Eris\Generator\SubsetGenerator::shrink PHP Метод

    public function shrink(GeneratedValue $set)
    {
        // TODO: see SetGenerator::shrink()
        if (!$this->contains($set)) {
            throw new DomainException('Cannot shrink {' . var_export($set, true) . '} because ' . 'it does not belong to the domain of this set');
        }
        if (count($set->unbox()) === 0) {
            return $set;
        }
        $input = $set->input();
        // TODO: make deterministic by returning an array of GeneratedValues
        $indexOfElementToRemove = array_rand($input);
        unset($input[$indexOfElementToRemove]);
        return GeneratedValue::fromJustValue(array_values($input), 'subset');
    }