Merge pull request #8813 from greyblake/dont_write_timestamps_if_they_are_not_attributes

Write timestamps only if there are timestamps columns

Conflicts:
	activerecord/CHANGELOG.md

activerecord/CHANGELOG.md

+*   Do not try to write timestamps when a table has no timestamps columns.
+
+    Fixes #8813.
+
+    *Sergey Potapov*
+
 *   `index_exists?` with `:name` option does verify specified columns.
 
     Example:

activerecord/lib/active_record/timestamp.rb

@@ -47,7 +47,7 @@ def _create_record
         current_time = current_time_from_proper_timezone
 
         all_timestamp_attributes.each do |column|
-          if respond_to?(column) && respond_to?("#{column}=") && self.send(column).nil?
+          if attributes.key?(column.to_s) && self.send(column).nil?
             write_attribute(column.to_s, current_time)
           end
         end

activerecord/test/cases/timestamp_test.rb

 require 'cases/helper'
+require 'support/ddl_helper'
 require 'models/developer'
 require 'models/owner'
 require 'models/pet'
@@ -424,3 +425,21 @@ def test_all_timestamp_attributes_in_model
     assert_equal [:created_at, :updated_at], toy.send(:all_timestamp_attributes_in_model)
   end
 end
+
+class TimestampsWithoutTransactionTest < ActiveRecord::TestCase
+  include DdlHelper
+  self.use_transactional_fixtures = false
+
+  class TimestampAttributePost < ActiveRecord::Base
+    attr_accessor :created_at, :updated_at
+  end
+
+  def test_do_not_write_timestamps_on_save_if_they_are_not_attributes
+    with_example_table ActiveRecord::Base.connection, "timestamp_attribute_posts", "id integer primary key" do
+      post = TimestampAttributePost.new(id: 1)
+      post.save! # should not try to assign and persist created_at, updated_at
+      assert_nil post.created_at
+      assert_nil post.updated_at
+    end
+  end
+end