briannesbitt/Carbon · error · Carbon\Exceptions\InvalidIntervalException

Rounding is only possible with single unit intervals.

Error message

Rounding is only possible with single unit intervals.

What it means

Error "Rounding is only possible with single unit intervals." thrown in briannesbitt/Carbon.

Source

Thrown at src/Carbon/Traits/IntervalRounding.php:50

        if (\in_array($action, ['round', 'floor', 'ceil'])) {
            return $this->{$action.'Unit'}(substr($method, \strlen($action)), ...$parameters);
        }

        return null;
    }

    protected function roundWith(DateInterval|string|float|int $precision, callable|string $function): ?static
    {
        $unit = 'second';

        if ($precision instanceof DateInterval) {
            $precision = CarbonInterval::instance($precision)->forHumans(['locale' => 'en']);
        }

        if (\is_string($precision) && preg_match('/^\s*(?<precision>\d+)?\s*(?<unit>\w+)(?<other>\W.*)?$/', $precision, $match)) {
            if (trim($match['other'] ?? '') !== '') {
                throw new InvalidIntervalException('Rounding is only possible with single unit intervals.');
            }

            $precision = (int) ($match['precision'] ?: 1);
            $unit = $match['unit'];
        }

        return $this->roundUnit($unit, $precision, $function);
    }
}

View on GitHub (pinned to b13f05955d)

When it happens

Trigger: Thrown at src/Carbon/Traits/IntervalRounding.php:50 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of briannesbitt/Carbon@b13f05955d (2026-08-17). Data as JSON: /api/errors/722b1ac1ef438e9b. Report an issue: GitHub.