require "cases/helper" require "support/connection_helper" module ActiveRecord class Mysql2TransactionTest < ActiveRecord::Mysql2TestCase self.use_transactional_tests = false class Sample < ActiveRecord::Base self.table_name = "samples" end setup do @connection = ActiveRecord::Base.connection @connection.clear_cache! @connection.transaction do @connection.drop_table "samples", if_exists: true @connection.create_table("samples") do |t| t.integer "value" end end Sample.reset_column_information end teardown do @connection.drop_table "samples", if_exists: true end test "raises Deadlocked when a deadlock is encountered" do assert_raises(ActiveRecord::Deadlocked) do s1 = Sample.create value: 1 s2 = Sample.create value: 2 thread = Thread.new do Sample.transaction do s1.lock! sleep 1 s2.update_attributes value: 1 end end sleep 0.5 Sample.transaction do s2.lock! sleep 1 s1.update_attributes value: 2 end thread.join end end end end