require "cases/helper"
require 'support/connection_helper'

module ActiveRecord
  class PostgresqlTransactionTest < ActiveRecord::PostgreSQLTestCase
    self.use_transactional_tests = false

    class Sample < ActiveRecord::Base
      self.table_name = 'samples'
    end

    setup do
      @connection = ActiveRecord::Base.connection

      @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 SerializationFailure when a serialization failure occurs" do
      with_warning_suppression do
        assert_raises(ActiveRecord::SerializationFailure) do
          thread = Thread.new do
            Sample.transaction isolation: :serializable do
              Sample.delete_all

              10.times do |i|
                sleep 0.1

                Sample.create value: i
              end
            end
          end

          sleep 0.1

          Sample.transaction isolation: :serializable do
            Sample.delete_all

            10.times do |i|
              sleep 0.1

              Sample.create value: i
            end
          end

          thread.join
        end
      end
    end

    test "raises DeadlockDetected when a deadlock is encountered" do
      with_warning_suppression do
        assert_raises(ActiveRecord::DeadlockDetected) 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

    protected

    def with_warning_suppression
      log_level = @connection.client_min_messages
      @connection.client_min_messages = 'error'
      yield
      @connection.client_min_messages = log_level
    end
  end
end