Webmozart\Assert\Assert::stringNotEmpty PHP Method

    public static function stringNotEmpty($value, $message = '')
    {
        static::string($value, $message);
        static::notEmpty($value, $message);
    }

 /**
  * {@inheritdoc}
  */
 public static function create($body, TypeResolver $typeResolver = null, DescriptionFactory $descriptionFactory = null, TypeContext $context = null)
 {
     Assert::stringNotEmpty($body);
     Assert::allNotNull([$typeResolver, $descriptionFactory]);
     $parts = preg_split('/(\\s+)/Su', $body, 3, PREG_SPLIT_DELIM_CAPTURE);
     $type = null;
     $variableName = '';
     $isVariadic = false;
     // if the first item that is encountered is not a variable; it is a type
     if (isset($parts[0]) && strlen($parts[0]) > 0 && $parts[0][0] !== '$') {
         $type = $typeResolver->resolve(array_shift($parts), $context);
         array_shift($parts);
     }
     // if the next item starts with a $ or ...$ it must be the variable name
     if (isset($parts[0]) && strlen($parts[0]) > 0 && ($parts[0][0] == '$' || substr($parts[0], 0, 4) === '...$')) {
         $variableName = array_shift($parts);
         array_shift($parts);
         if (substr($variableName, 0, 3) === '...') {
             $isVariadic = true;
             $variableName = substr($variableName, 3);
         }
         if (substr($variableName, 0, 1) === '$') {
             $variableName = substr($variableName, 1);
         }
     }
     $description = $descriptionFactory->create(implode('', $parts), $context);
     return new static($variableName, $type, $isVariadic, $description);
 }