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function text_summary in Drupal 8

Same name and namespace in other branches
  1. 7 modules/field/modules/text/text.module \text_summary()
  2. 9 core/modules/text/text.module \text_summary()
  3. 10 core/modules/text/text.module \text_summary()

Generates a trimmed, formatted version of a text field value.

If the end of the summary is not indicated using the <!--break--> delimiter then we generate the summary automatically, trying to end it at a sensible place such as the end of a paragraph, a line break, or the end of a sentence (in that order of preference).

Parameters

$text: The content for which a summary will be generated.

$format: The format of the content. If the line break filter is present then we treat newlines embedded in $text as line breaks. If the htmlcorrector filter is present, it will be run on the generated summary (if different from the incoming $text).

$size: The desired character length of the summary. If omitted, the default value will be used. Ignored if the special delimiter is present in $text.

Return value

The generated summary.

3 calls to text_summary()
node_tokens in core/modules/node/node.tokens.inc
Implements hook_tokens().
TextSummaryTest::assertTextSummary in core/modules/text/tests/src/Kernel/TextSummaryTest.php
Calls text_summary() and asserts that the expected teaser is returned.
TextTrimmedFormatter::preRenderSummary in core/modules/text/src/Plugin/Field/FieldFormatter/TextTrimmedFormatter.php
Pre-render callback: Renders a processed text element's #markup as a summary.

File

core/modules/text/text.module, line 64
Defines simple text field types.

Code

function text_summary($text, $format = NULL, $size = NULL) {
  if (!isset($size)) {
    $size = \Drupal::config('text.settings')
      ->get('default_summary_length');
  }

  // Find where the delimiter is in the body
  $delimiter = strpos($text, '<!--break-->');

  // If the size is zero, and there is no delimiter, the entire body is the summary.
  if ($size == 0 && $delimiter === FALSE) {
    return $text;
  }

  // If a valid delimiter has been specified, use it to chop off the summary.
  if ($delimiter !== FALSE) {
    return substr($text, 0, $delimiter);
  }

  // Retrieve the filters of the specified text format, if any.
  if (isset($format)) {
    $filter_format = FilterFormat::load($format);

    // If the specified format does not exist, return nothing. $text is already
    // filtered text, but the remainder of this function will not be able to
    // ensure a sane and secure summary.
    if (!$filter_format || !($filters = $filter_format
      ->filters())) {
      return '';
    }
  }

  // If we have a short body, the entire body is the summary.
  if (mb_strlen($text) <= $size) {
    return $text;
  }

  // If the delimiter has not been specified, try to split at paragraph or
  // sentence boundaries.
  // The summary may not be longer than maximum length specified. Initial slice.
  $summary = Unicode::truncate($text, $size);

  // Store the actual length of the UTF8 string -- which might not be the same
  // as $size.
  $max_rpos = strlen($summary);

  // How much to cut off the end of the summary so that it doesn't end in the
  // middle of a paragraph, sentence, or word.
  // Initialize it to maximum in order to find the minimum.
  $min_rpos = $max_rpos;

  // Store the reverse of the summary. We use strpos on the reversed needle and
  // haystack for speed and convenience.
  $reversed = strrev($summary);

  // Build an array of arrays of break points grouped by preference.
  $break_points = [];

  // A paragraph near the end of sliced summary is most preferable.
  $break_points[] = [
    '</p>' => 0,
  ];

  // If no complete paragraph then treat line breaks as paragraphs.
  $line_breaks = [
    '<br />' => 6,
    '<br>' => 4,
  ];

  // Newline only indicates a line break if line break converter
  // filter is present.
  if (isset($format) && $filters
    ->has('filter_autop') && $filters
    ->get('filter_autop')->status) {
    $line_breaks["\n"] = 1;
  }
  $break_points[] = $line_breaks;

  // If the first paragraph is too long, split at the end of a sentence.
  $break_points[] = [
    '. ' => 1,
    '! ' => 1,
    '? ' => 1,
    '。' => 0,
    '؟ ' => 1,
  ];

  // Iterate over the groups of break points until a break point is found.
  foreach ($break_points as $points) {

    // Look for each break point, starting at the end of the summary.
    foreach ($points as $point => $offset) {

      // The summary is already reversed, but the break point isn't.
      $rpos = strpos($reversed, strrev($point));
      if ($rpos !== FALSE) {
        $min_rpos = min($rpos + $offset, $min_rpos);
      }
    }

    // If a break point was found in this group, slice and stop searching.
    if ($min_rpos !== $max_rpos) {

      // Don't slice with length 0. Length must be <0 to slice from RHS.
      $summary = $min_rpos === 0 ? $summary : substr($summary, 0, 0 - $min_rpos);
      break;
    }
  }

  // If the htmlcorrector filter is present, apply it to the generated summary.
  if (isset($format) && $filters
    ->has('filter_htmlcorrector') && $filters
    ->get('filter_htmlcorrector')->status) {
    $summary = Html::normalize($summary);
  }
  return $summary;
}