function _filter_autop

Converts line breaks into <p> and <br> in an intelligent fashion.

Based on: http://photomatt.net/scripts/autop

Related topics

File

core/modules/filter/filter.module, line 632

Code

function _filter_autop($text) {
  // All block level tags
  $block = '(?:table|thead|tfoot|caption|col|colgroup|tbody|tr|td|th|div|dl|dd|dt|ul|ol|li|pre|select|option|form|map|area|blockquote|address|math|input|p|h[1-6]|fieldset|legend|hr|article|aside|details|figcaption|figure|footer|header|hgroup|menu|nav|section|summary)';
  // Split at opening and closing PRE, SCRIPT, STYLE, OBJECT, IFRAME tags
  // and comments. We don't apply any processing to the contents of these tags
  // to avoid messing up code. We look for matched pairs and allow basic
  // nesting. For example:
  // "processed<pre>ignored<script>ignored</script>ignored</pre>processed"
  $chunks = preg_split('@(<!--.*?-->|</?(?:pre|script|style|object|iframe|drupal-media|svg|!--)[^>]*>)@i', $text, -1, PREG_SPLIT_DELIM_CAPTURE);
  // Note: PHP ensures the array consists of alternating delimiters and literals
  // and begins and ends with a literal (inserting NULL as required).
  $ignore = FALSE;
  $ignore_tag = '';
  $output = '';
  foreach ($chunks as $i => $chunk) {
    if ($i % 2) {
      if (str_starts_with($chunk, '<!--')) {
        // Nothing to do, this is a comment.
        $output .= $chunk;
        continue;
      }
      // Opening or closing tag?
      $open = $chunk[1] != '/';
      [
        $tag,
      ] = preg_split('/[ >]/', substr($chunk, 2 - $open), 2);
      if (!$ignore) {
        if ($open) {
          $ignore = TRUE;
          $ignore_tag = $tag;
        }
      }
      elseif (!$open && $ignore_tag == $tag) {
        $ignore = FALSE;
        $ignore_tag = '';
      }
    }
    elseif (!$ignore) {
      // Skip if the next chunk starts with Twig theme debug.
      // @see twig_render_template()
      if (isset($chunks[$i + 1]) && $chunks[$i + 1] === '<!-- THEME DEBUG -->') {
        $chunk = rtrim($chunk, "\n");
        $output .= $chunk;
        continue;
      }
      // Skip if the preceding chunk was the end of a Twig theme debug.
      // @see twig_render_template()
      if (isset($chunks[$i - 1])) {
        if (str_starts_with($chunks[$i - 1], '<!-- BEGIN OUTPUT from ') || str_starts_with($chunks[$i - 1], '<!-- 💡 BEGIN CUSTOM TEMPLATE OUTPUT from ')) {
          $chunk = ltrim($chunk, "\n");
          $output .= $chunk;
          continue;
        }
      }
      // Just to make things a little easier, pad the end
      $chunk = preg_replace('|\\n*$|', '', $chunk) . "\n\n";
      $chunk = preg_replace('|<br />\\s*<br />|', "\n\n", $chunk);
      // Space things out a little
      $chunk = preg_replace('!(<' . $block . '[^>]*>)!', "\n\$1", $chunk);
      // Space things out a little
      $chunk = preg_replace('!(</' . $block . '>)!', "\$1\n\n", $chunk);
      // Take care of duplicates
      $chunk = preg_replace("/\n\n+/", "\n\n", $chunk);
      $chunk = preg_replace('/^\\n|\\n\\s*\\n$/', '', $chunk);
      // Make paragraphs, including one at the end
      $chunk = '<p>' . preg_replace('/\\n\\s*\\n\\n?(.)/', "</p>\n<p>\$1", $chunk) . "</p>\n";
      // Problem with nested lists
      $chunk = preg_replace("|<p>(<li.+?)</p>|", "\$1", $chunk);
      $chunk = preg_replace('|<p><blockquote([^>]*)>|i', "<blockquote\$1><p>", $chunk);
      $chunk = str_replace('</blockquote></p>', '</p></blockquote>', $chunk);
      // Under certain strange conditions it could create a P of entirely
      // whitespace
      $chunk = preg_replace('|<p>\\s*</p>\\n?|', '', $chunk);
      $chunk = preg_replace('!<p>\\s*(</?' . $block . '[^>]*>)!', "\$1", $chunk);
      $chunk = preg_replace('!(</?' . $block . '[^>]*>)\\s*</p>!', "\$1", $chunk);
      // Make line breaks
      $chunk = preg_replace('|(?<!<br />)\\s*\\n|', "<br />\n", $chunk);
      $chunk = preg_replace('!(</?' . $block . '[^>]*>)\\s*<br />!', "\$1", $chunk);
      $chunk = preg_replace('!<br />(\\s*</?(?:p|li|div|dl|dd|dt|th|pre|td|ul|ol)>)!', '$1', $chunk);
      $chunk = preg_replace('/&([^#])(?![A-Za-z0-9]{1,8};)/', '&amp;$1', $chunk);
    }
    $output .= $chunk;
  }
  return $output;
}