https://api.drupal.org/api/drupal/core%21modules%21user%21tests%21src%21Functional%21UserRegistrationTest.php/10
UserRegistrationTest.php | Drupal API
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https://api.drupal.org/api/drupal/core%21modules%21user%21tests%21src%21Functional%21UserRegistrationTest.php/function/UserRegistrationTest%3A%3AtestRegistrationDefaultValues/11.x
function UserRegistrationTest::testRegistrationDefaultValues | Drupal API
functiondrupalapi