has_one supports the :dependent => :delete option which skips the typical callback chain and deletes the associated object directly from the database. Closes #5927.

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@4848 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

activerecord/CHANGELOG

@@ -1,5 +1,7 @@
 *SVN*
 
+* has_one supports the :dependent => :delete option which skips the typical callback chain and deletes the associated object directly from the database.  #5927 [Chris Mear, Jonathan Viney]
+
 * Nested subclasses are not prefixed with the parent class' table_name since they should always use the base class' table_name.  #5911 [Jonathan Viney]
 
 * SQLServer: work around bug where some unambiguous date formats are not correctly identified if the session language is set to german.  #5894 [Tom Ward, kruth@bfpi]

activerecord/lib/active_record/associations.rb

@@ -570,8 +570,9 @@ module ActiveRecord
       #   sql fragment, such as "rank = 5".
       # * <tt>:order</tt>       - specify the order from which the associated object will be picked at the top. Specified as
       #    an "ORDER BY" sql fragment, such as "last_name, first_name DESC"
-      # * <tt>:dependent</tt>   - if set to :destroy (or true) all the associated objects are destroyed when this object is. Also,
-      #   association is assigned.
+      # * <tt>:dependent</tt>   - if set to :destroy (or true) the associated object is destroyed when this object is. If set to
+      #   :delete the associated object is deleted *without* calling its destroy method. If set to :nullify the associated
+      #   object's foreign key is set to NULL. Also, association is assigned.
       # * <tt>:foreign_key</tt> - specify the foreign key used for the association. By default this is guessed to be the name
       #   of this class in lower-case and "_id" suffixed. So a +Person+ class that makes a has_one association will use "person_id"
       #   as the default foreign_key.
@@ -1020,12 +1021,14 @@ module ActiveRecord
           case reflection.options[:dependent]
             when :destroy, true
               module_eval "before_destroy '#{reflection.name}.destroy unless #{reflection.name}.nil?'"
+            when :delete
+              module_eval "before_destroy '#{reflection.class_name}.delete(#{reflection.name}.id) unless #{reflection.name}.nil?'"
             when :nullify
               module_eval "before_destroy '#{reflection.name}.update_attribute(\"#{reflection.primary_key_name}\", nil)'"
             when nil, false
               # pass
             else
-              raise ArgumentError, "The :dependent option expects either :destroy or :nullify."
+              raise ArgumentError, "The :dependent option expects either :destroy, :delete or :nullify."
           end
         end
         

activerecord/test/associations_test.rb

@@ -91,6 +91,10 @@ end
 class HasOneAssociationsTest < Test::Unit::TestCase
   fixtures :accounts, :companies, :developers, :projects, :developers_projects
   
+  def setup
+    Account.destroyed_account_ids.clear
+  end
+  
   def test_has_one
     assert_equal companies(:first_firm).account, Account.find(1)
     assert_equal Account.find(1).credit_limit, companies(:first_firm).account.credit_limit
@@ -168,8 +172,22 @@ class HasOneAssociationsTest < Test::Unit::TestCase
     num_accounts = Account.count
     firm = Firm.find(1)
     assert !firm.account.nil?
+    account_id = firm.account.id
+    assert_equal [], Account.destroyed_account_ids[firm.id]
     firm.destroy                
     assert_equal num_accounts - 1, Account.count
+    assert_equal [account_id], Account.destroyed_account_ids[firm.id]
+  end
+  
+  def test_exclusive_dependence
+    num_accounts = Account.count
+    firm = ExclusivelyDependentFirm.find(9)
+    assert !firm.account.nil?
+    account_id = firm.account.id
+    assert_equal [], Account.destroyed_account_ids[firm.id]
+    firm.destroy
+    assert_equal num_accounts - 1, Account.count
+    assert_equal [], Account.destroyed_account_ids[firm.id]
   end
 
   def test_succesful_build_association

activerecord/test/calculations_test.rb

@@ -8,7 +8,7 @@ class CalculationsTest < Test::Unit::TestCase
   fixtures :companies, :accounts, :topics
 
   def test_should_sum_field
-    assert_equal 265, Account.sum(:credit_limit)
+    assert_equal 318, Account.sum(:credit_limit)
   end
 
   def test_should_average_field
@@ -49,13 +49,13 @@ class CalculationsTest < Test::Unit::TestCase
 
   def test_should_order_by_grouped_field
     c = Account.sum(:credit_limit, :group => :firm_id, :order => "firm_id")
-    assert_equal [1, 2, 6], c.keys.compact
+    assert_equal [1, 2, 6, 9], c.keys.compact
   end
 
   def test_should_order_by_calculation
     c = Account.sum(:credit_limit, :group => :firm_id, :order => "sum_credit_limit desc, firm_id")
-    assert_equal [105, 60, 50, 50], c.keys.collect { |k| c[k] }
-    assert_equal [6, 2, 1], c.keys.compact
+    assert_equal [105, 60, 53, 50, 50], c.keys.collect { |k| c[k] }
+    assert_equal [6, 2, 9, 1], c.keys.compact
   end
 
   def test_should_limit_calculation
@@ -114,8 +114,8 @@ class CalculationsTest < Test::Unit::TestCase
   end
   
   def test_should_calculate_with_invalid_field
-    assert_equal 5, Account.calculate(:count, '*')
-    assert_equal 5, Account.calculate(:count, :all)
+    assert_equal 6, Account.calculate(:count, '*')
+    assert_equal 6, Account.calculate(:count, :all)
   end
   
   def test_should_calculate_grouped_with_invalid_field
@@ -193,7 +193,7 @@ class CalculationsTest < Test::Unit::TestCase
   end
 
   def test_should_count_selected_field_with_include
-    assert_equal 5, Account.count(:distinct => true, :include => :firm)
-    assert_equal 3, Account.count(:distinct => true, :include => :firm, :select => :credit_limit)
+    assert_equal 6, Account.count(:distinct => true, :include => :firm)
+    assert_equal 4, Account.count(:distinct => true, :include => :firm, :select => :credit_limit)
   end
 end

activerecord/test/finder_test.rb

@@ -454,8 +454,8 @@ class FinderTest < Test::Unit::TestCase
   end
 
   def test_select_values
-    assert_equal ["1","2","3","4","5","6","7","8"], Company.connection.select_values("SELECT id FROM companies ORDER BY id").map! { |i| i.to_s }
-    assert_equal ["37signals","Summit","Microsoft", "Flamboyant Software", "Ex Nihilo", "RailsCore", "Leetsoft", "Jadedpixel"], Company.connection.select_values("SELECT name FROM companies ORDER BY id")
+    assert_equal ["1","2","3","4","5","6","7","8","9"], Company.connection.select_values("SELECT id FROM companies ORDER BY id").map! { |i| i.to_s }
+    assert_equal ["37signals","Summit","Microsoft", "Flamboyant Software", "Ex Nihilo", "RailsCore", "Leetsoft", "Jadedpixel", "Odegy"], Company.connection.select_values("SELECT name FROM companies ORDER BY id")
   end
 
   protected

activerecord/test/fixtures/accounts.yml

@@ -20,4 +20,9 @@ last_account:
 rails_core_account_2:
   id: 5
   firm_id: 6
-  credit_limit: 55
+  credit_limit: 55
+
+odegy_account:
+  id: 6
+  firm_id: 9
+  credit_limit: 53

activerecord/test/fixtures/companies.yml

@@ -47,4 +47,9 @@ leetsoft:
 jadedpixel:
   id: 8 
   name: Jadedpixel
-  client_of: 6
+  client_of: 6
+
+odegy:
+  id: 9
+  name: Odegy
+  type: ExclusivelyDependentFirm

activerecord/test/fixtures/company.rb

@@ -42,6 +42,9 @@ class DependentFirm < Company
   has_many :companies, :foreign_key => 'client_of', :order => "id", :dependent => :nullify
 end
 
+class ExclusivelyDependentFirm < Company
+  has_one :account, :foreign_key => "firm_id", :dependent => :delete
+end
 
 class Client < Company
   belongs_to :firm, :foreign_key => "client_of"
@@ -83,6 +86,18 @@ end
 class Account < ActiveRecord::Base
   belongs_to :firm
   
+  def self.destroyed_account_ids
+    @destroyed_account_ids ||= Hash.new { |h,k| h[k] = [] }
+  end
+
+  before_destroy do |account|
+    if account.firm
+      Account.destroyed_account_ids[account.firm.id] << account.id
+    end
+    true
+  end
+  
+  
   protected
     def validate
       errors.add_on_empty "credit_limit"

activerecord/test/inheritance_test.rb

@@ -58,7 +58,7 @@ class InheritanceTest < Test::Unit::TestCase
   end
 
   def test_inheritance_condition
-    assert_equal 8, Company.count
+    assert_equal 9, Company.count
     assert_equal 2, Firm.count
     assert_equal 3, Client.count
   end