module RSpec::Rails::ChannelExampleGroup::ClassMethods

def channel_class
  (_channel_class || described_class).tap do |klass|
    next if klass <= ::ActionCable::Channel::Base
    raise "Described class is not a channel class.\n" \
          "Specify the channel class in the `describe` statement " \
          "or set it manually using `tests MyChannelClass`"
  end
end