Add Model#delete instance method, similar to Model.delete class method. [#1086 state:resolved]

Signed-off-by: Pratik Naik <pratiknaik@gmail.com>

activerecord/CHANGELOG

@@ -1,5 +1,7 @@
 *Edge*
 
+* Add Model#delete instance method, similar to Model.delete class method. #1086 [Hongli Lai]
+
 * MySQL: cope with quirky default values for not-null text columns.  #1043 [Frederick Cheung]
 
 * Multiparameter attributes skip time zone conversion for time-only columns [#1030 state:resolved] [Geoff Buesing]

activerecord/lib/active_record/associations.rb

@@ -1470,7 +1470,7 @@ module ActiveRecord
                 method_name = "has_one_dependent_delete_for_#{reflection.name}".to_sym
                 define_method(method_name) do
                   association = send(reflection.name)
-                  association.class.delete(association.id) unless association.nil?
+                  association.delete unless association.nil?
                 end
                 before_destroy method_name
               when :nullify
@@ -1500,7 +1500,7 @@ module ActiveRecord
                 method_name = "belongs_to_dependent_delete_for_#{reflection.name}".to_sym
                 define_method(method_name) do
                   association = send(reflection.name)
-                  association.class.delete(association.id) unless association.nil?
+                  association.delete unless association.nil?
                 end
                 before_destroy method_name
               else

activerecord/lib/active_record/base.rb

@@ -2304,6 +2304,16 @@ module ActiveRecord #:nodoc:
         create_or_update || raise(RecordNotSaved)
       end
 
+      # Deletes the record in the database and freezes this instance to reflect that no changes should
+      # be made (since they can't be persisted).
+      #
+      # Unlike #destroy, this method doesn't run any +before_delete+ and +after_delete+
+      # callbacks, nor will it enforce any association +:dependent+ rules.
+      def delete
+        self.class.delete(id) unless new_record?
+        freeze
+      end
+
       # Deletes the record in the database and freezes this instance to reflect that no changes should
       # be made (since they can't be persisted).
       def destroy

activerecord/test/cases/base_test.rb

@@ -472,6 +472,18 @@ class BasicsTest < ActiveRecord::TestCase
     assert topic.instance_variable_get("@custom_approved")
   end
 
+  def test_delete
+    topic = Topic.find(1)
+    assert_equal topic, topic.delete, 'topic.delete did not return self'
+    assert topic.frozen?, 'topic not frozen after delete'
+    assert_raise(ActiveRecord::RecordNotFound) { Topic.find(topic.id) }
+  end
+
+  def test_delete_doesnt_run_callbacks
+    Topic.find(1).delete
+    assert_not_nil Topic.find(2)
+  end
+
   def test_destroy
     topic = Topic.find(1)
     assert_equal topic, topic.destroy, 'topic.destroy did not return self'
@@ -820,6 +832,20 @@ class BasicsTest < ActiveRecord::TestCase
     assert_equal [ Topic.find(1) ], [ Topic.find(2).topic ] & [ Topic.find(1) ]
   end
 
+  def test_delete_new_record
+    client = Client.new
+    client.delete
+    assert client.frozen?
+  end
+
+  def test_delete_record_with_associations
+    client = Client.find(3)
+    client.delete
+    assert client.frozen?
+    assert_kind_of Firm, client.firm
+    assert_raises(ActiveSupport::FrozenObjectError) { client.name = "something else" }
+  end
+
   def test_destroy_new_record
     client = Client.new
     client.destroy