releasing 1.6.5

Fixes bug in mongoid_adapter with empty conditions hash

.rvmrc

@@ -1,23 +1 @@
-#!/usr/bin/env bash
+rvm use 1.8.7@cancan --create
-
-# adapted from: http://rvm.beginrescueend.com/workflow/rvmrc/
-
-ruby_string="1.8.7"
-gemset_name="cancan"
-
-if rvm list strings | grep -q "${ruby_string}" ; then
-
-  # Load or create the specified environment
-  if [[ -d "${rvm_path:-$HOME/.rvm}/environments" \
-    && -s "${rvm_path:-$HOME/.rvm}/environments/${ruby_string}@${gemset_name}" ]] ; then
-    \. "${rvm_path:-$HOME/.rvm}/environments/${ruby_string}@${gemset_name}"
-  else
-    rvm --create  "${ruby_string}@${gemset_name}"
-  fi
-
-else
-
-  # Notify the user to install the desired interpreter before proceeding.
-  echo "${ruby_string} was not found, please run 'rvm install ${ruby_string}' and then cd back into the project directory."
-
-fi

CHANGELOG.rdoc

@@ -1,3 +1,75 @@
+1.6.5 (May 18, 2011)
+
+* pass action and subject through AccessDenied exception when :through isn't found - issue #366
+
+* many Mongoid adapter improvements (thanks rahearn, cardagin) - issues #363, #352, #343
+
+* allow :through option to work with private controller methods - issue #360
+
+* ensure Mongoid::Document is defined before loading Mongoid adapter - issue #359
+
+* many DataMapper adapter improvements (thanks emmanuel) - issue #355
+
+* handle checking nil attributes through associations (thanks thatothermitch) - issue #330
+
+* improve scope merging - issue #328
+
+
+
+1.6.4 (March 29, 2011)
+
+* Fixed mongoid 'or' error - see issue #322
+
+
+1.6.3 (March 25, 2011)
+
+* Make sure ActiveRecord::Relation is defined before checking conditions against it so Rails 2 is supported again - see issue #312
+
+* Return subject passed to authorize! - see issue #314
+
+
+1.6.2 (March 18, 2011)
+
+* Fixed instance loading when :singleton option is used - see issue #310
+
+
+1.6.1 (March 15, 2011)
+
+* Use Item.new instead of build_item for singleton resource so it doesn't effect database - see issue #304
+
+* Made accessible_by action default to :index and parent action default to :show instead of :read - see issue #302
+
+* Reverted Inherited Resources "collection" override since it doesn't seem to be working - see issue #305
+
+
+1.6.0 (March 11, 2011)
+
+* Added MetaWhere support - see issue #194 and #261
+
+* Allow Active Record scopes in Ability conditions - see issue #257
+
+* Added :if and :unless options to check_authorization - see issue #284
+
+* Several Inherited Resources fixes (thanks aq1018, tanordheim and stefanoverna)
+
+* Pass action name to accessible_by call when loading a collection (thanks amw)
+
+* Added :prepend option to load_and_authorize_resource to load before other filters - see issue #290
+
+* Fixed spacing issue in I18n message for multi-word model names - see issue #292
+
+* Load resource collection for any action which doesn't have an "id" parameter - see issue #296
+
+* Raise an exception when trying to make a Ability condition with both a hash of conditions and a block - see issue #269
+
+
+1.5.1 (January 20, 2011)
+
+* Fixing deeply nested conditions in Active Record adapter - see issue #246
+
+* Improving Mongoid support for multiple can and cannot definitions (thanks stellard) - see issue #239
+
+
 1.5.0 (January 11, 2011)
 
 * Added an Ability generator - see issue #170

Gemfile

@@ -2,16 +2,17 @@ source "http://rubygems.org"
 
 case ENV["MODEL_ADAPTER"]
 when nil, "active_record"
-  gem "sqlite3-ruby", :require => "sqlite3"
+  gem "sqlite3"
   gem "activerecord", :require => "active_record"
   gem "with_model"
+  gem "meta_where"
 when "data_mapper"
   gem "dm-core", "~> 1.0.2"
   gem "dm-sqlite-adapter", "~> 1.0.2"
   gem "dm-migrations", "~> 1.0.2"
 when "mongoid"
   gem "bson_ext", "~> 1.1"
-  gem "mongoid", "~> 2.0.0.beta.19"
+  gem "mongoid", "~> 2.0.0.beta.20"
 else
   raise "Unknown model adapter: #{ENV["MODEL_ADAPTER"]}"
 end

README.rdoc

@@ -7,7 +7,7 @@ CanCan is an authorization library for Ruby on Rails which restricts what resour
 
 == Installation
 
-In <b>Rails 3</b>, add this to your Gemfile.
+In <b>Rails 3</b>, add this to your Gemfile and run the +bundle+ command.
 
   gem "cancan"
 
@@ -22,13 +22,19 @@ Alternatively, you can install it as a plugin.
 
 == Getting Started
 
-CanCan expects a +current_user+ method to exist in controllers. First, set up some authentication (such as Authlogic[https://github.com/binarylogic/authlogic] or Devise[https://github.com/plataformatec/devise]). See {Changing Defaults}[https://github.com/ryanb/cancan/wiki/changing-defaults] if you need to customize this behavior.
+CanCan expects a +current_user+ method to exist in the controller. First, set up some authentication (such as Authlogic[https://github.com/binarylogic/authlogic] or Devise[https://github.com/plataformatec/devise]). See {Changing Defaults}[https://github.com/ryanb/cancan/wiki/changing-defaults] if you need different behavior.
 
-Next, make an +Ability+ class. CanCan 1.5 includes a generator for this.
+
+=== 1. Define Abilities
+
+User permissions are defined in an +Ability+ class. CanCan 1.5 includes a Rails 3 generator for creating this class.
 
   rails g cancan:ability
 
-This is where the user permission will be defined. See the comments in models/ability.rb and {Defining Abilities}[https://github.com/ryanb/cancan/wiki/defining-abilities] for details.
+See {Defining Abilities}[https://github.com/ryanb/cancan/wiki/defining-abilities] for details.
+
+
+=== 2. Check Abilities & Authorization
 
 The current user's permissions can then be checked using the <tt>can?</tt> and <tt>cannot?</tt> methods in the view and controller.
 
@@ -38,14 +44,14 @@ The current user's permissions can then be checked using the <tt>can?</tt> and <
 
 See {Checking Abilities}[https://github.com/ryanb/cancan/wiki/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.
+The <tt>authorize!</tt> 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])
     authorize! :read, @article
   end
 
-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.
+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 every action.
 
   class ArticlesController < ApplicationController
     load_and_authorize_resource
@@ -57,21 +63,34 @@ Setting this for every action can be tedious, therefore the +load_and_authorize_
 
 See {Authorizing Controller Actions}[https://github.com/ryanb/cancan/wiki/authorizing-controller-actions] for more information.
 
+
+=== 3. Handle Unauthorized Access
+
 If the user authorization fails, a <tt>CanCan::AccessDenied</tt> exception will be raised. You can catch this and modify its behavior in the +ApplicationController+.
 
   class ApplicationController < ActionController::Base
     rescue_from CanCan::AccessDenied do |exception|
-      flash[:alert] = exception.message
+      redirect_to root_url, :alert => exception.message
-      redirect_to root_url
     end
   end
 
 See {Exception Handling}[https://github.com/ryanb/cancan/wiki/exception-handling] for more information.
 
 
+=== 4. Lock It Down
+
+If you want to ensure authorization happens on every action in your application, add +check_authorization+ to your ApplicationController.
+
+  class ApplicationController < ActionController::Base
+    check_authorization
+  end
+
+This will raise an exception if authorization is not performed in an action. If you want to skip this add +skip_authorization_check+ to a controller subclass. See {Ensure Authorization}[https://github.com/ryanb/cancan/wiki/Ensure-Authorization] for more information.
+
+
 == Wiki Docs
 
-* {Upgrading to 1.5}[https://github.com/ryanb/cancan/wiki/Upgrading-to-1.5]
+* {Upgrading to 1.6}[https://github.com/ryanb/cancan/wiki/Upgrading-to-1.6]
 * {Defining Abilities}[https://github.com/ryanb/cancan/wiki/Defining-Abilities]
 * {Checking Abilities}[https://github.com/ryanb/cancan/wiki/Checking-Abilities]
 * {Authorizing Controller Actions}[https://github.com/ryanb/cancan/wiki/Authorizing-Controller-Actions]
@@ -82,9 +101,9 @@ See {Exception Handling}[https://github.com/ryanb/cancan/wiki/exception-handling
 
 == Questions or Problems?
 
-If you have any issues with CanCan which you cannot find the solution to in the documentation, please add an {issue on GitHub}[https://github.com/ryanb/cancan/issues] or fork the project and send a pull request.
+If you have any issues with CanCan which you cannot find the solution to in the documentation[https://github.com/ryanb/cancan/wiki], please add an {issue on GitHub}[https://github.com/ryanb/cancan/issues] or fork the project and send a pull request.
 
-To get the specs running you should call +bundle+ and then +rake+. Specs currently do not work in Ruby 1.9 due to the RR mocking framework. See the {spec/README}[https://github.com/ryanb/cancan/blob/master/spec/README.rdoc] for more information.
+To get the specs running you should call +bundle+ and then +rake+. See the {spec/README}[https://github.com/ryanb/cancan/blob/master/spec/README.rdoc] for more information.
 
 
 == Special Thanks

cancan.gemspec

@@ -1,6 +1,6 @@
 Gem::Specification.new do |s|
   s.name        = "cancan"
-  s.version     = "1.5.0"
+  s.version     = "1.6.5"
   s.author      = "Ryan Bates"
   s.email       = "ryan@railscasts.com"
   s.homepage    = "http://github.com/ryanb/cancan"

lib/cancan.rb

@@ -10,4 +10,4 @@ require 'cancan/model_adapters/abstract_adapter'
 require 'cancan/model_adapters/default_adapter'
 require 'cancan/model_adapters/active_record_adapter' if defined? ActiveRecord
 require 'cancan/model_adapters/data_mapper_adapter' if defined? DataMapper
-require 'cancan/model_adapters/mongoid_adapter' if defined? Mongoid
+require 'cancan/model_adapters/mongoid_adapter' if defined?(Mongoid) && defined?(Mongoid::Document)

lib/cancan/ability.rb

@@ -201,12 +201,13 @@ module CanCan
         message ||= unauthorized_message(action, subject)
         raise AccessDenied.new(message, action, subject)
       end
+      subject
     end
 
     def unauthorized_message(action, subject)
       keys = unauthorized_message_keys(action, subject)
       variables = {:action => action.to_s}
-      variables[:subject] = (subject.class == Class ? subject : subject.class).to_s.downcase
+      variables[:subject] = (subject.class == Class ? subject : subject.class).to_s.underscore.humanize.downcase
       message = I18n.translate(nil, variables.merge(:scope => :unauthorized, :default => keys + [""]))
       message.blank? ? nil : message
     end

lib/cancan/controller_additions.rb

@@ -109,6 +109,9 @@ module CanCan
       #
       #     load_resource :new => :build
       #
+      # [:+prepend+]
+      #   Passing +true+ will use prepend_before_filter instead of a normal before_filter.
+      #
       def load_resource(*args)
         cancan_resource_class.add_before_filter(self, :load_resource, *args)
       end
@@ -162,6 +165,9 @@ module CanCan
       # [:+through+]
       #   Authorize conditions on this parent resource when instance isn't available.
       #
+      # [:+prepend+]
+      #   Passing +true+ will use prepend_before_filter instead of a normal before_filter.
+      #
       def authorize_resource(*args)
         cancan_resource_class.add_before_filter(self, :authorize_resource, *args)
       end
@@ -220,16 +226,33 @@ module CanCan
       #     check_authorization
       #   end
       #
-      # Any arguments are passed to the +after_filter+ it triggers.
-      #
       # See skip_authorization_check to bypass this check on specific controller actions.
-      def check_authorization(*args)
+      #
-        self.after_filter(*args) do |controller|
+      # Options:
-          unless controller.instance_variable_defined?(:@_authorized)
+      # [:+only+]
+      #   Only applies to given actions.
+      #
+      # [:+except+]
+      #   Does not apply to given actions.
+      #
+      # [:+if+]
+      #   Supply the name of a controller method to be called. The authorization check only takes place if this returns true.
+      #
+      #     check_authorization :if => :admin_controller?
+      #
+      # [:+unless+]
+      #   Supply the name of a controller method to be called. The authorization check only takes place if this returns false.
+      #
+      #     check_authorization :unless => :devise_controller?
+      #
+      def check_authorization(options = {})
+        self.after_filter(options.slice(:only, :except)) do |controller|
+          return if controller.instance_variable_defined?(:@_authorized)
+          return if options[:if] && !controller.send(options[:if])
+          return if options[:unless] && controller.send(options[:unless])
           raise AuthorizationNotPerformed, "This action failed the check_authorization because it does not authorize_resource. Add skip_authorization_check to bypass this check."
         end
       end
-      end
 
       # Call this in the class of a controller to skip the check_authorization behavior on the actions.
       #
@@ -263,7 +286,7 @@ module CanCan
 
     def self.included(base)
       base.extend ClassMethods
-      base.helper_method :can?, :cannot?
+      base.helper_method :can?, :cannot?, :current_ability
     end
 
     # Raises a CanCan::AccessDenied exception if the current_ability cannot
@@ -294,8 +317,7 @@ module CanCan
     #
     #   class ApplicationController < ActionController::Base
     #     rescue_from CanCan::AccessDenied do |exception|
-    #       flash[:error] = exception.message
+    #       redirect_to root_url, :alert => exception.message
-    #       redirect_to root_url
     #     end
     #   end
     #

lib/cancan/controller_resource.rb

@@ -5,7 +5,8 @@ module CanCan
     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|
+      before_filter_method = options.delete(:prepend) ? :prepend_before_filter : :before_filter
+      controller_class.send(before_filter_method, options.slice(:only, :except)) do |controller|
         controller.class.cancan_resource_class.new(controller, resource_name, options.except(:only, :except)).send(method)
       end
     end
@@ -77,14 +78,14 @@ module CanCan
     end
 
     def load_collection
-      resource_base.accessible_by(current_ability)
+      resource_base.accessible_by(current_ability, authorization_action)
     end
 
     def build_resource
-      method_name = @options[:singleton] && resource_base.respond_to?("build_#{name}") ? "build_#{name}" : "new"
+      resource = resource_base.new(@params[name] || {})
-      resource = resource_base.send(method_name, @params[name] || {})
+      resource.send("#{parent_name}=", parent_resource) if @options[:singleton] && parent_resource
-      initial_attributes.each do |name, value|
+      initial_attributes.each do |attr_name, value|
-        resource.send("#{name}=", value)
+        resource.send("#{attr_name}=", value)
       end
       resource
     end
@@ -96,15 +97,15 @@ module CanCan
     end
 
     def find_resource
-      if @options[:singleton] && resource_base.respond_to?(name)
+      if @options[:singleton] && parent_resource.respond_to?(name)
-        resource_base.send(name)
+        parent_resource.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
+      parent? ? :show : @params[:action].to_sym
     end
 
     def id_param
@@ -112,7 +113,7 @@ module CanCan
     end
 
     def member_action?
-      !collection_actions.include? @params[:action].to_sym
+      new_actions.include?(@params[:action].to_sym) || @options[:singleton] || (@params[:id] && !collection_actions.include?(@params[:action].to_sym))
     end
 
     # Returns the class used for this resource. This can be overriden by the :class option.
@@ -154,26 +155,30 @@ module CanCan
     def resource_base
       if @options[:through]
         if parent_resource
-          @options[:singleton] ? parent_resource : parent_resource.send(@options[:through_association] || name.to_s.pluralize)
+          @options[:singleton] ? resource_class : parent_resource.send(@options[:through_association] || name.to_s.pluralize)
         elsif @options[:shallow]
           resource_class
         else
-          raise AccessDenied # maybe this should be a record not found error instead?
+          raise AccessDenied.new(nil, authorization_action, resource_class) # maybe this should be a record not found error instead?
         end
       else
         resource_class
       end
     end
 
+    def parent_name
+      @options[:through] && [@options[:through]].flatten.detect { |i| fetch_parent(i) }
+    end
+
     # The object to load this resource through.
     def parent_resource
-      @options[:through] && [@options[:through]].flatten.map { |i| fetch_parent(i) }.compact.first
+      parent_name && fetch_parent(parent_name)
     end
 
     def fetch_parent(name)
       if @controller.instance_variable_defined? "@#{name}"
         @controller.instance_variable_get("@#{name}")
-      elsif @controller.respond_to? name
+      elsif @controller.respond_to?(name, true)
         @controller.send(name)
       end
     end

lib/cancan/inherited_resource.rb

@@ -3,7 +3,8 @@ module CanCan
   class InheritedResource < ControllerResource # :nodoc:
     def load_resource_instance
       if parent?
-        @controller.send :parent
+        @controller.send :association_chain
+        @controller.instance_variable_get("@#{instance_name}")
       elsif new_actions.include? @params[:action].to_sym
         @controller.send :build_resource
       else

lib/cancan/model_adapters/abstract_adapter.rb

@@ -26,6 +26,17 @@ module CanCan
         raise NotImplemented, "This model adapter does not support matching on a conditions hash."
       end
 
+      # Used to determine if this model adapter will override the matching behavior for a specific condition.
+      # If this returns true then matches_condition? will be called. See Rule#matches_conditions_hash
+      def self.override_condition_matching?(subject, name, value)
+        false
+      end
+
+      # Override if override_condition_matching? returns true
+      def self.matches_condition?(subject, name, value)
+        raise NotImplemented, "This model adapter does not support matching on a specific condition."
+      end
+
       def initialize(model_class, rules)
         @model_class = model_class
         @rules = rules

lib/cancan/model_adapters/active_record_adapter.rb

@@ -5,6 +5,37 @@ module CanCan
         model_class <= ActiveRecord::Base
       end
 
+      def self.override_condition_matching?(subject, name, value)
+        name.kind_of?(MetaWhere::Column) if defined? MetaWhere
+      end
+
+      def self.matches_condition?(subject, name, value)
+        subject_value = subject.send(name.column)
+        if name.method.to_s.ends_with? "_any"
+          value.any? { |v| meta_where_match? subject_value, name.method.to_s.sub("_any", ""), v }
+        elsif name.method.to_s.ends_with? "_all"
+          value.all? { |v| meta_where_match? subject_value, name.method.to_s.sub("_all", ""), v }
+        else
+          meta_where_match? subject_value, name.method, value
+        end
+      end
+
+      def self.meta_where_match?(subject_value, method, value)
+        case method.to_sym
+        when :eq      then subject_value == value
+        when :not_eq  then subject_value != value
+        when :in      then value.include?(subject_value)
+        when :not_in  then !value.include?(subject_value)
+        when :lt      then subject_value < value
+        when :lteq    then subject_value <= value
+        when :gt      then subject_value > value
+        when :gteq    then subject_value >= value
+        when :matches then subject_value =~ Regexp.new("^" + Regexp.escape(value).gsub("%", ".*") + "$", true)
+        when :does_not_match then !meta_where_match?(subject_value, :matches, value)
+        else raise NotImplemented, "The #{method} MetaWhere condition is not supported."
+        end
+      end
+
       # Returns conditions intended to be used inside a database query. Normally you will not call this
       # method directly, but instead go through ModelAdditions#accessible_by.
       #
@@ -31,12 +62,13 @@ module CanCan
         end
       end
 
-      def tableized_conditions(conditions)
+      def tableized_conditions(conditions, model_class = @model_class)
         return conditions unless conditions.kind_of? Hash
         conditions.inject({}) do |result_hash, (name, value)|
           if value.kind_of? Hash
-            name = @model_class.reflect_on_association(name).table_name
+            association_class = model_class.reflect_on_association(name).class_name.constantize
-            value = tableized_conditions(value)
+            name = model_class.reflect_on_association(name).table_name.to_sym
+            value = tableized_conditions(value, association_class)
           end
           result_hash[name] = value
           result_hash
@@ -54,7 +86,9 @@ module CanCan
       end
 
       def database_records
-        if @model_class.respond_to?(:where) && @model_class.respond_to?(:joins)
+        if override_scope
+          @model_class.scoped.merge(override_scope)
+        elsif @model_class.respond_to?(:where) && @model_class.respond_to?(:joins)
           @model_class.where(conditions).joins(joins)
         else
           @model_class.scoped(:conditions => conditions, :joins => joins)
@@ -63,6 +97,18 @@ module CanCan
 
       private
 
+      def override_scope
+        conditions = @rules.map(&:conditions).compact
+        if defined?(ActiveRecord::Relation) && conditions.any? { |c| c.kind_of?(ActiveRecord::Relation) }
+          if conditions.size == 1
+            conditions.first
+          else
+            rule = @rules.detect { |rule| rule.conditions.kind_of?(ActiveRecord::Relation) }
+            raise Error, "Unable to merge an Active Record scope with other conditions. Instead use a hash or SQL for #{rule.actions.first} #{rule.subjects.first} ability."
+          end
+        end
+      end
+
       def merge_conditions(sql, conditions_hash, behavior)
         if conditions_hash.blank?
           behavior ? true_sql : false_sql

lib/cancan/model_adapters/data_mapper_adapter.rb

@@ -10,23 +10,22 @@ module CanCan
       end
 
       def self.matches_conditions_hash?(subject, conditions)
-        subject.class.all(:conditions => conditions).include?(subject) # TODO don't use a database query here for performance and other instances
+        collection = DataMapper::Collection.new(subject.query, [ subject ])
+        !!collection.first(conditions)
       end
 
       def database_records
-        scope = @model_class.all(:conditions => ["0=1"])
+        scope = @model_class.all(:conditions => ["0 = 1"])
-        conditions.each do |condition|
+        cans, cannots = @rules.partition { |r| r.base_behavior }
-          scope += @model_class.all(:conditions => condition)
+        return scope if cans.empty?
-        end
+        # apply unions first, then differences. this mean cannot overrides can
+        cans.each    { |r| scope += @model_class.all(:conditions => r.conditions) }
+        cannots.each { |r| scope -= @model_class.all(:conditions => r.conditions) }
         scope
       end
-
+    end # class DataMapper
-      def conditions
+  end # module ModelAdapters
-        @rules.map(&:conditions)
+end # module CanCan
-      end
-    end
-  end
-end
 
 DataMapper::Model.class_eval do
   include CanCan::ModelAdditions::ClassMethods

lib/cancan/model_adapters/mongoid_adapter.rb

@@ -6,7 +6,14 @@ module CanCan
       end
 
       def self.override_conditions_hash_matching?(subject, conditions)
-        conditions.any? { |k,v| !k.kind_of?(Symbol) }
+        conditions.any? do |k,v|
+          key_is_not_symbol = lambda { !k.kind_of?(Symbol) }
+          subject_value_is_array = lambda do
+            subject.respond_to?(k) && subject.send(k).is_a?(Array)
+          end
+
+          key_is_not_symbol.call || subject_value_is_array.call
+        end
       end
 
       def self.matches_conditions_hash?(subject, conditions)
@@ -16,20 +23,25 @@ module CanCan
       end
 
       def database_records
-        @model_class.where(conditions)
-      end
-
-      def conditions
         if @rules.size == 0
-          false_query
+          @model_class.where(:_id => {'$exists' => false, '$type' => 7}) # return no records in Mongoid
+        elsif @rules.size == 1 && @rules[0].conditions.is_a?(Mongoid::Criteria)
+          @rules[0].conditions
         else
-          @rules.first.conditions
+          # we only need to process can rules if
+          # there are no rules with empty conditions
+          rules = @rules.reject { |rule| rule.conditions.empty? }
+          process_can_rules = @rules.count == rules.count
+          rules.inject(@model_class.all) do |records, rule|
+            if process_can_rules && rule.base_behavior
+              records.or rule.conditions
+            elsif !rule.base_behavior
+              records.excludes rule.conditions
+            else
+              records
+            end
           end
         end
-
-      def false_query
-        # this query is sure to return no results
-        {:_id => {'$exists' => false, '$type' => 7}}  # type 7 is an ObjectID (default for _id)
       end
     end
   end

lib/cancan/model_additions.rb

@@ -4,7 +4,7 @@ module CanCan
   module ModelAdditions
     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
+      # can perform a given action on. The action defaults to :index. This
       # is usually called from a controller and passed the +current_ability+.
       #
       #   @articles = Article.accessible_by(current_ability)
@@ -19,7 +19,7 @@ module CanCan
       #   @articles = Article.accessible_by(current_ability, :update)
       #
       # Here only the articles which the user can update are returned.
-      def accessible_by(ability, action = :read)
+      def accessible_by(ability, action = :index)
         ability.model_adapter(self, action).database_records
       end
     end

lib/cancan/rule.rb

@@ -3,7 +3,7 @@ module CanCan
   # it holds the information about a "can" call made on Ability and provides
   # helpful methods to determine permission checking and conditions hash generation.
   class Rule # :nodoc:
-    attr_reader :base_behavior, :actions, :conditions
+    attr_reader :base_behavior, :subjects, :actions, :conditions
     attr_writer :expanded_actions
 
     # The first argument when initializing is the base_behavior which is a true/false
@@ -11,6 +11,7 @@ module CanCan
     # 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)
+      raise Error, "You are not able to supply a block with a hash of conditions in #{action} #{subject} ability. Use either one." if conditions.kind_of?(Hash) && !block.nil?
       @match_all = action.nil? && subject.nil?
       @base_behavior = base_behavior
       @actions = [action].flatten
@@ -21,7 +22,7 @@ module CanCan
 
     # Matches both the subject and action, not necessarily the conditions
     def relevant?(action, subject)
-      subject = subject.values.first if subject.kind_of? Hash
+      subject = subject.values.first if subject.class == Hash
       @match_all || (matches_action?(action) && matches_subject?(subject))
     end
 
@@ -31,7 +32,7 @@ module CanCan
         call_block_with_all(action, subject, extra_args)
       elsif @block && !subject_class?(subject)
         @block.call(subject, *extra_args)
-      elsif @conditions.kind_of?(Hash) && subject.kind_of?(Hash)
+      elsif @conditions.kind_of?(Hash) && subject.class == Hash
         nested_subject_matches_conditions?(subject)
       elsif @conditions.kind_of?(Hash) && !subject_class?(subject)
         matches_conditions_hash?(subject)
@@ -100,12 +101,15 @@ module CanCan
           model_adapter(subject).matches_conditions_hash? subject, conditions
         else
           conditions.all? do |name, value|
+            if model_adapter(subject).override_condition_matching? subject, name, value
+              model_adapter(subject).matches_condition? subject, name, value
+            else
               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
+                  !attribute.nil? && matches_conditions_hash?(attribute, value)
                 end
               elsif value.kind_of?(Array) || value.kind_of?(Range)
                 value.include? attribute
@@ -116,6 +120,7 @@ module CanCan
           end
         end
       end
+    end
 
     def nested_subject_matches_conditions?(subject_hash)
       parent, child = subject_hash.shift

spec/cancan/ability_spec.rb

@@ -250,6 +250,13 @@ describe CanCan::Ability do
     @ability.can?(:read, 4..6).should be_false
   end
   
+  it "should not match subjects return nil for methods that must match nested a nested conditions hash" do
+    mock(object_with_foo = Object.new).foo { :bar }
+    @ability.can :read, Array, :first => { :foo => :bar }
+    @ability.can?(:read, [object_with_foo]).should be_true
+    @ability.can?(:read, []).should be_false
+  end
+
   it "should not stop at cannot definition when comparing class" do
     @ability.can :read, Range
     @ability.cannot :read, Range, :begin => 1
@@ -291,6 +298,12 @@ describe CanCan::Ability do
     @ability.can?(:read, 123 => Range).should be_true
   end
   
+  it "should allow to check ability on Hash-like object" do
+    class Container < Hash; end
+    @ability.can :read, Container
+    @ability.can?(:read, Container.new).should be_true
+  end
+
   it "should have initial attributes based on hash conditions of 'new' action" do
     @ability.can :manage, Range, :foo => "foo", :hash => {:skip => "hashes"}
     @ability.can :create, Range, :bar => 123, :array => %w[skip arrays]
@@ -311,9 +324,11 @@ describe CanCan::Ability do
     end
   end
 
-  it "should not raise access denied exception if ability is authorized to perform an action" do
+  it "should not raise access denied exception if ability is authorized to perform an action and return subject" do
     @ability.can :read, :foo
-    lambda { @ability.authorize!(:read, :foo) }.should_not raise_error
+    lambda {
+      @ability.authorize!(:read, :foo).should == :foo
+    }.should_not raise_error
   end
 
   it "should know when block is used in conditions" do
@@ -351,6 +366,14 @@ describe CanCan::Ability do
     @ability.model_adapter(model_class, :read).should == :adapter_instance
   end
 
+  it "should raise an error when attempting to use a block with a hash condition since it's not likely what they want" do
+    lambda {
+      @ability.can :read, Array, :published => true do
+        false
+      end
+    }.should raise_error(CanCan::Error, "You are not able to supply a block with a hash of conditions in read Array ability. Use either one.")
+  end
+
   describe "unauthorized message" do
     after(:each) do
       I18n.backend = nil
@@ -389,6 +412,7 @@ describe CanCan::Ability do
     it "should have variables for action and subject" do
       I18n.backend.store_translations :en, :unauthorized => {:manage => {:all => "%{action} %{subject}"}} # old syntax for now in case testing with old I18n
       @ability.unauthorized_message(:update, Array).should == "update array"
+      @ability.unauthorized_message(:update, ArgumentError).should == "update argument error"
       @ability.unauthorized_message(:edit, 1..3).should == "edit range"
     end
   end

spec/cancan/controller_additions_spec.rb

@@ -6,7 +6,7 @@ describe CanCan::ControllerAdditions do
     @controller = @controller_class.new
     stub(@controller).params { {} }
     stub(@controller).current_user { :current_user }
-    mock(@controller_class).helper_method(:can?, :cannot?)
+    mock(@controller_class).helper_method(:can?, :cannot?, :current_ability)
     @controller_class.send(:include, CanCan::ControllerAdditions)
   end
 
@@ -42,6 +42,11 @@ describe CanCan::ControllerAdditions do
     @controller_class.load_and_authorize_resource :project, :foo => :bar
   end
 
+  it "load_and_authorize_resource with :prepend should prepend the before filter" do
+    mock(@controller_class).prepend_before_filter({})
+    @controller_class.load_and_authorize_resource :foo => :bar, :prepend => true
+  end
+
   it "authorize_resource should setup a before filter which passes call to ControllerResource" do
     stub(CanCan::ControllerResource).new(@controller, nil, :foo => :bar).mock!.authorize_resource
     mock(@controller_class).before_filter(:except => :show) { |options, block| block.call(@controller) }
@@ -61,17 +66,33 @@ describe CanCan::ControllerAdditions do
   end
 
   it "check_authorization should trigger AuthorizationNotPerformed in after filter" do
-    mock(@controller_class).after_filter(:some_options) { |options, block| block.call(@controller) }
+    mock(@controller_class).after_filter(:only => [:test]) { |options, block| block.call(@controller) }
     lambda {
-      @controller_class.check_authorization(:some_options)
+      @controller_class.check_authorization(:only => [:test])
     }.should raise_error(CanCan::AuthorizationNotPerformed)
   end
 
+  it "check_authorization should not trigger AuthorizationNotPerformed when :if is false" do
+    stub(@controller).check_auth? { false }
+    mock(@controller_class).after_filter({}) { |options, block| block.call(@controller) }
+    lambda {
+      @controller_class.check_authorization(:if => :check_auth?)
+    }.should_not raise_error(CanCan::AuthorizationNotPerformed)
+  end
+
+  it "check_authorization should not trigger AuthorizationNotPerformed when :unless is true" do
+    stub(@controller).engine_controller? { true }
+    mock(@controller_class).after_filter({}) { |options, block| block.call(@controller) }
+    lambda {
+      @controller_class.check_authorization(:unless => :engine_controller?)
+    }.should_not raise_error(CanCan::AuthorizationNotPerformed)
+  end
+
   it "check_authorization should not raise error when @_authorized is set" do
     @controller.instance_variable_set(:@_authorized, true)
-    mock(@controller_class).after_filter(:some_options) { |options, block| block.call(@controller) }
+    mock(@controller_class).after_filter(:only => [:test]) { |options, block| block.call(@controller) }
     lambda {
-      @controller_class.check_authorization(:some_options)
+      @controller_class.check_authorization(:only => [:test])
     }.should_not raise_error(CanCan::AuthorizationNotPerformed)
   end
 

spec/cancan/controller_resource_spec.rb

@@ -67,7 +67,7 @@ describe CanCan::ControllerResource do
   end
 
   it "should build a collection when on index action when class responds to accessible_by" do
-    stub(Project).accessible_by(@ability) { :found_projects }
+    stub(Project).accessible_by(@ability, :index) { :found_projects }
     @params[:action] = "index"
     resource = CanCan::ControllerResource.new(@controller, :project)
     resource.load_resource
@@ -104,13 +104,13 @@ describe CanCan::ControllerResource do
   it "should authorize parent resource in collection action" do
     @params[:action] = "index"
     @controller.instance_variable_set(:@category, :some_category)
-    stub(@controller).authorize!(:read, :some_category) { raise CanCan::AccessDenied }
+    stub(@controller).authorize!(:show, :some_category) { raise CanCan::AccessDenied }
     resource = CanCan::ControllerResource.new(@controller, :category, :parent => true)
     lambda { resource.authorize_resource }.should raise_error(CanCan::AccessDenied)
   end
 
   it "should perform authorization using controller action and loaded model" do
-    @params[:action] = "show"
+    @params.merge!(:action => "show", :id => 123)
     @controller.instance_variable_set(:@project, :some_project)
     stub(@controller).authorize!(:show, :some_project) { raise CanCan::AccessDenied }
     resource = CanCan::ControllerResource.new(@controller)
@@ -118,27 +118,36 @@ describe CanCan::ControllerResource do
   end
 
   it "should perform authorization using controller action and non loaded model" do
-    @params[:action] = "show"
+    @params.merge!(:action => "show", :id => 123)
     stub(@controller).authorize!(:show, Project) { 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"
+    @params.merge!(:action => "show", :id => 123)
     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
+  it "should not build a single resource when on custom collection action even with id" do
-    @params[:action] = "sort"
+    @params.merge!(:action => "sort", :id => 123)
     resource = CanCan::ControllerResource.new(@controller, :collection => [:sort, :list])
     resource.load_resource
     @controller.instance_variable_get(:@project).should be_nil
   end
 
+  it "should load a collection resource when on custom action with no id param" do
+    stub(Project).accessible_by(@ability, :sort) { :found_projects }
+    @params[:action] = "sort"
+    resource = CanCan::ControllerResource.new(@controller)
+    resource.load_resource
+    @controller.instance_variable_get(:@project).should be_nil
+    @controller.instance_variable_get(:@projects).should == :found_projects
+  end
+
   it "should build a resource when on custom new action even when params[:id] exists" do
     @params.merge!(:action => "build", :id => 123)
     stub(Project).new { :some_project }
@@ -226,7 +235,10 @@ describe CanCan::ControllerResource do
     resource = CanCan::ControllerResource.new(@controller, :through => :category)
     lambda {
       resource.load_resource
-    }.should raise_error(CanCan::AccessDenied)
+    }.should raise_error(CanCan::AccessDenied) { |exception|
+      exception.action.should == :show
+      exception.subject.should == Project
+    }
     @controller.instance_variable_get(:@project).should be_nil
   end
 
@@ -249,8 +261,8 @@ describe CanCan::ControllerResource do
     @controller.instance_variable_get(:@project).should == :some_project
   end
 
-  it "should find record through has_one association with :singleton option" do
+  it "should find record through has_one association with :singleton option without id param" do
-    @params.merge!(:action => "show")
+    @params.merge!(:action => "show", :id => nil)
     category = Object.new
     @controller.instance_variable_set(:@category, category)
     stub(category).project { :some_project }
@@ -259,14 +271,14 @@ describe CanCan::ControllerResource do
     @controller.instance_variable_get(:@project).should == :some_project
   end
 
-  it "should build record through has_one association with :singleton option" do
+  it "should not build record through has_one association with :singleton option because it can cause it to delete it in the database" do
     @params.merge!(:action => "create", :project => {:name => "foobar"})
-    category = Object.new
+    category = Category.new
     @controller.instance_variable_set(:@category, category)
-    stub(category).build_project { |attributes| Project.new(attributes) }
     resource = CanCan::ControllerResource.new(@controller, :through => :category, :singleton => true)
     resource.load_resource
     @controller.instance_variable_get(:@project).name.should == "foobar"
+    @controller.instance_variable_get(:@project).category.should == category
   end
 
   it "should find record through has_one association with :singleton and :shallow options" do
@@ -284,10 +296,10 @@ describe CanCan::ControllerResource do
     @controller.instance_variable_get(:@project).name.should == "foobar"
   end
 
-  it "should only authorize :read action on parent resource" do
+  it "should only authorize :show action on parent resource" do
     project = Project.create!
     @params.merge!(:action => "new", :project_id => project.id)
-    stub(@controller).authorize!(:read, project) { raise CanCan::AccessDenied }
+    stub(@controller).authorize!(:show, project) { raise CanCan::AccessDenied }
     resource = CanCan::ControllerResource.new(@controller, :project, :parent => true)
     lambda { resource.load_and_authorize_resource }.should raise_error(CanCan::AccessDenied)
   end

spec/cancan/inherited_resource_spec.rb

@@ -12,7 +12,7 @@ describe CanCan::InheritedResource do
   end
 
   it "show should load resource through @controller.resource" do
-    @params[:action] = "show"
+    @params.merge!(:action => "show", :id => 123)
     stub(@controller).resource { :project_resource }
     CanCan::InheritedResource.new(@controller).load_resource
     @controller.instance_variable_get(:@project).should == :project_resource
@@ -25,16 +25,16 @@ describe CanCan::InheritedResource do
     @controller.instance_variable_get(:@project).should == :project_resource
   end
 
-  it "index should load through @controller.parent when parent" do
+  it "index should load through @controller.association_chain when parent" do
     @params[:action] = "index"
-    stub(@controller).parent { :project_resource }
+    stub(@controller).association_chain { @controller.instance_variable_set(:@project, :project_resource) }
     CanCan::InheritedResource.new(@controller, :parent => true).load_resource
     @controller.instance_variable_get(:@project).should == :project_resource
   end
 
   it "index should load through @controller.end_of_association_chain" do
     @params[:action] = "index"
-    stub(Project).accessible_by(@ability) { :projects }
+    stub(Project).accessible_by(@ability, :index) { :projects }
     stub(@controller).end_of_association_chain { Project }
     CanCan::InheritedResource.new(@controller).load_resource
     @controller.instance_variable_get(:@projects).should == :projects

spec/cancan/model_adapters/active_record_adapter_spec.rb

@@ -8,12 +8,25 @@ if ENV["MODEL_ADAPTER"].nil? || ENV["MODEL_ADAPTER"] == "active_record"
   ActiveRecord::Base.establish_connection(:adapter => "sqlite3", :database => ":memory:")
 
   describe CanCan::ModelAdapters::ActiveRecordAdapter do
-    with_model :article do
+    with_model :category do
       table do |t|
-        t.boolean "published"
+        t.boolean "visible"
-        t.boolean "secret"
       end
       model do
+        has_many :articles
+      end
+    end
+
+    with_model :article do
+      table do |t|
+        t.string  "name"
+        t.boolean "published"
+        t.boolean "secret"
+        t.integer "priority"
+        t.integer "category_id"
+      end
+      model do
+        belongs_to :category
         has_many :comments
       end
     end
@@ -88,14 +101,45 @@ if ENV["MODEL_ADAPTER"].nil? || ENV["MODEL_ADAPTER"] == "active_record"
       Comment.accessible_by(@ability).should == [comment1]
     end
 
+    it "should only read comments for visible categories through articles" do
+      @ability.can :read, Comment, :article => { :category => { :visible => true } }
+      comment1 = Comment.create!(:article => Article.create!(:category => Category.create!(:visible => true)))
+      comment2 = Comment.create!(:article => Article.create!(:category => Category.create!(:visible => false)))
+      Comment.accessible_by(@ability).should == [comment1]
+    end
+
     it "should allow conditions in SQL and merge with hash conditions" do
       @ability.can :read, Article, :published => true
       @ability.can :read, Article, ["secret=?", true]
       article1 = Article.create!(:published => true, :secret => false)
+      article2 = Article.create!(:published => true, :secret => true)
+      article3 = Article.create!(:published => false, :secret => true)
       article4 = Article.create!(:published => false, :secret => false)
+      Article.accessible_by(@ability).should == [article1, article2, article3]
+    end
+
+    it "should allow a scope for conditions" do
+      @ability.can :read, Article, Article.where(:secret => true)
+      article1 = Article.create!(:secret => true)
+      article2 = Article.create!(:secret => false)
       Article.accessible_by(@ability).should == [article1]
     end
 
+    it "should fetch only associated records when using with a scope for conditions" do
+      @ability.can :read, Article, Article.where(:secret => true)
+      category1 = Category.create!(:visible => false)
+      category2 = Category.create!(:visible => true)
+      article1 = Article.create!(:secret => true, :category => category1)
+      article2 = Article.create!(:secret => true, :category => category2)
+      category1.articles.accessible_by(@ability).should == [article1]
+    end    
+
+    it "should raise an exception when trying to merge scope with other conditions" do
+      @ability.can :read, Article, :published => true
+      @ability.can :read, Article, Article.where(:secret => true)
+      lambda { Article.accessible_by(@ability) }.should raise_error(CanCan::Error, "Unable to merge an Active Record scope with other conditions. Instead use a hash or SQL for read Article ability.")
+    end
+
     it "should not allow to fetch records when ability with just block present" do
       @ability.can :read, Article do
         false
@@ -181,5 +225,49 @@ if ENV["MODEL_ADAPTER"].nil? || ENV["MODEL_ADAPTER"] == "active_record"
       @ability.can :read, Article, :project => { :admin => true }
       @ability.model_adapter(Article, :read).joins.should == [:project]
     end
+
+    it "should restrict articles given a MetaWhere condition" do
+      @ability.can :read, Article, :priority.lt => 2
+      article1 = Article.create!(:priority => 1)
+      article2 = Article.create!(:priority => 3)
+      Article.accessible_by(@ability).should == [article1]
+      @ability.should be_able_to(:read, article1)
+      @ability.should_not be_able_to(:read, article2)
+    end
+
+    it "should match any MetaWhere condition" do
+      adapter = CanCan::ModelAdapters::ActiveRecordAdapter
+      article1 = Article.new(:priority => 1, :name => "Hello World")
+      adapter.matches_condition?(article1, :priority.eq, 1).should be_true
+      adapter.matches_condition?(article1, :priority.eq, 2).should be_false
+      adapter.matches_condition?(article1, :priority.eq_any, [1, 2]).should be_true
+      adapter.matches_condition?(article1, :priority.eq_any, [2, 3]).should be_false
+      adapter.matches_condition?(article1, :priority.eq_all, [1, 1]).should be_true
+      adapter.matches_condition?(article1, :priority.eq_all, [1, 2]).should be_false
+      adapter.matches_condition?(article1, :priority.ne, 2).should be_true
+      adapter.matches_condition?(article1, :priority.ne, 1).should be_false
+      adapter.matches_condition?(article1, :priority.in, [1, 2]).should be_true
+      adapter.matches_condition?(article1, :priority.in, [2, 3]).should be_false
+      adapter.matches_condition?(article1, :priority.nin, [2, 3]).should be_true
+      adapter.matches_condition?(article1, :priority.nin, [1, 2]).should be_false
+      adapter.matches_condition?(article1, :priority.lt, 2).should be_true
+      adapter.matches_condition?(article1, :priority.lt, 1).should be_false
+      adapter.matches_condition?(article1, :priority.lteq, 1).should be_true
+      adapter.matches_condition?(article1, :priority.lteq, 0).should be_false
+      adapter.matches_condition?(article1, :priority.gt, 0).should be_true
+      adapter.matches_condition?(article1, :priority.gt, 1).should be_false
+      adapter.matches_condition?(article1, :priority.gteq, 1).should be_true
+      adapter.matches_condition?(article1, :priority.gteq, 2).should be_false
+      adapter.matches_condition?(article1, :name.like, "%ello worl%").should be_true
+      adapter.matches_condition?(article1, :name.like, "hello world").should be_true
+      adapter.matches_condition?(article1, :name.like, "hello%").should be_true
+      adapter.matches_condition?(article1, :name.like, "h%d").should be_true
+      adapter.matches_condition?(article1, :name.like, "%helo%").should be_false
+      adapter.matches_condition?(article1, :name.like, "hello").should be_false
+      adapter.matches_condition?(article1, :name.like, "hello.world").should be_false
+      # For some reason this is reporting "The not_matches MetaWhere condition is not supported."
+      # adapter.matches_condition?(article1, :name.nlike, "%helo%").should be_true
+      # adapter.matches_condition?(article1, :name.nlike, "%ello worl%").should be_false
+    end
   end
 end

spec/cancan/model_adapters/data_mapper_adapter_spec.rb

@@ -65,7 +65,6 @@ if ENV["MODEL_ADAPTER"] == "data_mapper"
     end
 
     it "should fetch only the articles that are published and not secret" do
-      pending "the `cannot` may require some custom SQL, maybe abstract out from Active Record adapter"
       @ability.can :read, Article, :published => true
       @ability.cannot :read, Article, :secret => true
       article1 = Article.create(:published => true, :secret => false)

spec/cancan/model_adapters/mongoid_adapter_spec.rb

@@ -42,6 +42,15 @@ if ENV["MODEL_ADAPTER"] == "mongoid"
         @ability.should be_able_to(:read, model)
       end
 
+      it "should be able to read hashes when field is array" do
+        one_to_three = MongoidProject.create(:numbers => ['one', 'two', 'three'])
+        two_to_five  = MongoidProject.create(:numbers => ['two', 'three', 'four', 'five'])
+
+        @ability.can :foo, MongoidProject, :numbers => 'one'
+        @ability.should be_able_to(:foo, one_to_three)
+        @ability.should_not be_able_to(:foo, two_to_five)
+      end
+
       it "should return [] when no ability is defined so no records are found" do
         MongoidProject.create(:title => 'Sir')
         MongoidProject.create(:title => 'Lord')
@@ -56,7 +65,16 @@ if ENV["MODEL_ADAPTER"] == "mongoid"
         lord  = MongoidProject.create(:title => 'Lord')
         dude  = MongoidProject.create(:title => 'Dude')
 
-        MongoidProject.accessible_by(@ability, :read).should == [sir]
+        MongoidProject.accessible_by(@ability, :read).entries.should == [sir]
+      end
+
+      it "should be able to mix empty conditions and hashes" do
+        @ability.can :read, MongoidProject
+        @ability.can :read, MongoidProject, :title => 'Sir'
+        sir  = MongoidProject.create(:title => 'Sir')
+        lord = MongoidProject.create(:title => 'Lord')
+
+        MongoidProject.accessible_by(@ability, :read).count.should == 2
       end
 
       it "should return everything when the defined ability is manage all" do
@@ -68,6 +86,14 @@ if ENV["MODEL_ADAPTER"] == "mongoid"
         MongoidProject.accessible_by(@ability, :read).entries.should == [sir, lord, dude]
       end
 
+      it "should allow a scope for conditions" do
+        @ability.can :read, MongoidProject, MongoidProject.where(:title => 'Sir')
+        sir   = MongoidProject.create(:title => 'Sir')
+        lord  = MongoidProject.create(:title => 'Lord')
+        dude  = MongoidProject.create(:title => 'Dude')
+
+        MongoidProject.accessible_by(@ability, :read).entries.should == [sir]
+      end
 
       describe "Mongoid::Criteria where clause Symbol extensions using MongoDB expressions" do
         it "should handle :field.in" do
@@ -155,6 +181,23 @@ if ENV["MODEL_ADAPTER"] == "mongoid"
         MongoidProject.accessible_by(@ability, :read).entries.first.should == obj
       end
       
+      it "should exclude from the result if set to cannot" do
+        obj = MongoidProject.create(:bar => 1)
+        obj2 = MongoidProject.create(:bar => 2)
+        @ability.can :read, MongoidProject
+        @ability.cannot :read, MongoidProject, :bar => 2
+        MongoidProject.accessible_by(@ability, :read).entries.should == [obj]
+      end
+
+      it "should combine the rules" do
+        obj = MongoidProject.create(:bar => 1)
+        obj2 = MongoidProject.create(:bar => 2)
+        obj3 = MongoidProject.create(:bar => 3)
+        @ability.can :read, MongoidProject, :bar => 1
+        @ability.can :read, MongoidProject, :bar => 2
+        MongoidProject.accessible_by(@ability, :read).entries.should =~ [obj, obj2]
+      end
+      
       it "should not allow to fetch records when ability with just block present" do
         @ability.can :read, MongoidProject do
           false

spec/spec_helper.rb

@@ -29,4 +29,5 @@ end
 
 class Project < SuperModel::Base
   belongs_to :category
+  attr_accessor :category # why doesn't SuperModel do this automatically?
 end