module TemporalTables
  # This is required for eager_load to work in Rails 6.0
  module ArelTable
    def create_join(to, constraint = nil, klass = Arel::Nodes::InnerJoin)
      join = super
      if at_value = Thread.current[:at_time]
        join = join.
          and(to[:eff_to].gteq(at_value)).
          and(to[:eff_from].lteq(at_value))
      end
      join
    end
  end
end

case Rails::VERSION::MAJOR
when 6
  Arel::Table.prepend TemporalTables::ArelTable
end