/**
  * Run the outstanding migrations for a given bundle.
  *
  * @param  string  $bundle
  * @param  int     $version
  * @return void
  */
 public function migrate($bundle = null, $version = null)
 {
     $migrations = $this->resolver->outstanding($bundle);
     if (count($migrations) == 0) {
         echo "No outstanding migrations.";
         return;
     }
     // We need to grab the latest batch ID and increment it by one.
     // This allows us to group the migrations so we can easily
     // determine which migrations need to roll back.
     $batch = $this->database->batch() + 1;
     foreach ($migrations as $migration) {
         $migration['migration']->up();
         echo 'Migrated: ' . $this->display($migration) . PHP_EOL;
         // After running a migration, we log its execution in the migration
         // table so that we can easily determine which migrations we'll
         // reverse in the event of a migration rollback.
         $this->database->log($migration['bundle'], $migration['name'], $batch);
     }
 }