Reset user password without using "Forgot password?"

Question

I know that in Drupal 7 I could reset the user #1 password via code.

define('DRUPAL_ROOT', getcwd());
require_once DRUPAL_ROOT . '/includes/bootstrap.inc';
drupal_bootstrap(DRUPAL_BOOTSTRAP_FULL);
require_once DRUPAL_ROOT . '/includes/password.inc';
$newhash = user_hash_password('newpass');
$updatepass = db_update('users') 
  ->fields(array('pass' => $newhash))
  ->condition('uid', '1', '=')
  ->execute();

(user_hash_password() doesn't exist anymore in Drupal 8.)

Alternatively, I could use the following code.

define('DRUPAL_ROOT', getcwd());
require_once DRUPAL_ROOT . '/includes/bootstrap.inc';
drupal_bootstrap(DRUPAL_BOOTSTRAP_FULL);
require_once DRUPAL_ROOT . '/includes/password.inc';
$edit['pass'] = 'newpass';
$account= user_load(1);
user_save($account, $edit);

What is the equivalent code for Drupal 8? What API should I use for this purpose?

Answer 1

It's easier these days:

$account = \Drupal::entityTypeManager()->getStorage('user')->load(1);
$account->setPassword('new password');
$account->save();

Answer 2

Alternately, since you seem to be running this as a standalone script, there is a Drush (9.x) command

drush user:password admin mynewpassword

For Drush 8.x and earlier::

drush user-password admin --password=newpass