`@destroyed` should always be set to `false` when an object is duped.

activerecord/CHANGELOG.md

+*   `@destroyed` should always be set to `false` when an object is duped.
+
+    *Kuldeep Aggarwal*
+
 *   Fixed has_many association to make it support irregular inflections.
 
     Fixes #8928.

activerecord/lib/active_record/core.rb

@@ -267,6 +267,7 @@ def initialize_dup(other) # :nodoc:
       @attributes_cache  = {}
 
       @new_record  = true
+      @destroyed   = false
 
       super
     end

activerecord/test/cases/persistence_test.rb

@@ -233,6 +233,22 @@ def test_save_for_record_with_only_primary_key_that_is_provided
     assert_nothing_raised { Minimalistic.create!(:id => 2) }
   end
 
+  def test_save_with_duping_of_destroyed_object
+    developer = Developer.create(name: "Kuldeep")
+    developer.destroy
+    new_developer = developer.dup
+    new_developer.save
+    assert new_developer.persisted?
+  end
+
+  def test_dup_of_destroyed_object_is_not_destroyed
+    developer = Developer.create(name: "Kuldeep")
+    developer.destroy
+    new_developer = developer.dup
+    new_developer.save
+    assert_equal new_developer.destroyed?, false
+  end
+
   def test_create_many
     topics = Topic.create([ { "title" => "first" }, { "title" => "second" }])
     assert_equal 2, topics.size