silverstripe-frameworktest/code/FrameworkTestRole.php

<?php

use SilverStripe\ORM\DataObject;
use SilverStripe\ORM\DB;
use SilverStripe\Core\Extension;
use SilverStripe\Security\Member;
use SilverStripe\Forms\FieldList;
use SilverStripe\Forms\TreeDropdownField;

class FrameworkTestRole extends Extension
{

    private static $has_one = array(
        'FavouritePage' => 'SilverStripe\\CMS\\Model\\SiteTree',
    );

    protected function updateCMSFields(FieldList $fields)
    {
        $fields->addFieldToTab(
            'Root.Main',
            new TreeDropdownField("FavouritePageID", "Favourite page", "SilverStripe\\CMS\\Model\\SiteTree")
        );
    }

    protected function onRequireDefaultRecords()
    {
        $hasTestMembers = Member::get()->find('Email', 'hayley@test.com');
        if (!$hasTestMembers) {
            foreach ($this->data() as $name) {
                $member = new Member(array(
                    'FirstName' => $name,
                    'FirstName' => 'Smith',
                    'Email' => "{$name}@test.com",
                ));
                $member->write();
            }

            DB::alteration_message("Added default records to Member table", "created");
        }
    }

    /**
     * Contains test data
     *
     * @return array
     */
    public function data()
    {
        return array(
            'Hayley', 'Octavius', 'Walker', 'Gary', 'Elton', 'Janna', 'Ursa', 'Lars', 'Moses', 'Lareina', 'Elmo', 'Shea', 'Duncan', 'Velma', 'Acton', 'Galena', 'Heidi', 'Troy', 'Elliott', 'Whitney', 'Summer', 'Olga', 'Tatum', 'Zeph', 'Jared', 'Hilda', 'Quinlan', 'Chaim', 'Xenos', 'Cara', 'Tatiana', 'Tyrone', 'Juliet', 'Chester', 'Hannah', 'Imani', 'Quinn', 'Ariel', 'Aretha', 'Courtney ', 'Shellie', 'Garrett', 'Camilla', 'Simon', 'Mohammad', 'Kirby', 'Rae', 'Xena', 'Noel', 'Omar', 'Shannon', 'Iola', 'Maia', 'Serina', 'Taylor', 'Alice', 'Lucy', 'Austin', 'Abel', 'Yetta', 'Ulysses', 'Donovan', 'Castor', 'Emmanuel', 'Nero', 'Virginia', 'Gregory', 'Neville', 'Len', 'Knox', 'Gavin', 'Pascale', 'Hyatt', 'Alden', 'Emerald', 'Cherokee', 'Adam', 'Uma', 'Serena', 'Isabelle', 'Kieran', 'Gay', 'Lavinia', 'Elvis', 'Illana', 'Lee', 'Ariana', 'Hilel', 'Gage', 'Larissa', 'Richard', 'Allen'
        );
    }
}