username_exists filter-hook . WP 4.9.0

Filters whether the given username exists.

Usage

add_filter( 'username_exists', 'filter_function_name_2388', 10, 2 );
function filter_function_name_2388( $user_id, $username ){
	// filter...

	return $user_id;
}

$user_id(int|false)

The user ID associated with the username, or false if the username does not exist.

$username(string)

The username to check for existence.

Changelog

Where the hook is called

return apply_filters( 'username_exists', $user_id, $username );

Where in WP core the hook is used WordPress