class NullCoalesce

Provides a Null Coalesce process plugin.

Given a set of values provided to the plugin, the plugin will return the first non-null value.

Available configuration keys:

  • source: The input array.
  • default_value: (optional) The value to return if all values are NULL. if not provided, NULL is returned if all values are NULL.

Example: Given source keys of foo, bar, and baz:


process_key:
  plugin: null_coalesce
  source:
    - foo
    - bar
    - baz

This plugin will return the equivalent of `foo ?? bar ?? baz`

Attributes

#[MigrateProcess('null_coalesce')]

Hierarchy

  • class \Drupal\migrate\Plugin\migrate\process\NullCoalesce implements \Drupal\migrate\ProcessPluginBase

Expanded class hierarchy of NullCoalesce

1 file declares its use of NullCoalesce
NullCoalesceTest.php in core/modules/migrate/tests/src/Unit/process/NullCoalesceTest.php

File

core/modules/migrate/src/Plugin/migrate/process/NullCoalesce.php, line 34

Namespace

Drupal\migrate\Plugin\migrate\process
View source
class NullCoalesce extends ProcessPluginBase {
  
  /**
   * {@inheritdoc}
   */
  public function transform($value, MigrateExecutableInterface $migrate_executable, Row $row, $destination_property) {
    if (!is_array($value)) {
      throw new MigrateException("The input value should be an array.");
    }
    foreach ($value as $val) {
      if (NULL !== $val) {
        return $val;
      }
    }
    if (isset($this->configuration['default_value'])) {
      return $this->configuration['default_value'];
    }
    return NULL;
  }

}

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