saml_sp-8.x-3.x-dev/modules/saml_sp_drupal_login/saml_sp_drupal_login.services.yml

services:
  saml_sp_drupal_login.event_subscriber:
    class: Drupal\saml_sp_drupal_login\EventSubscriber\SamlSpDrupalLoginSubscriber
    arguments: ['@config.factory', '@module_handler', '@current_user', '@messenger']
    tags:
      - { name: event_subscriber }