
+    # Returns an array of CanDefinition instances which match the action and subject
+    # This does not take into consideration any hash conditions or block statements
+    def relevant_can_definitions(action, subject)
+      can_definitions.reverse.select do |can_definition|
+        can_definition.expanded_actions = expand_actions(can_definition.actions)
+        can_definition.relevant? action, subject
+      end
+    end
+
+    def relevant_can_definitions_for_query(action, subject)
+      relevant_can_definitions(action, subject).each do |can_definition|
+        if can_definition.only_block?
+          raise Error, "The accessible_by call cannot be used with a block 'can' definition. The SQL cannot be determined for #{action.inspect} #{subject.inspect}"
+        end
+      end
     end
 
     def default_alias_actions
@@ -47,9 +228,5 @@ module CanCan
         :update => [:edit],
       }
     end
-    
-    def prepare(user)
-      # to be overriden by included class
-    end
   end
 end

lib/cancan/active_record_additions.rb

@@ -0,0 +1,42 @@
+module CanCan
+  # This module is automatically included into all Active Record models.
+  module ActiveRecordAdditions
+    module ClassMethods
+      # Returns a scope which fetches only the records that the passed ability
+      # can perform a given action on. The action defaults to :read. This
+      # is usually called from a controller and passed the +current_ability+.
+      #
+      #   @articles = Article.accessible_by(current_ability)
+      #
+      # Here only the articles which the user is able to read will be returned.
+      # If the user does not have permission to read any articles then an empty
+      # result is returned. Since this is a scope it can be combined with any
+      # other scopes or pagination.
+      #
+      # An alternative action can optionally be passed as a second argument.
+      #
+      #   @articles = Article.accessible_by(current_ability, :update)
+      #
+      # Here only the articles which the user can update are returned. This
+      # internally uses Ability#conditions method, see that for more information.
+      def accessible_by(ability, action = :read)
+        query = ability.query(action, self)
+        if respond_to? :where
+          where(query.conditions).joins(query.joins)
+        else
+          scoped(:conditions => query.conditions, :joins => query.joins)
+        end
+      end
+    end
+
+    def self.included(base)
+      base.extend ClassMethods
+    end
+  end
+end
+
+if defined? ActiveRecord
+  ActiveRecord::Base.class_eval do
+    include CanCan::ActiveRecordAdditions
+  end
+end

lib/cancan/can_definition.rb

@@ -0,0 +1,104 @@
+module CanCan
+  # This class is used internally and should only be called through Ability.
+  # it holds the information about a "can" call made on Ability and provides
+  # helpful methods to determine permission checking and conditions hash generation.
+  class CanDefinition # :nodoc:
+    attr_reader :base_behavior, :actions
+    attr_writer :expanded_actions
+
+    # The first argument when initializing is the base_behavior which is a true/false
+    # value. True for "can" and false for "cannot". The next two arguments are the action
+    # and subject respectively (such as :read, @project). The third argument is a hash
+    # of conditions and the last one is the block passed to the "can" call.
+    def initialize(base_behavior, action, subject, conditions, block)
+      @base_behavior = base_behavior
+      @actions = [action].flatten
+      @subjects = [subject].flatten
+      @conditions = conditions || {}
+      @block = block
+    end
+
+    # Matches both the subject and action, not necessarily the conditions
+    def relevant?(action, subject)
+      matches_action?(action) && matches_subject?(subject)
+    end
+
+    # Matches the block or conditions hash
+    def matches_conditions?(action, subject, extra_args)
+      if @block
+        call_block(action, subject, extra_args)
+      elsif @conditions.kind_of?(Hash) && subject.class != Class
+        matches_conditions_hash?(subject)
+      else
+        @base_behavior
+      end
+    end
+
+    def tableized_conditions(conditions = @conditions)
+      conditions.inject({}) do |result_hash, (name, value)|
+        if value.kind_of? Hash
+          name = name.to_s.tableize.to_sym
+          value = tableized_conditions(value)
+        end
+        result_hash[name] = value
+        result_hash
+      end
+    end
+
+    def only_block?
+      conditions_empty? && !@block.nil?
+    end
+
+    def conditions_empty?
+      @conditions == {} || @conditions.nil?
+    end
+
+    def associations_hash(conditions = @conditions)
+      hash = {}
+      conditions.map do |name, value|
+        hash[name] = associations_hash(value) if value.kind_of? Hash
+      end
+      hash
+    end
+
+    private
+
+    def matches_action?(action)
+      @expanded_actions.include?(:manage) || @expanded_actions.include?(action)
+    end
+
+    def matches_subject?(subject)
+      @subjects.include?(:all) || @subjects.include?(subject) || matches_subject_class?(subject)
+    end
+
+    def matches_subject_class?(subject)
+      @subjects.any? { |sub| sub.kind_of?(Class) && (subject.kind_of?(sub) || subject.kind_of?(Class) && subject.ancestors.include?(sub)) }
+    end
+
+    def matches_conditions_hash?(subject, conditions = @conditions)
+      conditions.all? do |name, value|
+        attribute = subject.send(name)
+        if value.kind_of?(Hash)
+          if attribute.kind_of? Array
+            attribute.any? { |element| matches_conditions_hash? element, value }
+          else
+            matches_conditions_hash? attribute, value
+          end
+        elsif value.kind_of?(Array) || value.kind_of?(Range)
+          value.include? attribute
+        else
+          attribute == value
+        end
+      end
+    end
+
+    def call_block(action, subject, extra_args)
+      block_args = []
+      block_args << action if @expanded_actions.include?(:manage)
+      block_args << (subject.class == Class ? subject : subject.class) if @subjects.include?(:all)
+      block_args << (subject.class == Class ? nil : subject)
+      block_args += extra_args
+      @block.call(*block_args)
+    end
+  end
+end

lib/cancan/controller_additions.rb

@@ -1,40 +1,239 @@
 module CanCan
+
+  # This module is automatically included into all controllers.
+  # It also makes the "can?" and "cannot?" methods available to all views.
   module ControllerAdditions
+    module ClassMethods
+      # Sets up a before filter which loads and authorizes the current resource. This performs both
+      # load_resource and authorize_resource and accepts the same arguments. See those methods for details.
+      #
+      #   class BooksController < ApplicationController
+      #     load_and_authorize_resource
+      #   end
+      #
+      def load_and_authorize_resource(*args)
+        ControllerResource.add_before_filter(self, :load_and_authorize_resource, *args)
+      end
+
+      # Sets up a before filter which loads the model resource into an instance variable.
+      # For example, given an ArticlesController it will load the current article into the @article
+      # instance variable. It does this by either calling Article.find(params[:id]) or
+      # Article.new(params[:article]) depending upon the action. It does nothing for the "index"
+      # action.
+      #
+      # Call this method directly on the controller class.
+      #
+      #   class BooksController < ApplicationController
+      #     load_resource
+      #   end
+      #
+      # A resource is not loaded if the instance variable is already set. This makes it easy to override
+      # the behavior through a before_filter on certain actions.
+      #
+      #   class BooksController < ApplicationController
+      #     before_filter :find_book_by_permalink, :only => :show
+      #     load_resource
+      #
+      #     private
+      #
+      #     def find_book_by_permalink
+      #       @book = Book.find_by_permalink!(params[:id)
+      #     end
+      #   end
+      #
+      # If a name is provided which does not match the controller it assumes it is a parent resource. Child
+      # resources can then be loaded through it.
+      #
+      #   class BooksController < ApplicationController
+      #     load_resource :author
+      #     load_resource :book, :through => :author
+      #   end
+      #
+      # Here the author resource will be loaded before each action using params[:author_id]. The book resource
+      # will then be loaded through the @author instance variable.
+      #
+      # That first argument is optional and will default to the singular name of the controller.
+      # A hash of options (see below) can also be passed to this method to further customize it.
+      #
+      # See load_and_authorize_resource to automatically authorize the resource too.
+      #
+      # Options:
+      # [:+only+]
+      #   Only applies before filter to given actions.
+      #
+      # [:+except+]
+      #   Does not apply before filter to given actions.
+      #
+      # [:+through+]
+      #   Load this resource through another one. This should match the name of the parent instance variable.
+      #
+      # [:+singleton+]
+      #   Pass +true+ if this is a singleton resource through a +has_one+ association.
+      #
+      # [:+parent+]
+      #   True or false depending on if the resource is considered a parent resource. This defaults to +true+ if a resource
+      #   name is given which does not match the controller.
+      #
+      # [:+class+]
+      #   The class to use for the model (string or constant).
+      #
+      # [:+instance_name+]
+      #   The name of the instance variable to load the resource into.
+      #
+      # [:+find_by+]
+      #   Find using a different attribute other than id. For example.
+      #
+      #     load_resource :find_by => :permalink # will use find_by_permlink!(params[:id])
+      #
+      # [:+collection+]
+      #   Specify which actions are resource collection actions in addition to :+index+. This
+      #   is usually not necessary because it will try to guess depending on if the id param is present.
+      #
+      #     load_resource :collection => [:sort, :list]
+      #
+      # [:+new+]
+      #   Specify which actions are new resource actions in addition to :+new+ and :+create+.
+      #   Pass an action name into here if you would like to build a new resource instead of
+      #   fetch one.
+      #
+      #     load_resource :new => :build
+      #
+      def load_resource(*args)
+        ControllerResource.add_before_filter(self, :load_resource, *args)
+      end
+
+      # Sets up a before filter which authorizes the resource using the instance variable.
+      # For example, if you have an ArticlesController it will check the @article instance variable
+      # and ensure the user can perform the current action on it. Under the hood it is doing
+      # something like the following.
+      #
+      #   authorize!(params[:action].to_sym, @article || Article)
+      #
+      # Call this method directly on the controller class.
+      #
+      #   class BooksController < ApplicationController
+      #     authorize_resource
+      #   end
+      #
+      # If you pass in the name of a resource which does not match the controller it will assume
+      # it is a parent resource.
+      #
+      #   class BooksController < ApplicationController
+      #     authorize_resource :author
+      #     authorize_resource :book
+      #   end
+      #
+      # Here it will authorize :+show+, @+author+ on every action before authorizing the book.
+      #
+      # That first argument is optional and will default to the singular name of the controller.
+      # A hash of options (see below) can also be passed to this method to further customize it.
+      #
+      # See load_and_authorize_resource to automatically load the resource too.
+      #
+      # Options:
+      # [:+only+]
+      #   Only applies before filter to given actions.
+      #
+      # [:+except+]
+      #   Does not apply before filter to given actions.
+      #
+      # [:+parent+]
+      #   True or false depending on if the resource is considered a parent resource. This defaults to +true+ if a resource
+      #   name is given which does not match the controller.
+      #
+      # [:+class+]
+      #   The class to use for the model (string or constant). This passed in when the instance variable is not set.
+      #   Pass +false+ if there is no associated class for this resource and it will use a symbol of the resource name.
+      #
+      # [:+instance_name+]
+      #   The name of the instance variable for this resource.
+      #
+      def authorize_resource(*args)
+        ControllerResource.add_before_filter(self, :authorize_resource, *args)
+      end
+    end
+
     def self.included(base)
-      base.helper_method :can?
+      base.extend ClassMethods
+      base.helper_method :can?, :cannot?
     end
 
-    def unauthorized!
+    # Raises a CanCan::AccessDenied exception if the current_ability cannot
-      raise AccessDenied, "You are unable to access this page."
+    # perform the given action. This is usually called in a controller action or
+    # before filter to perform the authorization.
+    #
+    #   def show
+    #     @article = Article.find(params[:id])
+    #     authorize! :read, @article
+    #   end
+    #
+    # A :message option can be passed to specify a different message.
+    #
+    #   authorize! :read, @article, :message => "Not authorized to read #{@article.name}"
+    #
+    # You can rescue from the exception in the controller to customize how unauthorized
+    # access is displayed to the user.
+    #
+    #   class ApplicationController < ActionController::Base
+    #     rescue_from CanCan::AccessDenied do |exception|
+    #       flash[:error] = exception.message
+    #       redirect_to root_url
+    #     end
+    #   end
+    #
+    # See the CanCan::AccessDenied exception for more details on working with the exception.
+    #
+    # See the load_and_authorize_resource method to automatically add the authorize! behavior
+    # to the default RESTful actions.
+    def authorize!(action, subject, *args)
+      message = nil
+      if args.last.kind_of?(Hash) && args.last.has_key?(:message)
+        message = args.pop[:message]
+      end
+      raise AccessDenied.new(message, action, subject) if cannot?(action, subject, *args)
     end
 
+    def unauthorized!(message = nil)
+      raise ImplementationRemoved, "The unauthorized! method has been removed from CanCan, use authorize! instead."
+    end
+
+    # Creates and returns the current user's ability and caches it. If you
+    # want to override how the Ability is defined then this is the place.
+    # Just define the method in the controller to change behavior.
+    #
+    #   def current_ability
+    #     # instead of Ability.new(current_user)
+    #     @current_ability ||= UserAbility.new(current_account)
+    #   end
+    #
+    # Notice it is important to cache the ability object so it is not
+    # recreated every time.
     def current_ability
-      ability = ::Ability.new
+      @current_ability ||= ::Ability.new(current_user)
-      ability.prepare(current_user)
-      ability
     end
 
+    # Use in the controller or view to check the user's permission for a given action
+    # and object.
+    #
+    #   can? :destroy, @project
+    #
+    # You can also pass the class instead of an instance (if you don't have one handy).
+    #
+    #   <% if can? :create, Project %>
+    #     <%= link_to "New Project", new_project_path %>
+    #   <% end %>
+    #
+    # This simply calls "can?" on the current_ability. See Ability#can?.
     def can?(*args)
-      (@current_ability ||= current_ability).can?(*args)
+      current_ability.can?(*args)
     end
 
-    def load_resource # TODO this could use some refactoring
+    # Convenience method which works the same as "can?" but returns the opposite value.
-      unless params[:action] == "index"
+    #
-        if params[:id]
+    #   cannot? :destroy, @project
-          instance_variable_set("@#{params[:controller].singularize}", params[:controller].singularize.camelcase.constantize.find(params[:id]))
+    #
-        else
+    def cannot?(*args)
-          instance_variable_set("@#{params[:controller].singularize}", params[:controller].singularize.camelcase.constantize.new(params[params[:controller].singularize.to_sym]))
+      current_ability.cannot?(*args)
-        end
-      end
-    end
-    
-    def authorize_resource # TODO this could use some refactoring
-      unauthorized! unless can?(params[:action].to_sym, instance_variable_get("@#{params[:controller].singularize}") || params[:controller].singularize.camelcase.constantize)
-    end
-    
-    def load_and_authorize_resource
-      load_resource
-      authorize_resource
     end
   end
 end

lib/cancan/controller_resource.rb

@@ -0,0 +1,129 @@
+module CanCan
+  # Handle the load and authorization controller logic so we don't clutter up all controllers with non-interface methods.
+  # This class is used internally, so you do not need to call methods directly on it.
+  class ControllerResource # :nodoc:
+    def self.add_before_filter(controller_class, method, *args)
+      options = args.extract_options!
+      resource_name = args.first
+      controller_class.before_filter(options.slice(:only, :except)) do |controller|
+        ControllerResource.new(controller, resource_name, options.except(:only, :except)).send(method)
+      end
+    end
+
+    def initialize(controller, *args)
+      @controller = controller
+      @params = controller.params
+      @options = args.extract_options!
+      @name = args.first
+      raise CanCan::ImplementationRemoved, "The :nested option is no longer supported, instead use :through with separate load/authorize call." if @options[:nested]
+      raise CanCan::ImplementationRemoved, "The :name option is no longer supported, instead pass the name as the first argument." if @options[:name]
+      raise CanCan::ImplementationRemoved, "The :resource option has been renamed back to :class, use false if no class." if @options[:resource]
+    end
+
+    def load_and_authorize_resource
+      load_resource
+      authorize_resource
+    end
+
+    def load_resource
+      if !resource_instance && (parent? || member_action?)
+        @controller.instance_variable_set("@#{instance_name}", load_resource_instance)
+      end
+    end
+
+    def authorize_resource
+      @controller.authorize!(authorization_action, resource_instance || resource_class)
+    end
+
+    def parent?
+      @options.has_key?(:parent) ? @options[:parent] : @name && @name != name_from_controller.to_sym
+    end
+
+    private
+
+    def load_resource_instance
+      if !parent? && new_actions.include?(@params[:action].to_sym)
+        build_resource
+      elsif id_param || @options[:singleton]
+        find_resource
+      end
+    end
+
+    def build_resource
+      method_name = @options[:singleton] ? "build_#{name}" : "new"
+      resource_base.send(*[method_name, @params[name]].compact)
+    end
+
+    def find_resource
+      if @options[:singleton]
+        resource_base.send(name)
+      else
+        @options[:find_by] ? resource_base.send("find_by_#{@options[:find_by]}!", id_param) : resource_base.find(id_param)
+      end
+    end
+
+    def authorization_action
+      parent? ? :read : @params[:action].to_sym
+    end
+
+    def id_param
+      @params[parent? ? :"#{name}_id" : :id]
+    end
+
+    def member_action?
+      !collection_actions.include? @params[:action].to_sym
+    end
+
+    # Returns the class used for this resource. This can be overriden by the :class option.
+    # If +false+ is passed in it will use the resource name as a symbol in which case it should
+    # only be used for authorization, not loading since there's no class to load through.
+    def resource_class
+      case @options[:class]
+      when false  then name.to_sym
+      when nil    then name.to_s.camelize.constantize
+      when String then @options[:class].constantize
+      else @options[:class]
+      end
+    end
+
+    def resource_instance
+      @controller.instance_variable_get("@#{instance_name}")
+    end
+
+    # The object that methods (such as "find", "new" or "build") are called on.
+    # If the :through option is passed it will go through an association on that instance.
+    # If the :singleton option is passed it won't use the association because it needs to be handled later.
+    def resource_base
+      if through_resource
+        @options[:singleton] ? through_resource : through_resource.send(name.to_s.pluralize)
+      else
+        resource_class
+      end
+    end
+
+    # The object to load this resource through.
+    def through_resource
+      @options[:through] && [@options[:through]].flatten.map { |i| @controller.instance_variable_get("@#{i}") }.compact.first
+    end
+
+    def name
+      @name || name_from_controller
+    end
+
+    def name_from_controller
+      @params[:controller].sub("Controller", "").underscore.split('/').last.singularize
+    end
+
+    def instance_name
+      @options[:instance_name] || name
+    end
+
+    def collection_actions
+      [:index] + [@options[:collection]].flatten
+    end
+
+    def new_actions
+      [:new, :create] + [@options[:new]].flatten
+    end
+  end
+end

lib/cancan/exceptions.rb

@@ -0,0 +1,43 @@
+module CanCan
+  # A general CanCan exception
+  class Error < StandardError; end
+
+  # Raised when removed code is called, an alternative solution is provided in message.
+  class ImplementationRemoved < Error; end
+
+  # This error is raised when a user isn't allowed to access a given controller action.
+  # This usually happens within a call to ControllerAdditions#authorize! but can be
+  # raised manually.
+  #
+  #   raise CanCan::AccessDenied.new("Not authorized!", :read, Article)
+  #
+  # The passed message, action, and subject are optional and can later be retrieved when
+  # rescuing from the exception.
+  #
+  #   exception.message # => "Not authorized!"
+  #   exception.action # => :read
+  #   exception.subject # => Article
+  #
+  # If the message is not specified (or is nil) it will default to "You are not authorized
+  # to access this page." This default can be overridden by setting default_message.
+  #
+  #   exception.default_message = "Default error message"
+  #   exception.message # => "Default error message"
+  #
+  # See ControllerAdditions#authorized! for more information on rescuing from this exception.
+  class AccessDenied < Error
+    attr_reader :action, :subject
+    attr_writer :default_message
+
+    def initialize(message = nil, action = nil, subject = nil)
+      @message = message
+      @action = action
+      @subject = subject
+      @default_message = "You are not authorized to access this page."
+    end
+
+    def to_s
+      @message || @default_message
+    end
+  end
+end

lib/cancan/matchers.rb

@@ -0,0 +1,14 @@
+RSpec = Spec unless defined? RSpec # for RSpec 1 compatability
+RSpec::Matchers.define :be_able_to do |*args|
+  match do |ability|
+    ability.can?(*args)
+  end
+
+  failure_message_for_should do |ability|
+    "expected to be able to #{args.map(&:inspect).join(" ")}"
+  end
+
+  failure_message_for_should_not do |ability|
+    "expected not to be able to #{args.map(&:inspect).join(" ")}"
+  end
+end

lib/cancan/query.rb

@@ -0,0 +1,97 @@
+module CanCan
+
+  # Generates the sql conditions and association joins for use in ActiveRecord queries.
+  # Normally you will not use this class directly, but instead through ActiveRecordAdditions#accessible_by.
+  class Query
+    def initialize(sanitizer, can_definitions)
+      @sanitizer = sanitizer
+      @can_definitions = can_definitions
+    end
+
+    # Returns conditions intended to be used inside a database query. Normally you will not call this
+    # method directly, but instead go through ActiveRecordAdditions#accessible_by.
+    #
+    # If there is only one "can" definition, a hash of conditions will be returned matching the one defined.
+    #
+    #   can :manage, User, :id => 1
+    #   query(:manage, User).conditions # => { :id => 1 }
+    #
+    # If there are multiple "can" definitions, a SQL string will be returned to handle complex cases.
+    #
+    #   can :manage, User, :id => 1
+    #   can :manage, User, :manager_id => 1
+    #   cannot :manage, User, :self_managed => true
+    #   query(:manage, User).conditions # => "not (self_managed = 't') AND ((manager_id = 1) OR (id = 1))"
+    #
+    def conditions
+      if @can_definitions.size == 1 && @can_definitions.first.base_behavior
+        # Return the conditions directly if there's just one definition
+        @can_definitions.first.tableized_conditions
+      else
+        @can_definitions.reverse.inject(false_sql) do |sql, can_definition|
+          merge_conditions(sql, can_definition.tableized_conditions, can_definition.base_behavior)
+        end
+      end
+    end
+
+    # Returns the associations used in conditions for the :joins option of a search.
+    # See ActiveRecordAdditions#accessible_by for use in Active Record.
+    def joins
+      joins_hash = {}
+      @can_definitions.each do |can_definition|
+        merge_joins(joins_hash, can_definition.associations_hash)
+      end
+      clean_joins(joins_hash) unless joins_hash.empty?
+    end
+
+    private
+
+    def merge_conditions(sql, conditions_hash, behavior)
+      if conditions_hash.blank?
+        behavior ? true_sql : false_sql
+      else
+        conditions = sanitize_sql(conditions_hash)
+        case sql
+        when true_sql
+          behavior ? true_sql : "not (#{conditions})"
+        when false_sql
+          behavior ? conditions : false_sql
+        else
+          behavior ? "(#{conditions}) OR (#{sql})" : "not (#{conditions}) AND (#{sql})"
+        end
+      end
+    end
+
+    def false_sql
+      sanitize_sql(['?=?', true, false])
+    end
+
+    def true_sql
+      sanitize_sql(['?=?', true, true])
+    end
+
+    def sanitize_sql(conditions)
+      @sanitizer.send(:sanitize_sql, conditions)
+    end
+
+    # Takes two hashes and does a deep merge.
+    def merge_joins(base, add)
+      add.each do |name, nested|
+        if base[name].is_a?(Hash) && !nested.empty?
+          merge_joins(base[name], nested)
+        else
+          base[name] = nested
+        end
+      end
+    end
+
+    # Removes empty hashes and moves everything into arrays.
+    def clean_joins(joins_hash)
+      joins = []
+      joins_hash.each do |name, nested|
+        joins << (nested.empty? ? name : {name => clean_joins(nested)})
+      end
+      joins
+    end
+  end
+end

spec/cancan/ability_spec.rb

@@ -1,10 +1,9 @@
-require File.dirname(__FILE__) + '/../spec_helper'
+require "spec_helper"
 
 describe CanCan::Ability do
   before(:each) do
-    @ability_class = Class.new
+    @ability = Object.new
-    @ability_class.send(:include, CanCan::Ability)
+    @ability.extend(CanCan::Ability)
-    @ability = @ability_class.new
   end
 
   it "should be able to :read anything" do
@@ -17,52 +16,81 @@ describe CanCan::Ability do
     @ability.can?(:foodfight, String).should be_false
   end
 
-  it "should return what block returns on a can call" do
+  it "should pass true to `can?` when non false/nil is returned in block" do
     @ability.can :read, :all
     @ability.can :read, Symbol do |sym|
-      sym
+      "foo" # TODO test that sym is nil when no instance is passed
     end
-    @ability.can?(:read, Symbol).should be_nil
+    @ability.can?(:read, :some_symbol).should == true
-    @ability.can?(:read, :some_symbol).should == :some_symbol
+  end
+
+  it "should pass to previous can definition, if block returns false or nil" do
+    @ability.can :read, Symbol
+    @ability.can :read, Integer do |i|
+      i < 5
+    end
+    @ability.can :read, Integer do |i|
+      i > 10
+    end
+    @ability.can?(:read, Symbol).should be_true
+    @ability.can?(:read, 11).should be_true
+    @ability.can?(:read, 1).should be_true
+    @ability.can?(:read, 6).should be_false
   end
 
   it "should pass class with object if :all objects are accepted" do
     @ability.can :preview, :all do |object_class, object|
-      [object_class, object]
+      object_class.should == Fixnum
+      object.should == 123
+      @block_called = true
     end
-    @ability.can?(:preview, 123).should == [Fixnum, 123]
+    @ability.can?(:preview, 123)
+    @block_called.should be_true
   end
 
   it "should pass class with no object if :all objects are accepted and class is passed directly" do
     @ability.can :preview, :all do |object_class, object|
-      [object_class, object]
+      object_class.should == Hash
+      object.should be_nil
+      @block_called = true
     end
-    @ability.can?(:preview, Hash).should == [Hash, nil]
+    @ability.can?(:preview, Hash)
+    @block_called.should be_true
   end
 
   it "should pass action and object for global manage actions" do
     @ability.can :manage, Array do |action, object|
-      [action, object]
+      action.should == :stuff
+      object.should == [1, 2]
+      @block_called = true
     end
-    @ability.can?(:stuff, [1, 2]).should == [:stuff, [1, 2]]
+    @ability.can?(:stuff, [1, 2]).should
-    @ability.can?(:stuff, Array).should == [:stuff, nil]
+    @block_called.should be_true
   end
 
   it "should alias update or destroy actions to modify action" do
     @ability.alias_action :update, :destroy, :to => :modify
-    @ability.can :modify, :all do |object_class, object|
+    @ability.can :modify, :all
-      :modify_called
+    @ability.can?(:update, 123).should be_true
+    @ability.can?(:destroy, 123).should be_true
   end
-    @ability.can?(:update, 123).should == :modify_called
+
-    @ability.can?(:destroy, 123).should == :modify_called
+  it "should allow deeply nested aliased actions" do
+    @ability.alias_action :increment, :to => :sort
+    @ability.alias_action :sort, :to => :modify
+    @ability.can :modify, :all
+    @ability.can?(:increment, 123).should be_true
   end
 
   it "should return block result for action, object_class, and object for any action" do
     @ability.can :manage, :all do |action, object_class, object|
-      [action, object_class, object]
+      action.should == :foo
+      object_class.should == Fixnum
+      object.should == 123
+      @block_called = true
     end
-    @ability.can?(:foo, 123).should == [:foo, Fixnum, 123]
+    @ability.can?(:foo, 123)
-    @ability.can?(:bar, Fixnum).should == [:bar, Fixnum, nil]
+    @block_called.should be_true
   end
 
   it "should automatically alias index and show into read calls" do
@@ -72,13 +100,163 @@ describe CanCan::Ability do
   end
 
   it "should automatically alias new and edit into create and update respectively" do
-    @ability.can(:create, :all) { :create_called }
+    @ability.can :create, :all
-    @ability.can(:update, :all) { :update_called }
+    @ability.can :update, :all
-    @ability.can?(:new, 123).should == :create_called
+    @ability.can?(:new, 123).should be_true
-    @ability.can?(:edit, 123).should == :update_called
+    @ability.can?(:edit, 123).should be_true
   end
 
-  it "should respond to prepare" do
+  it "should not respond to prepare (now using initialize)" do
-    @ability.should respond_to(:prepare)
+    @ability.should_not respond_to(:prepare)
+  end
+
+  it "should offer cannot? method which is simply invert of can?" do
+    @ability.cannot?(:tie, String).should be_true
+  end
+
+  it "should be able to specify multiple actions and match any" do
+    @ability.can [:read, :update], :all
+    @ability.can?(:read, 123).should be_true
+    @ability.can?(:update, 123).should be_true
+    @ability.can?(:count, 123).should be_false
+  end
+
+  it "should be able to specify multiple classes and match any" do
+    @ability.can :update, [String, Array]
+    @ability.can?(:update, "foo").should be_true
+    @ability.can?(:update, []).should be_true
+    @ability.can?(:update, 123).should be_false
+  end
+
+  it "should support custom objects in the can definition" do
+    @ability.can :read, :stats
+    @ability.can?(:read, :stats).should be_true
+    @ability.can?(:update, :stats).should be_false
+    @ability.can?(:read, :nonstats).should be_false
+  end
+
+  it "should check ancestors of class" do
+    @ability.can :read, Numeric
+    @ability.can?(:read, Integer).should be_true
+    @ability.can?(:read, 1.23).should be_true
+    @ability.can?(:read, "foo").should be_false
+  end
+
+  it "should support 'cannot' method to define what user cannot do" do
+    @ability.can :read, :all
+    @ability.cannot :read, Integer
+    @ability.can?(:read, "foo").should be_true
+    @ability.can?(:read, 123).should be_false
+  end
+
+  it "should support block on 'cannot' method" do
+    @ability.can :read, :all
+    @ability.cannot :read, Integer do |int|
+      int > 5
+    end
+    @ability.can?(:read, "foo").should be_true
+    @ability.can?(:read, 3).should be_true
+    @ability.can?(:read, 123).should be_false
+  end
+
+  it "should pass to previous can definition, if block returns false or nil" do
+    #same as previous
+    @ability.can :read, :all
+    @ability.cannot :read, Integer do |int|
+      int > 10 ? nil : ( int > 5 )
+    end
+    @ability.can?(:read, "foo").should be_true
+    @ability.can?(:read, 3).should be_true
+    @ability.can?(:read, 8).should be_false
+    @ability.can?(:read, 123).should be_true
+
+  end
+
+  it "should always return `false` for single cannot definition" do
+    @ability.cannot :read, Integer do |int|
+      int > 10 ? nil : ( int > 5 )
+    end
+    @ability.can?(:read, "foo").should be_false
+    @ability.can?(:read, 3).should be_false
+    @ability.can?(:read, 8).should be_false
+    @ability.can?(:read, 123).should be_false
+  end
+
+  it "should pass to previous cannot definition, if block returns false or nil" do
+    @ability.cannot :read, :all
+    @ability.can :read, Integer do |int|
+      int > 10 ? nil : ( int > 5 )
+    end
+    @ability.can?(:read, "foo").should be_false
+    @ability.can?(:read, 3).should be_false
+    @ability.can?(:read, 10).should be_true
+    @ability.can?(:read, 123).should be_false
+  end
+
+  it "should append aliased actions" do
+    @ability.alias_action :update, :to => :modify
+    @ability.alias_action :destroy, :to => :modify
+    @ability.aliased_actions[:modify].should == [:update, :destroy]
+  end
+
+  it "should clear aliased actions" do
+    @ability.alias_action :update, :to => :modify
+    @ability.clear_aliased_actions
+    @ability.aliased_actions[:modify].should be_nil
+  end
+
+  it "should pass additional arguments to block from can?" do
+    @ability.can :read, Integer do |int, x|
+      int > x
+    end
+    @ability.can?(:read, 2, 1).should be_true
+    @ability.can?(:read, 2, 3).should be_false
+  end
+
+  it "should use conditions as third parameter and determine abilities from it" do
+    @ability.can :read, Array, :first => 1, :last => 3
+    @ability.can?(:read, [1, 2, 3]).should be_true
+    @ability.can?(:read, [1, 2, 3, 4]).should be_false
+    @ability.can?(:read, Array).should be_true
+  end
+
+  it "should allow an array of options in conditions hash" do
+    @ability.can :read, Array, :first => [1, 3, 5]
+    @ability.can?(:read, [1, 2, 3]).should be_true
+    @ability.can?(:read, [2, 3]).should be_false
+    @ability.can?(:read, [3, 4]).should be_true
+  end
+
+  it "should allow a range of options in conditions hash" do
+    @ability.can :read, Array, :first => 1..3
+    @ability.can?(:read, [1, 2, 3]).should be_true
+    @ability.can?(:read, [3, 4]).should be_true
+    @ability.can?(:read, [4, 5]).should be_false
+  end
+
+  it "should allow nested hashes in conditions hash" do
+    @ability.can :read, Array, :first => { :length => 5 }
+    @ability.can?(:read, ["foo", "bar"]).should be_false
+    @ability.can?(:read, ["test1", "foo"]).should be_true
+  end
+
+  it "should allow nested hash of arrays and match any element" do
+    @ability.can :read, Array, :first => { :to_i => 3 }
+    @ability.can?(:read, [[1, 2, 3]]).should be_true
+    @ability.can?(:read, [[4, 5, 6]]).should be_false
+  end
+
+  it "should not stop at cannot definition when comparing class" do
+    @ability.can :read, Array
+    @ability.cannot :read, Array, :first => 1
+    @ability.can?(:read, [2, 3, 5]).should be_true
+    @ability.can?(:read, [1, 3, 5]).should be_false
+    @ability.can?(:read, Array).should be_true
+  end
+
+  it "should has eated cheezburger" do
+    lambda {
+      @ability.can? :has, :cheezburger
+    }.should raise_error(CanCan::Error, "Nom nom nom. I eated it.")
   end
 end

spec/cancan/active_record_additions_spec.rb

@@ -0,0 +1,51 @@
+require "spec_helper"
+
+describe CanCan::ActiveRecordAdditions do
+  before(:each) do
+    @model_class = Class.new(Person)
+    stub(@model_class).scoped { :scoped_stub }
+    @model_class.send(:include, CanCan::ActiveRecordAdditions)
+    @ability = Object.new
+    @ability.extend(CanCan::Ability)
+  end
+
+  it "should call where('true=false') when no ability is defined so no records are found" do
+    stub(@model_class).where('true=false').stub!.joins(nil) { :no_match }
+    @model_class.accessible_by(@ability, :read).should == :no_match
+  end
+
+  it "should call where with matching ability conditions" do
+    @ability.can :read, @model_class, :foo => {:bar => 1}
+    stub(@model_class).where(:foos => { :bar => 1 }).stub!.joins([:foo]) { :found_records }
+    @model_class.accessible_by(@ability, :read).should == :found_records
+  end
+
+  it "should default to :read ability and use scoped when where isn't available" do
+    @ability.can :read, @model_class, :foo => {:bar => 1}
+    stub(@model_class).scoped(:conditions => {:foos => {:bar => 1}}, :joins => [:foo]) { :found_records }
+    @model_class.accessible_by(@ability).should == :found_records
+  end
+
+  it "should merge association joins and sanitize conditions" do
+    @ability.can :read, @model_class, :foo => {:bar => 1}
+    @ability.can :read, @model_class, :too => {:car => 1, :far => {:bar => 1}}
+
+    condition_variants = [
+        '(toos.fars.bar=1 AND toos.car=1) OR (foos.bar=1)', # faked sql sanitizer is stupid ;-)
+        '(toos.car=1 AND toos.fars.bar=1) OR (foos.bar=1)'
+    ]
+    joins_variants = [
+        [:foo, {:too => [:far]}],
+        [{:too => [:far]}, :foo]
+    ]
+
+    condition_variants.each do |condition|
+      joins_variants.each do |joins|
+        stub(@model_class).scoped( :conditions => condition, :joins => joins ) { :found_records }
+      end
+    end
+    # @ability.conditions(:read, @model_class).should == '(too.car=1 AND too.far.bar=1) OR (foo.bar=1)'
+    # @ability.associations_hash(:read, @model_class).should == [{:too => [:far]}, :foo]
+    @model_class.accessible_by(@ability).should == :found_records
+  end
+end

spec/cancan/can_definition_spec.rb

@@ -0,0 +1,56 @@
+require "spec_helper"
+
+describe CanCan::CanDefinition do
+  before(:each) do
+    @conditions = {}
+    @can = CanCan::CanDefinition.new(true, :read, Integer, @conditions, nil)
+  end
+
+  it "should return no association joins if none exist" do
+    @can.associations_hash.should == {}
+  end
+
+  it "should return no association for joins if just attributes" do
+    @conditions[:foo] = :bar
+    @can.associations_hash.should == {}
+  end
+
+  it "should return single association for joins" do
+    @conditions[:foo] = {:bar => 1}
+    @can.associations_hash.should == {:foo => {}}
+  end
+
+  it "should return multiple associations for joins" do
+    @conditions[:foo] = {:bar => 1}
+    @conditions[:test] = {1 => 2}
+    @can.associations_hash.should == {:foo => {}, :test => {}}
+  end
+
+  it "should return nested associations for joins" do
+    @conditions[:foo] = {:bar => {1 => 2}}
+    @can.associations_hash.should == {:foo => {:bar => {}}}
+  end
+
+  it "should tableize correctly for absurdly complex permissions" do
+    @conditions[:unit] = {:property=>{:landlord=>{:weasle_id=>560}}}
+    @conditions[:test] = 1
+    @can.tableized_conditions.should == {:units => {:properties => {:landlords=>{:weasle_id=>560}}}, :test => 1}
+  end
+
+  it "should tableize correctly for complex permissions" do
+    @conditions[:unit] = {:property=>{:landlord_id=>560}}
+    @conditions[:test] = 1
+    @can.tableized_conditions.should == {:units => {:properties => {:landlord_id=>560}}, :test => 1}
+  end
+
+  it "should return table names in conditions for association joins" do
+    @conditions[:foo] = {:bar => 1}
+    @conditions[:test] = 1
+    @can.tableized_conditions.should == {:foos => {:bar => 1}, :test => 1}
+  end
+
+  it "should return no association joins if conditions is nil" do
+    can = CanCan::CanDefinition.new(true, :read, Integer, nil, nil)
+    can.associations_hash.should == {}
+  end
+end

spec/cancan/controller_additions_spec.rb

@@ -1,81 +1,78 @@
-require File.dirname(__FILE__) + '/../spec_helper'
+require "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?)
+    stub(@controller).params { {} }
+    stub(@controller).current_user { :current_user }
+    mock(@controller_class).helper_method(:can?, :cannot?)
     @controller_class.send(:include, CanCan::ControllerAdditions)
   end
 
-  it "should read from the cache with request uri as key and render that text" do
+  it "should raise ImplementationRemoved when attempting to call 'unauthorized!' on a controller" do
-    lambda {
+    lambda { @controller.unauthorized! }.should raise_error(CanCan::ImplementationRemoved)
-      @controller.unauthorized!
+  end
-    }.should raise_error(CanCan::AccessDenied)
+
+  it "should raise access denied exception if ability us unauthorized to perform a certain action" do
+    begin
+      @controller.authorize! :read, :foo, 1, 2, 3, :message => "Access denied!"
+    rescue CanCan::AccessDenied => e
+      e.message.should == "Access denied!"
+      e.action.should == :read
+      e.subject.should == :foo
+    else
+      fail "Expected CanCan::AccessDenied exception to be raised"
+    end
+  end
+
+  it "should not raise access denied exception if ability is authorized to perform an action" do
+    @controller.current_ability.can :read, :foo
+    lambda { @controller.authorize!(:read, :foo) }.should_not raise_error
+  end
+
+  it "should raise access denied exception with default message if not specified" do
+    begin
+      @controller.authorize! :read, :foo
+    rescue CanCan::AccessDenied => e
+      e.default_message = "Access denied!"
+      e.message.should == "Access denied!"
+    else
+      fail "Expected CanCan::AccessDenied exception to be raised"
+    end
   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)
   end
 
-  it "should provide a can? method which goes through the current ability" do
+  it "should provide a can? and cannot? methods which go 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
+    @controller.cannot?(:foo, :bar).should be_true
   end
 
-  it "should load the resource if params[:id] is specified" do
+  it "load_and_authorize_resource should setup a before filter which passes call to ControllerResource" do
-    stub(@controller).params { {:controller => "abilities", :action => "show", :id => 123} }
+    stub(CanCan::ControllerResource).new(@controller, nil, :foo => :bar).mock!.load_and_authorize_resource
-    stub(Ability).find(123) { :some_resource }
+    mock(@controller_class).before_filter({}) { |options, block| block.call(@controller) }
-    @controller.load_resource
+    @controller_class.load_and_authorize_resource :foo => :bar
-    @controller.instance_variable_get(:@ability).should == :some_resource
   end
 
-  it "should build a new resource with hash if params[:id] is not specified" do
+  it "load_and_authorize_resource should properly pass first argument as the resource name" do
-    stub(@controller).params { {:controller => "abilities", :action => "create", :ability => {:foo => "bar"}} }
+    stub(CanCan::ControllerResource).new(@controller, :project, :foo => :bar).mock!.load_and_authorize_resource
-    stub(Ability).new(:foo => "bar") { :some_resource }
+    mock(@controller_class).before_filter({}) { |options, block| block.call(@controller) }
-    @controller.load_resource
+    @controller_class.load_and_authorize_resource :project, :foo => :bar
-    @controller.instance_variable_get(:@ability).should == :some_resource
   end
 
-  it "should build a new resource even if attribute hash isn't specified" do
+  it "authorize_resource should setup a before filter which passes call to ControllerResource" do
-    stub(@controller).params { {:controller => "abilities", :action => "new"} }
+    stub(CanCan::ControllerResource).new(@controller, nil, :foo => :bar).mock!.authorize_resource
-    stub(Ability).new(nil) { :some_resource }
+    mock(@controller_class).before_filter(:except => :show) { |options, block| block.call(@controller) }
-    @controller.load_resource
+    @controller_class.authorize_resource :foo => :bar, :except => :show
-    @controller.instance_variable_get(:@ability).should == :some_resource
   end
 
-  it "should not build a resource when on index action" do
+  it "load_resource should setup a before filter which passes call to ControllerResource" do
-    stub(@controller).params { {:controller => "abilities", :action => "index"} }
+    stub(CanCan::ControllerResource).new(@controller, nil, :foo => :bar).mock!.load_resource
-    @controller.load_resource
+    mock(@controller_class).before_filter(:only => [:show, :index]) { |options, block| block.call(@controller) }
-    @controller.instance_variable_get(:@ability).should be_nil
+    @controller_class.load_resource :foo => :bar, :only => [:show, :index]
-  end
-  
-  it "should perform authorization using controller action and loaded model" do
-    @controller.instance_variable_set(:@ability, :some_resource)
-    stub(@controller).params { {:controller => "abilities", :action => "show"} }
-    stub(@controller).can?(:show, :some_resource) { false }
-    lambda {
-      @controller.authorize_resource
-    }.should raise_error(CanCan::AccessDenied)
-  end
-  
-  it "should perform authorization using controller action and non loaded model" do
-    stub(@controller).params { {:controller => "abilities", :action => "show"} }
-    stub(@controller).can?(:show, Ability) { false }
-    lambda {
-      @controller.authorize_resource
-    }.should raise_error(CanCan::AccessDenied)
-  end
-  
-  it "should load and authorize resource in one call" do
-    mock(@controller).load_resource
-    stub(@controller).authorize_resource
-    @controller.load_and_authorize_resource
   end
 end

spec/cancan/controller_resource_spec.rb

@@ -0,0 +1,251 @@
+require "spec_helper"
+
+describe CanCan::ControllerResource do
+  before(:each) do
+    @params = HashWithIndifferentAccess.new(:controller => "abilities")
+    @controller = Object.new # simple stub for now
+    stub(@controller).params { @params }
+  end
+
+  it "should load the resource into an instance variable if params[:id] is specified" do
+    @params.merge!(:action => "show", :id => 123)
+    stub(Ability).find(123) { :some_resource }
+    resource = CanCan::ControllerResource.new(@controller)
+    resource.load_resource
+    @controller.instance_variable_get(:@ability).should == :some_resource
+  end
+
+  it "should not load resource into an instance variable if already set" do
+    @params.merge!(:action => "show", :id => 123)
+    @controller.instance_variable_set(:@ability, :some_ability)
+    resource = CanCan::ControllerResource.new(@controller)
+    resource.load_resource
+    @controller.instance_variable_get(:@ability).should == :some_ability
+  end
+
+  it "should properly load resource for namespaced controller" do
+    @params.merge!(:controller => "admin/abilities", :action => "show", :id => 123)
+    stub(Ability).find(123) { :some_resource }
+    resource = CanCan::ControllerResource.new(@controller)
+    resource.load_resource
+    @controller.instance_variable_get(:@ability).should == :some_resource
+  end
+
+  it "should properly load resource for namespaced controller when using '::' for namespace" do
+    @params.merge!(:controller => "Admin::AbilitiesController", :action => "show", :id => 123)
+    stub(Ability).find(123) { :some_resource }
+    resource = CanCan::ControllerResource.new(@controller)
+    resource.load_resource
+    @controller.instance_variable_get(:@ability).should == :some_resource
+  end
+
+  it "should build a new resource with hash if params[:id] is not specified" do
+    @params.merge!(:action => "create", :ability => {:foo => "bar"})
+    stub(Ability).new("foo" => "bar") { :some_resource }
+    resource = CanCan::ControllerResource.new(@controller)
+    resource.load_resource
+    @controller.instance_variable_get(:@ability).should == :some_resource
+  end
+
+  it "should build a new resource with no arguments if attribute hash isn't specified" do
+    @params[:action] = "new"
+    mock(Ability).new { :some_resource }
+    resource = CanCan::ControllerResource.new(@controller)
+    resource.load_resource
+    @controller.instance_variable_get(:@ability).should == :some_resource
+  end
+
+  it "should not build a resource when on index action" do
+    @params[:action] = "index"
+    resource = CanCan::ControllerResource.new(@controller)
+    resource.load_resource
+    @controller.instance_variable_get(:@ability).should be_nil
+  end
+
+  it "should perform authorization using controller action and loaded model" do
+    @params[:action] = "show"
+    @controller.instance_variable_set(:@ability, :some_resource)
+    stub(@controller).authorize!(:show, :some_resource) { raise CanCan::AccessDenied }
+    resource = CanCan::ControllerResource.new(@controller)
+    lambda { resource.authorize_resource }.should raise_error(CanCan::AccessDenied)
+  end
+
+  it "should perform authorization using controller action and non loaded model" do
+    @params[:action] = "show"
+    stub(@controller).authorize!(:show, Ability) { raise CanCan::AccessDenied }
+    resource = CanCan::ControllerResource.new(@controller)
+    lambda { resource.authorize_resource }.should raise_error(CanCan::AccessDenied)
+  end
+
+  it "should call load_resource and authorize_resource for load_and_authorize_resource" do
+    @params[:action] = "show"
+    resource = CanCan::ControllerResource.new(@controller)
+    mock(resource).load_resource
+    mock(resource).authorize_resource
+    resource.load_and_authorize_resource
+  end
+
+  it "should not build a resource when on custom collection action" do
+    @params[:action] = "sort"
+    resource = CanCan::ControllerResource.new(@controller, :collection => [:sort, :list])
+    resource.load_resource
+    @controller.instance_variable_get(:@ability).should be_nil
+  end
+
+  it "should build a resource when on custom new action even when params[:id] exists" do
+    @params.merge!(:action => "build", :id => 123)
+    stub(Ability).new { :some_resource }
+    resource = CanCan::ControllerResource.new(@controller, :new => :build)
+    resource.load_resource
+    @controller.instance_variable_get(:@ability).should == :some_resource
+  end
+
+  it "should not try to load resource for other action if params[:id] is undefined" do
+    @params[:action] = "list"
+    resource = CanCan::ControllerResource.new(@controller)
+    resource.load_resource
+    @controller.instance_variable_get(:@ability).should be_nil
+  end
+
+  it "should be a parent resource when name is provided which doesn't match controller" do
+    resource = CanCan::ControllerResource.new(@controller, :person)
+    resource.should be_parent
+  end
+
+  it "should not be a parent resource when name is provided which matches controller" do
+    resource = CanCan::ControllerResource.new(@controller, :ability)
+    resource.should_not be_parent
+  end
+
+  it "should be parent if specified in options" do
+    resource = CanCan::ControllerResource.new(@controller, :ability, {:parent => true})
+    resource.should be_parent
+  end
+
+  it "should not be parent if specified in options" do
+    resource = CanCan::ControllerResource.new(@controller, :person, {:parent => false})
+    resource.should_not be_parent
+  end
+
+  it "should load parent resource through proper id parameter when supplying a resource with a different name" do
+    @params.merge!(:action => "index", :person_id => 123)
+    stub(Person).find(123) { :some_person }
+    resource = CanCan::ControllerResource.new(@controller, :person)
+    resource.load_resource
+    @controller.instance_variable_get(:@person).should == :some_person
+  end
+
+  it "should load parent resource for collection action" do
+    @params.merge!(:action => "index", :person_id => 456)
+    stub(Person).find(456) { :some_person }
+    resource = CanCan::ControllerResource.new(@controller, :person)
+    resource.load_resource
+    @controller.instance_variable_get(:@person).should == :some_person
+  end
+
+  it "should load resource through the association of another parent resource" do
+    @params.merge!(:action => "show", :id => 123)
+    person = Object.new
+    @controller.instance_variable_set(:@person, person)
+    stub(person).abilities.stub!.find(123) { :some_ability }
+    resource = CanCan::ControllerResource.new(@controller, :through => :person)
+    resource.load_resource
+    @controller.instance_variable_get(:@ability).should == :some_ability
+  end
+
+  it "should not load through parent resource if instance isn't loaded" do
+    @params.merge!(:action => "show", :id => 123)
+    stub(Ability).find(123) { :some_ability }
+    resource = CanCan::ControllerResource.new(@controller, :through => :person)
+    resource.load_resource
+    @controller.instance_variable_get(:@ability).should == :some_ability
+  end
+
+  it "should load through first matching if multiple are given" do
+    @params.merge!(:action => "show", :id => 123)
+    person = Object.new
+    @controller.instance_variable_set(:@person, person)
+    stub(person).abilities.stub!.find(123) { :some_ability }
+    resource = CanCan::ControllerResource.new(@controller, :through => [:thing, :person])
+    resource.load_resource
+    @controller.instance_variable_get(:@ability).should == :some_ability
+  end
+
+  it "should find record through has_one association with :singleton option" do
+    @params.merge!(:action => "show")
+    person = Object.new
+    @controller.instance_variable_set(:@person, person)
+    stub(person).ability { :some_ability }
+    resource = CanCan::ControllerResource.new(@controller, :through => :person, :singleton => true)
+    resource.load_resource
+    @controller.instance_variable_get(:@ability).should == :some_ability
+  end
+
+  it "should build record through has_one association with :singleton option" do
+    @params.merge!(:action => "create", :ability => :ability_attributes)
+    person = Object.new
+    @controller.instance_variable_set(:@person, person)
+    stub(person).build_ability(:ability_attributes) { :new_ability }
+    resource = CanCan::ControllerResource.new(@controller, :through => :person, :singleton => true)
+    resource.load_resource
+    @controller.instance_variable_get(:@ability).should == :new_ability
+  end
+
+  it "should only authorize :read action on parent resource" do
+    @params.merge!(:action => "new", :person_id => 123)
+    stub(Person).find(123) { :some_person }
+    stub(@controller).authorize!(:read, :some_person) { raise CanCan::AccessDenied }
+    resource = CanCan::ControllerResource.new(@controller, :person)
+    lambda { resource.load_and_authorize_resource }.should raise_error(CanCan::AccessDenied)
+  end
+
+  it "should load the model using a custom class" do
+    @params.merge!(:action => "show", :id => 123)
+    stub(Person).find(123) { :some_resource }
+    resource = CanCan::ControllerResource.new(@controller, :class => Person)
+    resource.load_resource
+    @controller.instance_variable_get(:@ability).should == :some_resource
+  end
+
+  it "should authorize based on resource name if class is false" do
+    @params.merge!(:action => "show", :id => 123)
+    stub(@controller).authorize!(:show, :ability) { raise CanCan::AccessDenied }
+    resource = CanCan::ControllerResource.new(@controller, :class => false)
+    lambda { resource.authorize_resource }.should raise_error(CanCan::AccessDenied)
+  end
+
+  it "should load and authorize using custom instance name" do
+    @params.merge!(:action => "show", :id => 123)
+    stub(Ability).find(123) { :some_ability }
+    stub(@controller).authorize!(:show, :some_ability) { raise CanCan::AccessDenied }
+    resource = CanCan::ControllerResource.new(@controller, :instance_name => :custom_ability)
+    lambda { resource.load_and_authorize_resource }.should raise_error(CanCan::AccessDenied)
+    @controller.instance_variable_get(:@custom_ability).should == :some_ability
+  end
+
+  it "should load resource using custom find_by attribute" do
+    @params.merge!(:action => "show", :id => 123)
+    stub(Ability).find_by_name!(123) { :some_resource }
+    resource = CanCan::ControllerResource.new(@controller, :find_by => :name)
+    resource.load_resource
+    @controller.instance_variable_get(:@ability).should == :some_resource
+  end
+
+  it "should raise ImplementationRemoved when adding :name option" do
+    lambda {
+      CanCan::ControllerResource.new(@controller, :name => :foo)
+    }.should raise_error(CanCan::ImplementationRemoved)
+  end
+
+  it "should raise ImplementationRemoved exception when specifying :resource option since it is no longer used" do
+    lambda {
+      CanCan::ControllerResource.new(@controller, :resource => Person)
+    }.should raise_error(CanCan::ImplementationRemoved)
+  end
+
+  it "should raise ImplementationRemoved exception when passing :nested option" do
+    lambda {
+      CanCan::ControllerResource.new(@controller, :nested => :person)
+    }.should raise_error(CanCan::ImplementationRemoved)
+  end
+end

spec/cancan/exceptions_spec.rb

@@ -0,0 +1,35 @@
+require "spec_helper"
+
+describe CanCan::AccessDenied do
+  describe "with action and subject" do
+    before(:each) do
+      @exception = CanCan::AccessDenied.new(nil, :some_action, :some_subject)
+    end
+
+    it "should have action and subject accessors" do
+      @exception.action.should == :some_action
+      @exception.subject.should == :some_subject
+    end
+
+    it "should have a changable default message" do
+      @exception.message.should == "You are not authorized to access this page."
+      @exception.default_message = "Unauthorized!"
+      @exception.message.should == "Unauthorized!"
+    end
+  end
+
+  describe "with only a message" do
+    before(:each) do
+      @exception = CanCan::AccessDenied.new("Access denied!")
+    end
+
+    it "should have nil action and subject" do
+      @exception.action.should be_nil
+      @exception.subject.should be_nil
+    end
+
+    it "should have passed message" do
+      @exception.message.should == "Access denied!"
+    end
+  end
+end

spec/cancan/matchers_spec.rb

@@ -0,0 +1,33 @@
+require "spec_helper"
+
+describe "be_able_to" do
+  it "delegates to can?" do
+    object = Object.new
+    mock(object).can?(:read, 123) { true }
+    object.should be_able_to(:read, 123)
+  end
+
+  it "reports a nice failure message for should" do
+    object = Object.new
+    mock(object).can?(:read, 123) { false }
+    expect do
+      object.should be_able_to(:read, 123)
+    end.should raise_error('expected to be able to :read 123')
+  end
+
+  it "reports a nice failure message for should not" do
+    object = Object.new
+    mock(object).can?(:read, 123) { true }
+    expect do
+      object.should_not be_able_to(:read, 123)
+    end.should raise_error('expected not to be able to :read 123')
+  end
+
+  it "delegates additional arguments to can? and reports in failure message" do
+    object = Object.new
+    mock(object).can?(:read, 123, 456) { false }
+    expect do
+      object.should be_able_to(:read, 123, 456)
+    end.should raise_error('expected to be able to :read 123 456')
+  end
+end

spec/cancan/query_spec.rb

@@ -0,0 +1,107 @@
+require "spec_helper"
+
+describe CanCan::Query do
+  before(:each) do
+    @ability = Object.new
+    @ability.extend(CanCan::Ability)
+  end
+
+  it "should have false conditions if no abilities match" do
+    @ability.query(:destroy, Person).conditions.should == "true=false"
+  end
+
+  it "should return hash for single `can` definition" do
+    @ability.can :read, Person, :blocked => false, :user_id => 1
+    @ability.query(:read, Person).conditions.should == { :blocked => false, :user_id => 1 }
+  end
+
+  it "should merge multiple can definitions into single SQL string joining with OR" do
+    @ability.can :read, Person, :blocked => false
+    @ability.can :read, Person, :admin => true
+    @ability.query(:read, Person).conditions.should == "(admin=true) OR (blocked=false)"
+  end
+
+  it "should merge multiple can definitions into single SQL string joining with OR and AND" do
+    @ability.can :read, Person, :blocked => false, :active => true
+    @ability.can :read, Person, :admin => true
+    @ability.query(:read, Person).conditions.should orderlessly_match("(blocked=false AND active=true) OR (admin=true)")
+  end
+
+  it "should merge multiple can definitions into single SQL string joining with OR and AND" do
+    @ability.can :read, Person, :blocked => false, :active => true
+    @ability.can :read, Person, :admin => true
+    @ability.query(:read, Person).conditions.should orderlessly_match("(blocked=false AND active=true) OR (admin=true)")
+  end
+
+  it "should return false conditions for cannot clause" do
+    @ability.cannot :read, Person
+    @ability.query(:read, Person).conditions.should == "true=false"
+  end
+
+  it "should return SQL for single `can` definition in front of default `cannot` condition" do
+    @ability.cannot :read, Person
+    @ability.can :read, Person, :blocked => false, :user_id => 1
+    @ability.query(:read, Person).conditions.should orderlessly_match("blocked=false AND user_id=1")
+  end
+
+  it "should return true condition for single `can` definition in front of default `can` condition" do
+    @ability.can :read, Person
+    @ability.can :read, Person, :blocked => false, :user_id => 1
+    @ability.query(:read, Person).conditions.should == 'true=true'
+  end
+
+  it "should return false condition for single `cannot` definition" do
+    @ability.cannot :read, Person, :blocked => true, :user_id => 1
+    @ability.query(:read, Person).conditions.should == 'true=false'
+  end
+
+  it "should return `false condition` for single `cannot` definition in front of default `cannot` condition" do
+    @ability.cannot :read, Person
+    @ability.cannot :read, Person, :blocked => true, :user_id => 1
+    @ability.query(:read, Person).conditions.should == 'true=false'
+  end
+
+  it "should return `not (sql)` for single `cannot` definition in front of default `can` condition" do
+    @ability.can :read, Person
+    @ability.cannot :read, Person, :blocked => true, :user_id => 1
+    @ability.query(:read, Person).conditions.should orderlessly_match("not (blocked=true AND user_id=1)")
+  end
+
+  it "should return appropriate sql conditions in complex case" do
+    @ability.can :read, Person
+    @ability.can :manage, Person, :id => 1
+    @ability.can :update, Person, :manager_id => 1
+    @ability.cannot :update, Person, :self_managed => true
+    @ability.query(:update, Person).conditions.should == 'not (self_managed=true) AND ((manager_id=1) OR (id=1))'
+    @ability.query(:manage, Person).conditions.should == {:id=>1}
+    @ability.query(:read, Person).conditions.should == 'true=true'
+  end
+
+  it "should have nil joins if no can definitions" do
+    @ability.query(:read, Person).joins.should be_nil
+  end
+
+  it "should have nil joins if no nested hashes specified in conditions" do
+    @ability.can :read, Person, :blocked => false
+    @ability.can :read, Person, :admin => true
+    @ability.query(:read, Person).joins.should be_nil
+  end
+
+  it "should merge separate joins into a single array" do
+    @ability.can :read, Person, :project => { :blocked => false }
+    @ability.can :read, Person, :company => { :admin => true }
+    @ability.query(:read, Person).joins.inspect.should orderlessly_match([:company, :project].inspect)
+  end
+
+  it "should merge same joins into a single array" do
+    @ability.can :read, Person, :project => { :blocked => false }
+    @ability.can :read, Person, :project => { :admin => true }
+    @ability.query(:read, Person).joins.should == [:project]
+  end
+
+  it "should merge complex, nested joins" do
+    @ability.can :read, Person, :project => { :bar => {:test => true} }, :company => { :bar => {:test => true} }
+    @ability.can :read, Person, :project => { :foo => {:bar => true}, :bar => {:zip => :zap} }
+    @ability.query(:read, Person).joins.inspect.should orderlessly_match([{:project => [:bar, :foo]}, {:company => [:bar]}].inspect)
+  end
+end

spec/matchers.rb

@@ -0,0 +1,13 @@
+Spec::Matchers.define :orderlessly_match do |original_string|
+  match do |given_string|
+    original_string.split('').sort == given_string.split('').sort
+  end
+
+  failure_message_for_should do |given_string|
+    "expected \"#{given_string}\" to have the same characters as \"#{original_string}\""
+  end
+
+  failure_message_for_should_not do |given_string|
+    "expected \"#{given_string}\" not to have the same characters as \"#{original_string}\""
+  end
+end

spec/spec.opts

@@ -0,0 +1 @@
+--color

spec/spec_helper.rb

@@ -4,8 +4,44 @@ require 'active_support'
 require 'active_record'
 require 'action_controller'
 require 'action_view'
-require File.dirname(__FILE__) + '/../lib/cancan.rb'
+require 'matchers'
+require 'cancan'
+require 'cancan/matchers'
 
 Spec::Runner.configure do |config|
   config.mock_with :rr
 end
+
+class Ability
+  include CanCan::Ability
+
+  def initialize(user)
+  end
+end
+
+# this class helps out in testing SQL conditions
+class Person
+  class << self
+    protected
+
+    def sanitize_sql(hash_cond)
+      case hash_cond
+      when Hash
+        sanitize_hash(hash_cond).join(' AND ')
+      when Array
+        hash_cond.shift.gsub('?'){"#{hash_cond.shift.inspect}"}
+      when String then hash_cond
+      end
+    end
+
+    def sanitize_hash(hash)
+      hash.map do |name, value|
+        if Hash === value
+          sanitize_hash(value).map{|cond| "#{name}.#{cond}"}
+        else
+          "#{name}=#{value}"
+        end
+      end.flatten
+    end
+  end
+end