original_string: protected function normalize(array $input) : array
      {
          $normalized = [];
          foreach ($this->rules() as $field => $value) {
              $normalized[$field] = $input[$field] ?? '';
          }
          return $normalized;
      }
code: protected function normalize(array $input) : array
      {
          $normalized = [];
          foreach ($this->rules() as $field => $value) {
              $normalized[$field] = $input[$field] ?? '';
          }
          return $normalized;
      }
code_tokens: protected function normalize ( array $ input ) : array { $ normalized = [ ] ; foreach ( $ this -> rules ( ) as $ field => $ value ) { $ normalized [ $ field ] = $ input [ $ field ] ?? '' ; } return $ normalized ; }
docstring: Remove unexpected fields and ensure all fields in rules array are present
  @param $input
  @return array
docstring_tokens: Remove unexpected fields and ensure all fields in rules array are present