Ensures destroy and restore operations are wrapped in a transaction that is rolled back when the callback chain is halted

lib/destroyed_at.rb

@@ -2,6 +2,7 @@
 require 'destroyed_at/belongs_to_association'
 require 'destroyed_at/has_many_association'
 require 'destroyed_at/has_one_association'
+require 'destroyed_at/record_not_restored'
 require 'destroyed_at/mapper'
 
 module DestroyedAt
@@ -39,12 +40,14 @@ def destroyed(time = nil)
 
   # Set an object's destroyed_at time.
   def destroy(timestamp = nil)
-    timestamp ||= @marked_for_destruction_at || current_time_from_proper_timezone
-    raw_write_attribute(:destroyed_at, timestamp)
-    run_callbacks(:destroy) do
-      destroy_associations
-      self.class.unscoped.where(self.class.primary_key => id).update_all(destroyed_at: timestamp)
-      @destroyed = true
+    with_transaction_returning_status do
+      timestamp ||= @marked_for_destruction_at || current_time_from_proper_timezone
+      raw_write_attribute(:destroyed_at, timestamp)
+      run_callbacks(:destroy) do
+        destroy_associations
+        self.class.unscoped.where(self.class.primary_key => id).update_all(destroyed_at: timestamp)
+        @destroyed = true
+      end
     end
   end
 
@@ -56,16 +59,22 @@ def mark_for_destruction(timestamp = nil)
 
   # Set an object's destroyed_at time to nil.
   def restore
-    state = nil
-    run_callbacks(:restore) do
-      if state = (self.class.unscoped.where(self.class.primary_key => id).update_all(destroyed_at: nil) == 1)
-        _restore_associations
-        raw_write_attribute(:destroyed_at, nil)
-        @destroyed = false
-        true
+    with_transaction_returning_status do
+      state = nil
+      run_callbacks(:restore) do
+        if state = (self.class.unscoped.where(self.class.primary_key => id).update_all(destroyed_at: nil) == 1)
+          _restore_associations
+          raw_write_attribute(:destroyed_at, nil)
+          @destroyed = false
+          true
+        end
       end
+      state
     end
-    state
+  end
+
+  def restore!
+    restore || raise(RecordNotRestored, self)
   end
 
   def persisted?

lib/destroyed_at/record_not_restored.rb

@@ -0,0 +1,7 @@
+class DestroyedAt::RecordNotRestored < ActiveRecord::ActiveRecordError
+  attr_reader :record
+  def initialize(record)
+    @record = record
+    super()
+  end
+end

test/destroyed_at_test.rb

@@ -96,6 +96,53 @@
     comment.destroyed_at.must_equal datetime
   end
 
+  it 'rollsback the transaction when destroying fails' do
+    pet_type = PetType.create(name: 'Cat')
+    pet = Pet.create(pet_type: pet_type)
+
+    Pet.count.must_equal 1
+    PetType.count.must_equal 1
+
+    pet_type.destroy
+
+    Pet.count.must_equal 1
+    PetType.count.must_equal 1
+  end
+
+  it 'runs the after_commit callbacks when successful' do
+    pet_type = PetType.create(name: 'Cat')
+
+    Pet.count.must_equal 0
+    PetType.count.must_equal 1
+
+    pet_type.reset_transaction_state_callback_observers
+
+    pet_type.after_commit_called?.must_equal false
+    pet_type.after_rollback_called?.must_equal false
+
+    pet_type.destroy
+
+    pet_type.after_commit_called?.must_equal true
+    pet_type.after_rollback_called?.must_equal false
+  end
+
+  it 'runs the after_rollback callbacks when failed' do
+    pet_type = PetType.create(name: 'Cat')
+    pet = Pet.create(pet_type: pet_type)
+
+    Pet.count.must_equal 1
+    PetType.count.must_equal 1
+
+    pet_type.reset_transaction_state_callback_observers
+
+    pet_type.after_commit_called?.must_equal false
+    pet_type.after_rollback_called?.must_equal false
+
+    pet_type.destroy
+
+    pet_type.after_commit_called?.must_equal false
+    pet_type.after_rollback_called?.must_equal true
+  end
 end
 
 describe 'restoring an activerecord instance' do
@@ -192,6 +239,30 @@
     post.comments.wont_include comment_1
     post.comments.must_include comment_2
   end
+
+  it 'rollsback the transaction when restoring fails' do
+    pet_type = PetType.create(name: 'Cat')
+
+    PetType.count.must_equal 1
+    pet_type.destroy
+
+    Pet.count.must_equal 0
+    PetType.count.must_equal 0
+    pet_type.restore
+
+    Pet.count.must_equal 0
+    PetType.count.must_equal 0
+  end
+
+  it 'raises DestroyedAt::RecordNotRestored if the record cannot be restored using #restore!' do
+    pet_type = PetType.create(name: 'Cat')
+
+    PetType.count.must_equal 1
+    pet_type.destroy
+
+    PetType.count.must_equal 0
+    assert_raises(DestroyedAt::RecordNotRestored) { pet_type.restore! }
+  end
 end
 
 describe 'deleting a record' do

test/test_helper.rb

@@ -37,7 +37,8 @@ class << self
 ActiveRecord::Base.connection.execute(%{CREATE TABLE images (id INTEGER PRIMARY KEY, post_id INTEGER);})
 ActiveRecord::Base.connection.execute(%{CREATE TABLE posts (id INTEGER PRIMARY KEY, author_id INTEGER, destroyed_at DATETIME);})
 ActiveRecord::Base.connection.execute(%{CREATE TABLE people (id INTEGER PRIMARY KEY);})
-ActiveRecord::Base.connection.execute(%{CREATE TABLE pets (id INTEGER PRIMARY KEY, person_id INTEGER);})
+ActiveRecord::Base.connection.execute(%{CREATE TABLE pet_types (id INTEGER PRIMARY KEY, name TEXT, destroyed_at DATETIME);})
+ActiveRecord::Base.connection.execute(%{CREATE TABLE pets (id INTEGER PRIMARY KEY, person_id INTEGER, pet_type_id INTEGER);})
 ActiveRecord::Base.connection.execute(%{CREATE TABLE likes (id INTEGER PRIMARY KEY, likeable_id INTEGER, likeable_type TEXT, destroyed_at DATETIME);})
 
 class Author < ActiveRecord::Base
@@ -52,6 +53,40 @@ class Person < ActiveRecord::Base
 
 class Pet < ActiveRecord::Base
   belongs_to :person
+  belongs_to :pet_type
+end
+
+class PetType < ActiveRecord::Base
+  include DestroyedAt
+  has_many :pets, dependent: :restrict_with_error
+
+  after_restore do
+    Pet.create!(pet_type: self) # mutate the database
+
+    raise ActiveRecord::Rollback # halt the callback chain
+  end
+
+  # Observe the transaction state callbacks
+  def reset_transaction_state_callback_observers
+    @after_commit_called = false
+    @after_rollback_called = false
+  end
+
+  after_commit do
+    @after_commit_called = true
+  end
+
+  def after_commit_called?
+    !!@after_commit_called
+  end
+
+  after_rollback do
+    @after_rollback_called = true
+  end
+
+  def after_rollback_called?
+    !!@after_rollback_called
+  end
 end
 
 class Avatar < ActiveRecord::Base