class RSpec::Core::Example

def assign_auto_description
  if description.empty? and !pending?
    if RSpec.configuration.expecting_with_rspec?
      metadata[:description] = RSpec::Matchers.generated_description
      RSpec::Matchers.clear_generated_description
    else
      raise NotImplementedError.new(
        "Generated descriptions are only supported when you use rspec-expectations.  " +
        "You must give every example an explicit description."
      )
    end
  end
end