public static function Percentage::format in Drupal 8

Same name and namespace in other branches

1. 9 core/lib/Drupal/Core/Batch/Percentage.php \Drupal\Core\Batch\Percentage::format()
2. 10 core/lib/Drupal/Core/Batch/Percentage.php \Drupal\Core\Batch\Percentage::format()

Formats the percent completion for a batch set.

Parameters

int $total: The total number of operations.

int $current: The number of the current operation. This may be a floating point number rather than an integer in the case of a multi-step operation that is not yet complete; in that case, the fractional part of $current represents the fraction of the operation that has been completed.

Return value

string The properly formatted percentage, as a string. We output percentages using the correct number of decimal places so that we never print "100%" until we are finished, but we also never print more decimal places than are meaningful.

See also

_batch_process()

2 calls to Percentage::format()

PercentagesTest::testPercentages in core/tests/Drupal/Tests/Core/Batch/PercentagesTest.php

@dataProvider providerTestPercentages @covers ::format

_batch_api_percentage in core/includes/batch.inc

Formats the percent completion for a batch set.

File

core/lib/Drupal/Core/Batch/Percentage.php, line 29

Class

Percentage

Helper methods for the batch system.

Namespace

Drupal\Core\Batch

Code

public static function format($total, $current) {
  if (!$total || $total == $current) {

    // If $total doesn't evaluate as true or is equal to the current set, then
    // we're finished, and we can return "100".
    $percentage = '100';
  }
  else {

    // We add a new digit at 200, 2000, etc. (since, for example, 199/200
    // would round up to 100% if we didn't).
    $decimal_places = max(0, floor(log10($total / 2.0)) - 1);
    do {

      // Calculate the percentage to the specified number of decimal places.
      $percentage = sprintf('%01.' . $decimal_places . 'f', round($current / $total * 100, $decimal_places));

      // When $current is an integer, the above calculation will always be
      // correct. However, if $current is a floating point number (in the case
      // of a multi-step batch operation that is not yet complete), $percentage
      // may be erroneously rounded up to 100%. To prevent that, we add one
      // more decimal place and try again.
      $decimal_places++;
    } while ($percentage == '100');
  }
  return $percentage;
}