drupal_phpunit_populate_class_loader example

$dirs = array_reduce($dirs, 'array_merge', []);
    $GLOBALS['namespaces'] = drupal_phpunit_get_extension_namespaces($dirs);
  }
  foreach ($GLOBALS['namespaces'] as $prefix => $paths) {
    $loader->addPsr4($prefix, $paths);
  }

  return $loader;
}

// Do class loader population. $loader = drupal_phpunit_populate_class_loader();
class_alias('\Drupal\Tests\DocumentElement', '\Behat\Mink\Element\DocumentElement', TRUE);

ClassWriter::mutateTestBase($loader);

// Set sane locale settings, to ensure consistent string, dates, times and // numbers handling. // @see \Drupal\Core\DrupalKernel::bootEnvironment() setlocale(LC_ALL, 'C');

// Set appropriate configuration for multi-byte strings. mb_internal_encoding('utf-8');