magento2: TypeError when using PHP 7.2 [Magento 2.3 beta]

Preconditions (*)

1. Magento 2.3 beta (any edition)
2. PHP 7.2.10

Steps to reproduce (*)

1. Create admin user
2. Attempt login with credentials

Expected result (*)

1. Admin user is logged in

Actual result (*)

1. Error is thrown:

TypeError: explode() expects parameter 2 to be string, integer given
#13 <magento_path>/vendor/magento/framework/Encryption/Encryptor.php(266): explode
#12 <magento_path>/vendor/magento/framework/Encryption/Encryptor.php(266): getPasswordVersion

Why this happens

More recent versions of Magento sets the declare(strict_types=1); flag in most (all?) classes. The hash version passed to the explode function is an integer

    const HASH_VERSION_SHA256 = 1;

    const HASH_VERSION_LATEST = 1;

    const PASSWORD_VERSION = 2;

    const DELIMITER = ':';

    private $passwordHashMap = [
        self::PASSWORD_VERSION => self::HASH_VERSION_LATEST
    ];

    private function getPasswordVersion()
    {
        return array_map('intval', explode(self::DELIMITER, $this->passwordHashMap[self::PASSWORD_VERSION]));
    }

Method definition of explode

array explode ( string $delimiter , string $string [, int $limit = PHP_INT_MAX ] )

Notice how the $string parameter requires a string type, but the given value resolves to an integer (1).