From f7ac04c2cf2cb8ae4756cc9b5e42306af95028c6 Mon Sep 17 00:00:00 2001
From: Emilio Tagua <miloops@gmail.com>
Date: Wed, 9 Dec 2009 16:47:26 -0300
Subject: [PATCH] ActiveRecord::Relation#to_a should not load records each time is called.

---
 activerecord/lib/active_record/base.rb     |    2 ++
 activerecord/lib/active_record/relation.rb |    2 ++
 activerecord/test/cases/relations_test.rb  |   10 +++++++++-
 3 files changed, 13 insertions(+), 1 deletions(-)

diff --git a/activerecord/lib/active_record/base.rb b/activerecord/lib/active_record/base.rb
index 321bba4..62cece8 100755
--- a/activerecord/lib/active_record/base.rb
+++ b/activerecord/lib/active_record/base.rb
@@ -681,6 +681,8 @@ module ActiveRecord #:nodoc:
             end
           end
         end
+
+        relation.unmemoize_all
         relation
       end
 
diff --git a/activerecord/lib/active_record/relation.rb b/activerecord/lib/active_record/relation.rb
index 5f0eec7..fb44efc 100644
--- a/activerecord/lib/active_record/relation.rb
+++ b/activerecord/lib/active_record/relation.rb
@@ -1,5 +1,6 @@
 module ActiveRecord
   class Relation
+    extend ActiveSupport::Memoizable
     delegate :to_sql, :to => :relation
     delegate :length, :collect, :find, :map, :each, :to => :to_a
     attr_reader :relation, :klass
@@ -50,6 +51,7 @@ module ActiveRecord
 
       records
     end
+    memoize :to_a
 
     def first
       @relation = @relation.take(1)
diff --git a/activerecord/test/cases/relations_test.rb b/activerecord/test/cases/relations_test.rb
index 1a2c803..39f204e 100644
--- a/activerecord/test/cases/relations_test.rb
+++ b/activerecord/test/cases/relations_test.rb
@@ -146,5 +146,13 @@ class RelationTest < ActiveRecord::TestCase
     post = posts.find { |p| p.id == 1 }
     assert_equal Post.find(1).last_comment, post.last_comment
   end
-end
 
+  def test_should_memoize_records
+    @posts = Post.all
+    assert_queries(1) do
+      2.times do
+        @posts.to_a
+      end
+    end
+  end
+end
-- 
1.6.5