src/Client.php
public function authenticate($authMethod, $options)
    {
        $sm = $this->getServiceManager();
        $authListener = $sm->get($authMethod);
        $authListener->setOptions($options);

        $this->getHttpClient()->getEventManager()->attachAggregate($authListener);
    }
public function authenticate($authMethod, $options)
    {
        $sm = $this->getServiceManager();
        $authListener = $sm->get($authMethod);
        $authListener->setOptions($options);

        $this->getHttpClient()->getEventManager()->attachAggregate($authListener);
    }
Authenticate a user for all next requests

@param string      $tokenOrLogin  GitHub private token/username/client ID
@param null|string $password      GitHub password/secret
@param string $authMethod