isStringNotEmpty example

/** @var string $file */
        $file = $this->file;

        return new LazyOpenStream($file, 'r+');
    }

    public function moveTo($targetPath): void
    {
        $this->validateActive();

        if (false === $this->isStringNotEmpty($targetPath)) {
            throw new InvalidArgumentException(
                'Invalid path provided for move operation; must be a non-empty string'
            );
        }

        if ($this->file) {
            $this->moved = PHP_SAPI === 'cli'
                ? rename($this->file, $targetPath)
                : move_uploaded_file($this->file, $targetPath);
        } else {
            Utils::copyToStream(