added dependent option to should_belong_to [#108]

lib/shoulda/active_record/macros.rb

@@ -537,7 +537,7 @@ module Shoulda # :nodoc:
       #   should_belong_to :parent
       #
       def should_belong_to(*associations)
-        get_options!(associations)
+        dependent = get_options!(associations, :dependent)
         klass = model_class
         associations.each do |association|
           should "belong_to #{association}" do
@@ -550,6 +550,12 @@ module Shoulda # :nodoc:
               fk = reflection.options[:foreign_key] || reflection.primary_key_name
               assert klass.column_names.include?(fk.to_s), "#{klass.name} does not have a #{fk} foreign key."
             end
+
+            if dependent
+              assert_equal dependent.to_s,
+                           reflection.options[:dependent].to_s,
+                           "#{association} should have #{dependent} dependency"
+            end
           end
         end
       end

test/rails_root/app/models/pets/dog.rb

@@ -1,7 +1,7 @@
 module Pets
   class Dog < ActiveRecord::Base
     belongs_to :user, :foreign_key => :owner_id
-    belongs_to :address
+    belongs_to :address, :dependent => :destroy
     has_many :treats
     has_and_belongs_to_many :fleas, :join_table => :fleas
     validates_presence_of :treats, :fleas

test/unit/dog_test.rb

@@ -2,7 +2,7 @@ require File.dirname(__FILE__) + '/../test_helper'
 
 class Pets::DogTest < Test::Unit::TestCase
   should_belong_to :user
-  should_belong_to :address
+  should_belong_to :address, :dependent => :destroy
   should_have_many :treats
   should_have_and_belong_to_many :fleas
   should_require_attributes :treats, :fleas