class RSpec::Matchers::BuiltIn::ThrowSymbol

def throw_description(symbol, arg)
  symbol_description = symbol.is_a?(String) ? symbol : symbol.inspect
  arg_description = if arg
                      " with #{arg.inspect}"
                    elsif @expected_arg && @caught_symbol == @expected_symbol
                      " with no argument"
                    else
                      ""
                    end
  symbol_description + arg_description
end