code: protected function applyFix(\SplFileInfo $file, Tokens $tokens)
      {
          static $typehintKinds = [
              CT::T_ARRAY_TYPEHINT,
              T_CALLABLE,
              T_NS_SEPARATOR,
              T_STRING,
          ];
  
          for ($index = $tokens->count() - 1; $index >= 0; --$index) {
              if (!$tokens[$index]->isGivenKind(CT::T_NULLABLE_TYPE)) {
                  continue;
              }
  
              // remove whitespaces only if there are only whitespaces
              // between '?' and the variable type
              if (
                  $tokens[$index + 1]->isWhitespace() &&
                  $tokens[$index + 2]->isGivenKind($typehintKinds)
              ) {
                  $tokens->removeTrailingWhitespace($index);
              }
          }
      }
docs: {@inheritdoc}