6 methods override ArgumentValidatorPluginBase::validate_argument() in Views (for Drupal 7) 8.3

Node::validate_argument in lib/Views/node/Plugin/views/argument_validator/Node.php

None::validate_argument in lib/Drupal/views/Plugin/views/argument_validator/None.php

Numeric::validate_argument in lib/Drupal/views/Plugin/views/argument_validator/Numeric.php

Php::validate_argument in lib/Drupal/views/Plugin/views/argument_validator/Php.php

Term::validate_argument in lib/Views/taxonomy/Plugin/views/argument_validator/Term.php

User::validate_argument in lib/Views/user/Plugin/views/argument_validator/User.php