code: protected function applyFix(\SplFileInfo $file, Tokens $tokens)
      {
          $lastIndex = $tokens->count() - 1;
          for ($index = $lastIndex; $index >= 0; --$index) {
              if (!$tokens[$index]->isGivenKind(T_FUNCTION)) {
                  continue;
              }
  
              // Return types are only available since PHP 7.0
              $this->fixFunctionReturnType($tokens, $index);
              $this->fixFunctionArguments($tokens, $index);
          }
      }
docs: {@inheritdoc}