Add :recursive option on restore to restore associations

Fixes #91

lib/paranoia.rb

@@ -16,11 +16,11 @@ module Paranoia
     end
     alias :deleted :only_deleted
 
-    def restore(id)
+    def restore(id, opts = {})
       if id.is_a?(Array)
-        id.map { |one_id| restore(one_id) }
+        id.map { |one_id| restore(one_id, opts) }
       else
-        only_deleted.find(id).restore!
+        only_deleted.find(id).restore!(opts)
       end
     end
   end
@@ -52,8 +52,13 @@ module Paranoia
     delete_or_soft_delete
   end
 
-  def restore!
-    run_callbacks(:restore) { update_column paranoia_column, nil }
+  def restore!(opts = {})
+    ActiveRecord::Base.transaction do
+      run_callbacks(:restore) do
+        update_column paranoia_column, nil
+        restore_associated_records if opts[:recursive]
+      end
+    end
   end
 
   def destroyed?
@@ -78,6 +83,22 @@ module Paranoia
       touch(paranoia_column)
     end
   end
+
+  # restore associated records that have been soft deleted when
+  # we called #destroy
+  def restore_associated_records
+    destroyed_associations = self.class.reflect_on_all_associations.select do |association|
+      association.options[:dependent] == :destroy
+    end
+
+    destroyed_associations.each do |association|
+      association = send(association.name)
+
+      if association.paranoid?
+        association.only_deleted.each { |record| record.restore(:recursive => true) }
+      end
+    end
+  end
 end
 
 class ActiveRecord::Base

test/paranoia_test.rb

@@ -18,6 +18,7 @@ ActiveRecord::Base.connection.execute 'CREATE TABLE employers (id INTEGER NOT NU
 ActiveRecord::Base.connection.execute 'CREATE TABLE employees (id INTEGER NOT NULL PRIMARY KEY, deleted_at DATETIME)'
 ActiveRecord::Base.connection.execute 'CREATE TABLE jobs (id INTEGER NOT NULL PRIMARY KEY, employer_id INTEGER NOT NULL, employee_id INTEGER NOT NULL, deleted_at DATETIME)'
 ActiveRecord::Base.connection.execute 'CREATE TABLE custom_column_models (id INTEGER NOT NULL PRIMARY KEY, destroyed_at DATETIME)'
+ActiveRecord::Base.connection.execute 'CREATE TABLE non_paranoid_models (id INTEGER NOT NULL PRIMARY KEY, parent_model_id INTEGER)'
 
 class ParanoiaTest < Test::Unit::TestCase
   def test_plain_model_class_is_not_paranoid
@@ -305,6 +306,34 @@ class ParanoiaTest < Test::Unit::TestCase
     refute c.destroyed?
   end
 
+  def test_restore_with_associations
+    parent = ParentModel.create
+    first_child = parent.very_related_models.create
+    second_child = parent.non_paranoid_models.create
+
+    parent.destroy
+    assert_equal false, parent.deleted_at.nil?
+    assert_equal false, first_child.reload.deleted_at.nil?
+    assert_equal true, second_child.destroyed?
+
+    parent.restore!
+    assert_equal true, parent.deleted_at.nil?
+    assert_equal false, first_child.reload.deleted_at.nil?
+    assert_equal true, second_child.destroyed?
+
+    parent.destroy
+    parent.restore(:recursive => true)
+    assert_equal true, parent.deleted_at.nil?
+    assert_equal true, first_child.reload.deleted_at.nil?
+    assert_equal true, second_child.destroyed?
+
+    parent.destroy
+    ParentModel.restore(parent.id, :recursive => true)
+    assert_equal true, parent.reload.deleted_at.nil?
+    assert_equal true, first_child.reload.deleted_at.nil?
+    assert_equal true, second_child.destroyed?
+  end
+
   def test_observers_notified
     a = ParanoidModelWithObservers.create
     a.destroy
@@ -366,6 +395,8 @@ end
 class ParentModel < ActiveRecord::Base
   acts_as_paranoid
   has_many :related_models
+  has_many :very_related_models, :class_name => 'RelatedModel', dependent: :destroy
+  has_many :non_paranoid_models, dependent: :destroy
 end
 
 class RelatedModel < ActiveRecord::Base
@@ -395,6 +426,9 @@ class CustomColumnModel < ActiveRecord::Base
   acts_as_paranoid column: :destroyed_at
 end
 
+class NonParanoidModel < ActiveRecord::Base
+end
+
 class ParanoidModelWithObservers < ParanoidModel
   def observers_notified
     @observers_notified ||= []