with([ [1, 'I'], [2, 'II'], [3, 'III'], [4, 'IV'], [5, 'V'], [9, 'IX'], [10, 'X'], [15, 'XV'], [19, 'XIX'], [20, 'XX'], [21, 'XXI'], [40, 'XL'], [50, 'L'], [80, 'LXXX'], [90, 'XC'], [100, 'C'], [110, 'CX'], [400, 'CD'], [500, 'D'], [700, 'DCC'], [900, 'CM'], [1000, 'M'], [1986, 'MCMLXXXVI'], [1990, 'MCMXC'], [2020, 'MMXX'], ]); it('cannot convert negative numbers', function (): void { RomanNumeralsConverter::convert(-1); })->throws(AssertionFailedException::class, 'Cannot convert negative numbers');