Rails Lighthouse ticket #6555

delete_all_with_joins.diff

From bb70528d0cb386a06c82d0ee0dca2b941849fa96 Mon Sep 17 00:00:00 2001
From: Akira Matsuda <ronnie@dio.jp>
Date: Thu, 10 Mar 2011 18:15:33 +0900
Subject: [PATCH] make sure that delete_all works when chained with joins

---
 activerecord/lib/active_record/relation.rb  |    8 +++++++-
 activerecord/test/cases/persistence_test.rb |    8 ++++++++
 2 files changed, 15 insertions(+), 1 deletions(-)

diff --git a/activerecord/lib/active_record/relation.rb b/activerecord/lib/active_record/relation.rb
index 5af20bf..476fd92 100644
--- a/activerecord/lib/active_record/relation.rb
+++ b/activerecord/lib/active_record/relation.rb
@@ -311,7 +311,13 @@ module ActiveRecord
       if conditions
         where(conditions).delete_all
       else
-        statement = arel.compile_delete
+        statement = if joins_values.present?
+          pk = "#{@klass.connection.quote_table_name table_name}.#{primary_key}"
+          ids = select(pk)
+          unscoped { @klass.where("#{pk} in (#{ids.to_sql})").build_arel.compile_delete }
+        else
+          arel.compile_delete
+        end
         affected = @klass.connection.delete statement.to_sql
         reset
         affected
diff --git a/activerecord/test/cases/persistence_test.rb b/activerecord/test/cases/persistence_test.rb
index 8ca9d62..e1a815a 100644
--- a/activerecord/test/cases/persistence_test.rb
+++ b/activerecord/test/cases/persistence_test.rb
@@ -11,6 +11,8 @@ require 'models/project'
 require 'models/minimalistic'
 require 'models/warehouse_thing'
 require 'models/parrot'
+require 'models/pet'
+require 'models/toy'
 require 'models/minivan'
 require 'models/loose_person'
 require 'rexml/document'
@@ -56,6 +58,12 @@ class PersistencesTest < ActiveRecord::TestCase
     assert_equal Topic.count, Topic.delete_all
   end
 
+  def test_delete_all_with_joins
+    assert (count = Pet.joins(:toys).where(:toys => {:name => 'Bone'}).count) > 0
+
+    assert_equal count, Pet.joins(:toys).where(:toys => {:name => 'Bone'}).delete_all
+  end
+
   def test_update_by_condition
     Topic.update_all "content = 'bulk updated!'", ["approved = ?", true]
     assert_equal "Have a nice day", Topic.find(1).content
-- 
1.7.4.1