gistfile1.diff

From b7894c95720d13ec7d955fb3675294db5aedf987 Mon Sep 17 00:00:00 2001
From: Luke Redpath <contact@lukeredpath.co.uk>
Date: Fri, 27 Feb 2009 17:35:41 +0000
Subject: [PATCH] Initial attempt at adding a :scope option to has_many :through.

This allows you to have has_many :through collections that go
through a named scope on your join model. This should make it
clearer: http://gist.github.com/71585
---
 activerecord/lib/active_record/associations.rb     |    3 ++-
 .../associations/has_many_through_association.rb   |   11 +++++++++++
 .../has_many_through_associations_test.rb          |   11 +++++++++++
 activerecord/test/models/post.rb                   |    2 ++
 activerecord/test/models/tagging.rb                |    2 ++
 activerecord/test/schema/schema.rb                 |    1 +
 6 files changed, 29 insertions(+), 1 deletions(-)

diff --git a/activerecord/lib/active_record/associations.rb b/activerecord/lib/active_record/associations.rb
index 6e88c89..7ab3a88 100755
--- a/activerecord/lib/active_record/associations.rb
+++ b/activerecord/lib/active_record/associations.rb
@@ -1462,7 +1462,8 @@ module ActiveRecord
           :finder_sql, :counter_sql,
           :before_add, :after_add, :before_remove, :after_remove,
           :extend, :readonly,
-          :validate
+          :validate, 
+          :scope
         ]
 
         def create_has_many_reflection(association_id, options, &extension)
diff --git a/activerecord/lib/active_record/associations/has_many_through_association.rb b/activerecord/lib/active_record/associations/has_many_through_association.rb
index d5d188a..b8f197f 100644
--- a/activerecord/lib/active_record/associations/has_many_through_association.rb
+++ b/activerecord/lib/active_record/associations/has_many_through_association.rb
@@ -125,8 +125,19 @@ module ActiveRecord
             "#{table_name}.#{attr} = #{value}"
           end
           conditions << sql_conditions if sql_conditions
+          conditions << through_scope_conditions if through_scope_conditions
           "(" + conditions.join(') AND (') + ")"
         end
+        
+        def through_scope_conditions
+          return unless @reflection.options[:scope]
+          if scope_proxy = @reflection.through_reflection.klass.send(@reflection.options[:scope])
+            scope_proxy.proxy_options[:conditions].inject([]) do |scope_conditions, (key, value)|
+              scope_conditions << "#{@reflection.through_reflection.quoted_table_name}.#{key} = #{value}"
+              scope_conditions
+            end
+          end
+        end
 
         def construct_from
           @reflection.quoted_table_name
diff --git a/activerecord/test/cases/associations/has_many_through_associations_test.rb b/activerecord/test/cases/associations/has_many_through_associations_test.rb
index 1e5d1a0..b9538f7 100644
--- a/activerecord/test/cases/associations/has_many_through_associations_test.rb
+++ b/activerecord/test/cases/associations/has_many_through_associations_test.rb
@@ -249,4 +249,15 @@ class HasManyThroughAssociationsTest < ActiveRecord::TestCase
     author.author_favorites.create(:favorite_author_id => 3)
     assert_equal post.author.author_favorites, post.author_favorites
   end
+  
+  def test_has_many_association_through_a_scoped_association
+    author = authors(:mary)
+    post = Post.create!(:author => author, :title => "TITLE", :body => "BODY")
+    tag_one = Tag.create!(:name => 'ruby')
+    tag_two = Tag.create!(:name => 'rails')
+    post.taggings.flagged.create(:tag => tag_one)
+    post.taggings.create(:tag => tag_two)
+    assert post.taggings.first.flagged?
+    assert_equal [tag_one], post.flagged_tags
+  end
 end
diff --git a/activerecord/test/models/post.rb b/activerecord/test/models/post.rb
index 374e536..ce665f2 100644
--- a/activerecord/test/models/post.rb
+++ b/activerecord/test/models/post.rb
@@ -58,6 +58,8 @@ class Post < ActiveRecord::Base
 
   has_many :invalid_taggings, :as => :taggable, :class_name => "Tagging", :conditions => 'taggings.id < 0'
   has_many :invalid_tags, :through => :invalid_taggings, :source => :tag
+  
+  has_many :flagged_tags, :through => :taggings, :source => :tag, :scope => :flagged
 
   has_many :categorizations, :foreign_key => :category_id
   has_many :authors, :through => :categorizations
diff --git a/activerecord/test/models/tagging.rb b/activerecord/test/models/tagging.rb
index a1fa1a9..3e04dc8 100644
--- a/activerecord/test/models/tagging.rb
+++ b/activerecord/test/models/tagging.rb
@@ -7,4 +7,6 @@ class Tagging < ActiveRecord::Base
   belongs_to :super_tag,   :class_name => 'Tag', :foreign_key => 'super_tag_id'
   belongs_to :invalid_tag, :class_name => 'Tag', :foreign_key => 'tag_id'
   belongs_to :taggable, :polymorphic => true, :counter_cache => true
+  
+  named_scope :flagged, :conditions => {:flagged => true}
 end
\ No newline at end of file
diff --git a/activerecord/test/schema/schema.rb b/activerecord/test/schema/schema.rb
index 74a8939..4610f67 100644
--- a/activerecord/test/schema/schema.rb
+++ b/activerecord/test/schema/schema.rb
@@ -414,6 +414,7 @@ ActiveRecord::Schema.define do
     t.column :super_tag_id, :integer
     t.column :taggable_type, :string
     t.column :taggable_id, :integer
+    t.column :flagged, :boolean
   end
 
   create_table :tags, :force => true do |t|
-- 
1.5.6.4