Fatal error: Uncaught Error: Class "Drupal\Tests\migrate\Unit\process\MigrateProcessTestCase" not found in /home/www/drupal8/test/modules/migrate_plus/tests/src/Unit/process/ArrayPopTest.php:15
Stack trace:
#0 {main}
thrown in /home/www/drupal8/test/modules/migrate_plus/tests/src/Unit/process/ArrayPopTest.php on line 15