Issue #2882276 by benjifisher, estoyausente, nuez, kristiaanvandeneynde,...

namespace Drupal\migrate\Plugin\migrate\process;

use Drupal\migrate\MigrateException;

use Drupal\migrate\MigrateExecutableInterface;

use Drupal\migrate\ProcessPluginBase;

use Drupal\migrate\Row;

 * Passes the source value to a callback.

 *

 * The callback process plugin allows simple processing of the value, such as

 * strtolower(). The callable takes the source value as the single mandatory

 * argument. No additional arguments can be passed to the callback.

 * strtolower(). To pass more than one argument, pass an array as the source

 * and set the unpack_source option.

 *

 * Available configuration keys:

 * - callable: The name of the callable method.

 * - unpack_source: (optional) Whether to interpret the source as an array of

 *   arguments.

 *

 * Examples:

 *

 *     source: source_field

 * @endcode

 *

 * An example where the callback accepts more than one argument:

 *

 * @code

 * source:

 *   plugin: source_plugin_goes_here

 *   constants:

 *     slash: /

 * process:

 *   field_link_url:

 *     plugin: callback

 *     callable: rtrim

 *     unpack_source: true

 *     source:

 *       - url

 *       - constants/slash

 * @endcode

 *

 * This will remove the trailing '/', if any, from a URL.

 *

 * @see \Drupal\migrate\Plugin\MigrateProcessInterface

 *

 * @MigrateProcessPlugin(

   * {@inheritdoc}

   */

  public function transform($value, MigrateExecutableInterface $migrate_executable, Row $row, $destination_property) {

    if (!empty($this->configuration['unpack_source'])) {

      if (!is_array($value)) {

        throw new MigrateException(sprintf("When 'unpack_source' is set, the source must be an array. Instead it was of type '%s'", gettype($value)));

      }

      return call_user_func($this->configuration['callable'], ...$value);

    }

    return call_user_func($this->configuration['callable'], $value);

  }

namespace Drupal\Tests\migrate\Unit\process;

use Drupal\migrate\MigrateException;

use Drupal\migrate\Plugin\migrate\process\Callback;

/**

    ];

  }

  /**

   * Test callback with valid "callable" and multiple arguments.

   *

   * @dataProvider providerCallbackArray

   */

  public function testCallbackArray($callable, $args, $result) {

    $configuration = ['callable' => $callable, 'unpack_source' => TRUE];

    $this->plugin = new Callback($configuration, 'map', []);

    $value = $this->plugin->transform($args, $this->migrateExecutable, $this->row, 'destination_property');

    $this->assertSame($result, $value);

  }

  /**

   * Data provider for ::testCallbackArray().

   */

  public function providerCallbackArray() {

    return [

      'date format' => [

        'date',

        ['Y-m-d', 995328000],

        '2001-07-17',

      ],

      'rtrim' => [

        'rtrim',

        ['https://www.example.com/', '/'],

        'https://www.example.com',

      ],

      'str_replace' => [

        'str_replace',

        [['One', 'two'], ['1', '2'], 'One, two, three!'],

        '1, 2, three!',

      ],

    ];

  }

  /**

   * Test callback exceptions.

   *

   * @param string $message

   *   The expected exception message.

   * @param array $configuration

   *   The plugin configuration being tested.

   * @param string $class

   *   (optional) The expected exception class.

   * @param mixed $args

   *   (optional) Arguments to pass to the transform() method.

   *

   * @dataProvider providerCallbackExceptions

   */

  public function testCallbackExceptions($message, $configuration) {

    $this->expectException(\InvalidArgumentException::class);

  public function testCallbackExceptions($message, array $configuration, $class = 'InvalidArgumentException', $args = NULL) {

    $this->expectException($class);

    $this->expectExceptionMessage($message);

    $this->plugin = new Callback($configuration, 'map', []);

    $this->plugin->transform($args, $this->migrateExecutable, $this->row, 'destination_property');

  }

  /**

        'message' => 'The "callable" must be a valid function or method.',

        'configuration' => ['callable' => 'nonexistent_callable'],

      ],

      'array required' => [

        'message' => "When 'unpack_source' is set, the source must be an array. Instead it was of type 'string'",

        'configuration' => ['callable' => 'count', 'unpack_source' => TRUE],

        'class' => MigrateException::class,

        'args' => 'This string is not an array.',

      ],

    ];

  }