/**
* Sync a user with new repositories.
*
* @param \App\Models\User\User $user
* @param \Illuminate\Support\Collection $repositories
*
* @return void
*/
public function sync(User $user, Collection $repositories)
{
$existing = $user->repositories;
$repositories = $this->map($repositories);
$repositories = $this->create($repositories, $existing);
$user->repositories()->saveMany($repositories);
}