adding basic ability module

spec/cancan/ability_spec.rb

@@ -0,0 +1,40 @@
+require File.dirname(__FILE__) + '/../spec_helper'
+
+class Ability
+  include CanCan::Ability
+  can :read, :all
+  can :read, Symbol do |sym|
+    sym
+  end
+  can :preview, :all do |object_class, object|
+    [object_class, object]
+  end
+end
+
+describe CanCan::Ability do
+  before(:each) do
+    @ability = Ability.new
+  end
+  
+  it "should be able to :read anything" do
+    @ability.can?(:read, String).should be_true
+    @ability.can?(:read, 123).should be_true
+  end
+  
+  it "should not have permission to do something it doesn't know about" do
+    @ability.can?(:foodfight, String).should be_false
+  end
+  
+  it "should return what block returns on a can call" do
+    @ability.can?(:read, Symbol).should be_nil
+    @ability.can?(:read, :some_symbol).should == :some_symbol
+  end
+  
+  it "should pass class with object if :all objects are accepted" do
+    @ability.can?(:preview, 123).should == [Fixnum, 123]
+  end
+  
+  it "should pass class with no object if :all objects are accepted and class is passed directly" do
+    @ability.can?(:preview, Hash).should == [Hash, nil]
+  end
+end