symfony/finder · error · InvalidArgumentException

The SortableIterator takes a PHP callable or a valid…

Error message

The SortableIterator takes a PHP callable or a valid built-in sort algorithm as an argument.

What it means

SortableIterator accepts either a built-in sort constant (SORT_BY_NAME, SORT_BY_TYPE, SORT_BY_ACCESSED_TIME, SORT_BY_CHANGED_TIME, SORT_BY_MODIFIED_TIME, SORT_BY_NONE, and their _AS_STRING variants) or a PHP callable comparator; anything else throws InvalidArgumentException with this message.

Solutions

1. Use class constants: SortableIterator::SORT_BY_NAME, or a closure fn (\SplFileInfo $a, \SplFileInfo $b) => ...
2. Replace string sort names with the corresponding constant or callable
3. Verify the sort int is one of the class's SORT_BY_* constants after a library upgrade

Example fix

// before
$finder->sort('name'); // string is neither callable nor a valid algorithm
// after
$finder->sort(\Symfony\Component\Finder\Iterator\SortableIterator::SORT_BY_NAME);

$valid = [SortableIterator::SORT_BY_NONE, SortableIterator::SORT_BY_NAME, SortableIterator::SORT_BY_TYPE, SortableIterator::SORT_BY_ACCESSED_TIME, SortableIterator::SORT_BY_CHANGED_TIME, SortableIterator::SORT_BY_MODIFIED_TIME]; if (!is_callable($sort) && !in_array($sort, $valid, true)) { throw new \InvalidArgumentException('Invalid sort'); }

function isValidSort(mixed $sort): bool { return is_callable($sort) || in_array($sort, [SortableIterator::SORT_BY_NONE, SortableIterator::SORT_BY_NAME, SortableIterator::SORT_BY_TYPE, SortableIterator::SORT_BY_ACCESSED_TIME, SortableIterator::SORT_BY_CHANGED_TIME, SortableIterator::SORT_BY_MODIFIED_TIME], true); }

try { $finder->sort($sort); } catch (\InvalidArgumentException $e) { /* handle invalid sort */ }

When it happens

Trigger: new SortableIterator($iterator, 'name') (string not a callable/constant), Finder::sort('bogus'), passing an int outside the defined constant range, or a non-callable value like an array of sort options.

Common situations: Passing 'name' as a string expecting it to map to SORT_BY_NAME, using removed/renamed constants after upgrading, config-driven sort values read as raw strings.

Understand the failure class

Background: "Must be a positive integer", "Invalid value", "Unsupported": the invalid-argument-value error family, when a library rejects the value you pass — this error's family across 35 libraries.

Related errors

• Invalid operator " ".
• Invalid PHP callback.
• Don't understand " " as a date test.
• Don't understand " " as a number test.
• Invalid number " ".

AI-assisted analysis of symfony/finder@4d6c057bfd (2026-09-13). Data as JSON: /api/errors/fdf9cf5420e76758. Report an issue: GitHub.

Appendix: source

Thrown at Iterator/SortableIterator.php:83

                return $order * strcmp($a->getRealPath() ?: $a->getPathname(), $b->getRealPath() ?: $b->getPathname());
            };
        } elseif (self::SORT_BY_ACCESSED_TIME === $sort) {
            $this->sort = static fn (\SplFileInfo $a, \SplFileInfo $b) => $order * ($a->getATime() - $b->getATime());
        } elseif (self::SORT_BY_CHANGED_TIME === $sort) {
            $this->sort = static fn (\SplFileInfo $a, \SplFileInfo $b) => $order * ($a->getCTime() - $b->getCTime());
        } elseif (self::SORT_BY_MODIFIED_TIME === $sort) {
            $this->sort = static fn (\SplFileInfo $a, \SplFileInfo $b) => $order * ($a->getMTime() - $b->getMTime());
        } elseif (self::SORT_BY_EXTENSION === $sort) {
            $this->sort = static fn (\SplFileInfo $a, \SplFileInfo $b) => $order * strnatcmp($a->getExtension(), $b->getExtension());
        } elseif (self::SORT_BY_SIZE === $sort) {
            $this->sort = static fn (\SplFileInfo $a, \SplFileInfo $b) => $order * ($a->getSize() - $b->getSize());
        } elseif (self::SORT_BY_NONE === $sort) {
            $this->sort = $order;
        } elseif (\is_callable($sort)) {
            $this->sort = $reverseOrder ? static fn (\SplFileInfo $a, \SplFileInfo $b) => -$sort($a, $b) : $sort(...);
        } else {
            throw new \InvalidArgumentException('The SortableIterator takes a PHP callable or a valid built-in sort algorithm as an argument.');
        }
    }

    public function getIterator(): \Traversable
    {
        if (1 === $this->sort) {
            yield from $this->iterator;

            return;
        }

        $keys = $values = [];
        foreach ($this->iterator as $key => $value) {
            $keys[] = $key;
            $values[] = $value;
        }

        if (-1 === $this->sort) {

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