code: protected function applyFix(\SplFileInfo $file, Tokens $tokens)
      {
          foreach ($tokens as $index => $token) {
              if (!$token->equalsAny(['[', [CT::T_ARRAY_INDEX_CURLY_BRACE_OPEN]])) {
                  continue;
              }
  
              if (\in_array('inside', $this->configuration['positions'], true)) {
                  if ($token->equals('[')) {
                      $endIndex = $tokens->findBlockEnd(Tokens::BLOCK_TYPE_INDEX_SQUARE_BRACE, $index);
                  } else {
                      $endIndex = $tokens->findBlockEnd(Tokens::BLOCK_TYPE_ARRAY_INDEX_CURLY_BRACE, $index);
                  }
  
                  // remove space after opening `[` or `{`
                  if ($tokens[$index + 1]->isWhitespace(" \t")) {
                      $tokens->clearAt($index + 1);
                  }
  
                  // remove space before closing `]` or `}`
                  if ($tokens[$endIndex - 1]->isWhitespace(" \t")) {
                      $tokens->clearAt($endIndex - 1);
                  }
              }
  
              if (\in_array('outside', $this->configuration['positions'], true)) {
                  $prevNonWhitespaceIndex = $tokens->getPrevNonWhitespace($index);
                  if ($tokens[$prevNonWhitespaceIndex]->isComment()) {
                      continue;
                  }
  
                  $tokens->removeLeadingWhitespace($index);
              }
          }
      }
docs: {@inheritdoc}